Wharekawa v AEA Constructions Pty Ltd; Building Partners Pty Ltd v AEA Constructions Pty Ltd - [2018] NSWSC 684 - NSWSC 2017 case summary — Zoe

NSWNSWSC

Wharekawa v AEA Constructions Pty Ltd; Building Partners Pty Ltd v AEA Constructions Pty Ltd

[2018] NSWSC 684

Supreme Court of NSW|2017-11-14|Before: Fagan J

View original source

At a glance

Source facts

Court

Supreme Court of NSW

Decision date

2017-11-14

Before

Fagan J

Catchwords

[2009] HCA 48 Angel v Hawkesbury City Council [2008] NSWCA 130
(2008) Aust Torts Reports 81-955 Cox v Fellows [2013] NSWCA 206 Fox v Wood (1981) 148 CLR 438
[1981] HCA 41 Garzo v Liverpool/Campbelltown Christian School [2012] NSWCA 151 Glad Retail Cleaning Pty Ltd v Alvarenga (2013) 86 NSWLR 191
[2013] NSWCA 482 Grills v Leighton Contractors Pty Ltd [2015] NSWCA 72 Kondis v State Transport Authority (1984) 154 CLR 672

Source

Original judgment source is linked above.

Catchwords

[2009] HCA 48 Angel v Hawkesbury City Council [2008] NSWCA 130(2008) Aust Torts Reports 81-955 Cox v Fellows [2013] NSWCA 206 Fox v Wood (1981) 148 CLR 438[1981] HCA 41 Garzo v Liverpool/Campbelltown Christian School [2012] NSWCA 151 Glad Retail Cleaning Pty Ltd v Alvarenga (2013) 86 NSWLR 191[2013] NSWCA 482 Grills v Leighton Contractors Pty Ltd [2015] NSWCA 72 Kondis v State Transport Authority (1984) 154 CLR 672[1984] HCA 61 Kwanchi Pty Ltd v Kocsis (1996) 40 NSWLR 270 Malec v JC Hutton Pty Ltd (1990) 169 CLR 638[1990] HCA 20 Metro North Hospital and Health Service v Pierce [2018] NSWCA 11 Najdovski v Crnojlovic (2008) 72 NSWLR 728[2008] NSWCA 175 Neindorf v Junkovic (2005) 80 ALJR 341[2005] HCA 75 Purkess v Crittenden (1965) 114 CLR 164[1965] HCA 34 Roads and Traffic Authority of NSW v Dederer (2007) 234 CLR 330[1960] HCA 58 Wyong Shire Council v Shirt (1979) 146 CLR 40

Judgment (37 paragraphs)

[1]

[3]

Judgment

On 9 November 2012 the plaintiff, Raymond Wharekawa, was working as a builder's labourer in a terrace house at No 42 Windsor Street, Paddington, when a nail fired from an explosive powered tool on the adjoining property (No 40) struck him in the left temple. He was 28 years of age. The workman who fired the nail gun was Mr Ian Box (since deceased). Mr Box was employed by AEA Constructions Pty Ltd (AEA). The plaintiff claims that his injuries from the accident have prevented him from returning to work as a builder's labourer. He has brought an action against AEA for damages in negligence. AEA denies that it was negligent and disputes the extent of the plaintiff's resulting injuries. It also contends that the plaintiff was contributorily negligent and/or that he was injured solely through the negligent fault of his own employer. As the plaintiff was not engaged by AEA his claim against it is governed by the Civil Liability Act 2002 (NSW), including the regime under that Act for assessment of damages.
At the time of the accident the plaintiff was employed by Building Partners Pty Ltd (the employer). In that employment he was engaged upon an extensive renovation of the terrace house at No 42. Under the Workers Compensation Act 1987 (NSW) the plaintiff has been paid benefits by the employer. The employer has brought a separate proceeding against AEA alleging that the plaintiff's injuries were caused by the negligence of AEA through its employee Mr Box and claiming indemnity under s 151Z(1)(d) of the Workers Compensation Act for such compensation as the employer has paid to the plaintiff.
By way of defence to the employer's action AEA both denies negligence and repeats its assertion that the sole cause of injury to the plaintiff was his own contributory negligence and/or negligence of the employer. The allegation of negligence on the part of the employer is particularised as failure to identify the hazard arising from AEA's use of the explosive powered nail gun on its site adjoining the employer's building site and failure to take reasonable steps to eliminate or minimise any risk to the plaintiff arising therefrom. AEA claims indemnity from the employer in respect of any damages awarded against it in favour of the plaintiff.
The plaintiff's action against AEA, the employer's action against AEA and AEA's cross-claim against the employer have been heard together. Evidence in each proceeding has been received as evidence on all matters in dispute. In each proceeding AEA takes issue with the extent of the plaintiff's injury and ongoing disability as a result of the nail gun accident.

[4]

Circumstances of the accident

I base my findings about the circumstances in which the accident occurred upon written statements and oral evidence of the plaintiff, of Mr Craig Anderson (the site foreman to whom the plaintiff was responsible at No 42) and of Messrs George, Damien and Anthony Alexiou (three brothers who were principals of AEA). I have also relied upon photographs and sketches of the scene of the accident and an email from the late Mr Box to Messrs Alexiou dated 13 November 2012. This was received under s 67 of the Evidence Act 1995 (NSW). A report of Dr Buckland, an expert in the construction industry, is also relevant.
Numbers 40 and 42 are adjacent properties on the north side of Windsor Street, with their frontages facing south. Number 40 is to the west and No 42 to the east. The residences on each are constructed close to the street frontage. The renovations being carried out on both properties in November 2012 involved demolition of structures and excavation at the rear (north) to permit construction of a garage on each property.
On 9 November 2012, from a position at the rear of No 42, Mr Anderson was able to look across the rear of No 40 and observe, on the far side of that property, a common wall between No 40 and No 38. Prior to 1:30 pm on that day Mr Anderson observed employees of AEA affixing plastic sheeting to that common wall, apparently in an endeavour to weatherproof it temporarily. As they performed this work Mr Anderson "heard the charges of a power charged nail gun". The plaintiff also heard these shots and was aware that they were associated with the temporary weatherproofing of the No 38/No 40 common wall, at the rear of those properties.
From about 1:30 pm on 9 November 2012 there was a heavy fall of rain which caused the workmen at No 42, including the plaintiff, to remove power tools and electric extension leads from around the site and place them under cover. The rain lasted for about half an hour. After this the plaintiff, instructed by Mr Anderson, commenced to re-lay the extension leads and to re-position the power tools for resumption of work. For this purpose he was at the rear or northern end of the remaining house structure at No 42. He was on the eastern side of the property furthest away from No 40 and near to a stairway leading to an upper level.
The party wall between Nos 40 and 42 was of double brick construction without a cavity, 230 mm thick. In every fifth course the bricks were laid at right angles to the alignment of the wall, forming a bond between the two single brick component walls. This double brick wall had been constructed in the mid to late 1800s. The bricks were of a material known as sandstock which is "quite soft". They had been laid with limestone mortar, which is "very soft" and has a propensity to crumble.
The rear wall of No 40 was at the same distance back from the street frontage as the rear wall of No 42. On the No 40 side there was a window opening in the rear wall, adjacent and at right angles to the common wall with No 42. On 9 November 2012 Mr Box closed off this window opening with a sheet of plywood. In order to hold the plywood in place he affixed two wooden blocks or cleats to the party wall with No 42. According to his email to Messrs Alexiou of 13 November 2012, he fixed the lower block with two 75 mm nails fired from a Ramset explosive powered nail gun. These nails were driven through the timber block into the party wall on the No 40 side, fired perpendicular to the wall in the direction of No 42. He then fixed the upper block in the same manner. That is, using two more 75 mm nails fired from the gun.
Nails may be fired with a nail gun of the type operated by Mr Box using charges of greater or less explosive power. The charges are colour coded in nine grades, from grey (minimum) to black (maximum). Yellow is in the middle of the range. According to his email Mr Box used yellow charges for the four fixings, two in each block, as described above. He reported in the email that the two blocks were effectively secured by these four shots, without incident and in particular without excessive penetration of the wall. He decided to fire a third nail into the upper block and for this he again used a yellow charge. I find that this was the nail which penetrated the 25 mm timber block and the double brick wall and travelled another 2.5 m across the rear of No 42 to strike the plaintiff in the left temple.
The plaintiff gave evidence that he did not hear the use of an explosive powered nail gun on the adjoining site, No 40, in the period immediately prior to being struck by the nail in question. Other evidence shows that the sound of Mr Box's first four shots, through the timber blocks and into the party wall, would have been audible at least on some parts of No 42. Mr Box's email does not expressly state when he fired the fifth nail relative to the firing of the earlier four. I infer that the fifth nail was fired soon after the fourth, within some minutes. Mr Box did not explain in his email why the fifth nail was fired having regard to the successful fixing of the upper timber block by the third and fourth shots.

[5]

The plaintiff's injuries and treatment

In oral evidence the plaintiff described the effect of the nail impact to his temple as being similar to being hit in the head by a bat. He had been bending down at the waist and was straightening up when the nail struck. The impact jerked his head to the right. He grasped the vertical support of the stair rail, near to which he was standing, and steadied himself. He was not knocked to the ground. He cried out in pain and Mr Anderson came straight to his assistance. The nail was embedded in and protruding from his temple. He was helped to the ground where he lay until paramedics arrived. The plaintiff was "ambulant with assistance" and was conveyed to hospital in a seated position in the ambulance. On the way he was treated with morphine to relieve pain at the site of the injury.
Upon admission to the Emergency Department at St Vincent's Hospital in Darlinghurst at 2:43 pm the plaintiff was assessed for signs or symptoms of brain or other neurological damage. Radiological studies of his head and neck were performed. These showed that a depressed fracture of the skull had been sustained. The bone in the vicinity of his temple had been displaced approximately 5 mm inwards. The nail had penetrated approximately half the thickness of his skull. No damage to the functional tissue of the brain was detected. The dura was not penetrated. There was no intracranial haemorrhage or brain contusion. These radiological results satisfied the on-duty neurosurgeon and neurological registrar that it was safe to remove the nail under local anaesthetic. That was done at 4:30 pm.
The plaintiff complained of continuing headache after the nail had been removed. He was taken from theatre to the Intensive Care Unit (ICU). Twenty-four hours after his admission to the hospital, upon mobilisation of the plaintiff to assess him for discharge, he displayed signs of neurological damage. His gait was ataxic and control and power of his lower limbs was diminished. Further radiological examination of his cervical spine was undertaken to try to find the cause of these symptoms.
A computed tomography (CT) scan on 12 November 2012 showed the plaintiff had a "broad based disc bulge at C3/C4" and that the disc was touching the thecal sac (the membrane which surrounds and encases the spinal cord). Magnetic resonance imaging (MRI) of the cervical spine on 13 November 2012 revealed that the facet joints between the C3 and C4 vertebrae (being synovial joints surrounded by a fibrous membrane or capsule) exhibited osteophyte development (bony growth) and hypertrophy (swelling of the joint capsules). The disc and facet joint pathology at the C3/C4 level was attributable to degeneration which predated the nail impact.
The MRI of 13 November 2012 further showed that the bulging disc was "causing moderate central canal stenosis and mild cord compression" at C3/C4. That is, the central passage through the vertebrae was narrowed by the disc. There was evidence on the MRI scan of oedema (fluid accumulation) or myelomalacia (disorder of white matter, being nerve fibres) in the spinal cord, indicative that compression contact had occurred.
The plaintiff remained in the ICU until 15 November 2012. During that period his headache continued. He was then transferred from ICU to the Sacred Heart rehabilitation facility and remained an inpatient there until 21 November 2012. During the next year he suffered recurring migraine, impairment of balance and reduced control over his lower limbs. By August 2013 Dr Winder (his treating neurological surgeon) had concluded that the plaintiff was at risk of suffering further severe damage to his spinal cord at the C3/C4 level. He recommended an operation to fuse these vertebrae. That was carried out by Dr Winder on 25 November 2013.
It is the plaintiff's case that he continues to suffer recurrent migraine and diminished control over his lower limbs since the operation. AEA disputes the severity and frequency of the continuing migraine symptoms and disputes altogether the alleged ongoing neurological deficit in the lower limbs. AEA denies that such symptoms as have continued after the spinal fusion are attributable to the nail gun accident. It further contends that whatever lasting consequences there may have been from the accident and/or the operation, the plaintiff would have incurred them sooner or later in any event because of the pre-existing degeneration in his cervical spine.
The issues concerning ongoing disability and causation thereof will require closer analysis of the progression of the plaintiff's symptoms and of his treatment, rehabilitation and recovery later in these reasons.

[6]

Duty of care owed by AEA and breach

The plaintiff's claim is pleaded solely as a breach of duty owed to him directly by AEA itself. He does not in terms allege vicarious liability of the company for breach of a duty owed by its employee Mr Box. The Ramset explosive powered nail gun being operated by Mr Box, when used with the yellow grade charges which he had selected, was capable of firing nails through solid materials such as timber and into, if not through, still more dense materials such as masonry. Mr Box knew that. At the latest, by the time he came to fire the shot which caused the plaintiff's injury he knew that the tool used in conjunction with a yellow charge had the capacity to penetrate bricks. This was evident to him from the results of the four shots by which the two timber blocks had been affixed to the party wall.
Mr Box had operated this tool regularly over nine years of employment with AEA. From this I infer the capacity of the device was well known to Mr Box even before he fired the first four shots which fixed the timber blocks. His knowledge is attributable to AEA. AEA was also aware through its principals, Messrs Alexandriou, that an explosive powered nail gun was in use on the site and it ought reasonably to have known of the penetrative capacity of nails fired by this tool using yellow charges.
Self-evidently, as the gun used in conjunction with yellow charges could drive a nail into timber and brick, should a nail be fired into materials of insufficient density and resistance to stop the nail, it could travel at significant velocity through the air. Again self-evidently, a nail so fired could cause physical harm to any person in its path. I have recorded above at [9] my findings that the party wall was constructed of low density masonry, incorporating mortar joints of still lower density. I infer that AEA knew this through Mr Box, he having worked at the surface of the party wall on the No 40 side. As the photographs in Exhibit C reveal, the party wall had no render over the brickwork on the No 40 side. Even if Mr Box had not in fact appreciated the low density and uneven quality of the wall, he (and AEA) ought reasonably to have known of this. I infer from the evidence of Mr Anderson and Messrs Alexiou that the characteristics of brickwork in nineteenth century Paddington terrace houses were at the time well known to builders who worked on such houses in the locality.
Mr Box as the operator of the nail gun and AEA as the company on whose behalf he was using it would owe a duty to persons on No 42 to exercise care with respect to a possible nail strike only if the first prerequisite stipulated in s 5B(1)(a) of the Civil Liability Act 2002 (NSW) is satisfied, namely, that the risk of a nail passing through the wall and striking someone was a risk of which AEA knew or ought to have known. It follows from the facts referred to in [21]-[23] that this prerequisite is satisfied in the present case.
The second prerequisite is that the risk should be "not insignificant": s 5B(1)(b). The likelihood of a nail from the Ramset gun passing straight through the timber block which was being fixed to the party wall and through the wall itself, then continuing with sufficient velocity to cause injury, was quite low. Mr Box recorded in his email report of 13 November 2012 that he had not previously experienced such an event. Nor had any of the three Alexiou brothers or Mr Anderson. But the risk was in my judgment "not insignificant".
It has been said that the statutory question whether the risk is "not insignificant" is a more demanding standard than that which applied at common law, where the question was posed in terms of whether the risk was "not far-fetched or fanciful": Wyong Shire Council v Shirt (1979) 146 CLR 40; [1980] HCA 12. In Shaw v Thomas [2010] NSWCA 169 at [44] Macfarlan JA said (with the agreement of Beazley JA, as her Honour then was, and Tobias JA): The requirement in s 5B(1)(b) that the risk be "not insignificant" imposes a more demanding standard but in my view not by very much.
AEA acknowledged that in Cox v Fellows [2013] NSWCA 206 at [145] and in Garzo v Liverpool/Campbelltown Christian School [2012] NSWCA 151 at [150] the Court of Appeal substantially reiterated the view expressed by Macfarlan JA in Shaw v Thomas. But AEA submitted that these authorities have overlooked a grammatical analysis of the expression "not insignificant" which, if given its due weight, would show that "the statutory formula has moved the standard rather more towards the mid point of the scale [between significant and insignificant] and away from the extremes at either end". AEA submitted that the phrase "not insignificant" in s 5B(1)(b) "should be understood as conveying the idea of noteworthy, of substance (in contradistinction to substantial), readily identifiable".
It is not open to a single judge at first instance to discount the considered views of appellate judges in the cases cited and, on that basis, to adopt AEA's interpretation. The risk of a nail from the explosive power tool penetrating the wall and continuing across the adjoining property was "not insignificant" in my view because there is a rational, practical and sensible analysis of the circumstances upon which the possibility of this occurring can be seen to have been comfortably and substantially above "far-fetched" or "fanciful" as follows: 1. The yellow charges which were in use had sufficient explosive power to drive the 75 mm nails into solid sandstock bricks. It would be eminently possible for nails fired through a timber block into the wall to miss any of the bricks and to encounter the "very soft" mortar joints. 2. It necessarily follows from the configuration of the bricks laid in a bonding pattern on every fifth course that the mortar joints between the bonding bricks and above and below them extended right through the wall. The ratio of the cross-sectional area of these mortar joints extending fully through the wall to the cross sectional area of solid bricks was relatively high in the bonding courses, given that the full thickness joints occurred above, below and adjacent to every brick in each such course. 3. If a nail was fired with a yellow charge into a "very soft" mortar joint extending through the full thickness of the wall it is readily understandable that the nail would meet relatively slight resistance and might pass straight through. 4. The fact that four nails had been fired into the wall without any of them passing through does not imply that the risk of a fifth nail passing through was "insignificant". The first four nails may have struck the centres of sound bricks. The relatively high proportion of full penetration mortar joints to bricks in the bonding courses and the relatively high frequency (one in five) of bonding courses, made the possibility that the fifth nail would encounter a low resistance mortar joint a "not insignificant" risk.
AEA submits that the successful placement of four nails would likely have given Mr Box "confidence that there was no relevant risk of harm" in firing the fifth nail. However Mr Box's confidence is irrelevant. Whether he saw it or not, there was a risk that the fifth nail would find a full penetration soft mortar joint and pass straight through. If he was confident this would not occur then that was false confidence, involving his subjective failure to appreciate a "not insignificant" risk.
Similarly, Mr Anderson's written statement to the WorkCover investigator that "no one would have expected the nail to penetrate the block [of] timber and the double brick wall" is irrelevant. The question whether this was or was not "expected" by anyone does not arise in the application of the legal test. Although realisation of the risk was not "expected", it was nevertheless a "not insignificant" risk.
I conclude that a duty was owed by Mr Box and by AEA to persons at No 42 to exercise care with respect to the risk of a nail passing through and striking someone. Accurate identification of the risk which AEA was required to address in exercise of this duty of care is an essential pre-requisite to consideration of what if any action was required in order to discharge the duty. In other words, the risk must first be identified, leading to definition of the scope or content of the duty, leading in turn to ascertainment of whether there was breach by reason of such action not having been taken: Roads and Traffic Authority of NSW v Dederer (2007) 234 CLR 330; [2007] HCA 42 per Gummow J at [59].
The relevant risk against which AEA was required to take reasonable care, as already mentioned, was that a nail fired from Mr Box's Ramset gun might pass straight through the party wall into which he was firing it, continue across the adjoining property at significant velocity and strike someone. The considerations relevant to finding what precautions the duty of care required AEA to take with respect to that risk are primarily as follows: 1. The degree of probability that harm would be suffered by a person if care were not taken: s 5B(2)(a). That is, the liklihood that a nail fired from the explosive powered tool would pass straight through the wall and that, if it did, it would strike a person on the other side. 2. The likely seriousness of the harm that might be suffered by a plaintiff as a result of this risk being realised: s 5B(2)(b). 3. The burden - cost and degree of difficulty - of AEA taking precautions to avoid the risk of a person on the adjoining property being struck if a nail should pass through the party wall: s 5B(2)(c). 4. The social utility of AEA using the nail gun at No 40.
It is established that the considerations which I have paraphrased at [32] from subs (2) of s 5B of the Civil Liability Act bear upon the scope, or content, or requirements for discharge, of the duty of care. Hence they bear upon whether a breach has occurred. This is so notwithstanding that the heading "Division 2 - Duty of Care" appears immediately before s 5B: Adeels Palace Pty Ltd v Moubarak (2009) 239 CLR 420; [2009] HCA 48 at [13]; Grills v Leighton Contractors Pty Ltd [2015] NSWCA 72 at [93]-[95].
The question of what precautions were reasonably required of AEA in discharge of its duty is to be approached on a prospective basis, looking forward from before the plaintiff was injured, not looking back with hindsight derived from the facts that a nail passed through the party wall and thereafter struck the plaintiff, on 9 November 2012: Vairy v Wyong Shire Council [2005] HCA 62 at [60] (Gummow J) and [126]-[129] (Hayne J); Adeels Palace Pty Ltd v Moubarak at [40]; Neindorf v Junkovic (2005) 80 ALJR 341; [2005] HCA 75 at [93].
Addressing the matters listed in [32], I find as follows: 1. With respect to the probability of harm occurring if care should not be taken, I have stated my conclusion that the probability of a nail passing through the 25 mm of timber and through the wall was low but "not insignificant". The probability of harm resulting to some person if this should occur would be substantial because No 42 was an active work site and because the velocity at which the nail might travel would render it a dangerous projectile. 2. The likely seriousness of harm flowing to any person who might be struck by a nail penetrating through the wall and across the adjoining property would be considerable. I infer that such a projectile could, for example, take out a person's eye. The serious injuries suffered by the plaintiff are illustrative of what could occur. 3. The primary precaution which the plaintiff has asserted AEA should have taken was to post a lookout or "spotter" who would take up a position from which he would have a line of sight into the adjoining property and also be able to make himself heard by Mr Box. This could have been done with negligible diversion of labour from other tasks on the building site at No 40. 4. The social utility of the use of the nail gun was modest. There were available several alternative means of affixing the timber blocks to the party wall without firing explosive powered nails into it: see [45] below. Mr George Alexiou gave evidence that a nail gun shot would take 30 seconds whereas a common alternative method of fixing to masonry would take up to 5 minutes. This is insignificant.
I conclude that AEA's duty to exercise reasonable care to avert the identified risk required that, before firing, Mr Box should have ascertained whether any person was in the path which a nail might follow if it should pass through the wall, including a departure from the direct line of fire such as might result from the nail being partially deflected. Further, the duty required that AEA should warn any such person to move to a safe location and that the gun should not be fired until that had occurred. This would have required that AEA appoint a spotter to act as described above at [35(3)]. AEA breached this duty by failing to make any check for persons who might be in the line of fire before discharging the tool and by failing to cause such persons to move to safety. The injury by nail impact with the plaintiff's temple was directly caused by the breach and AEA is therefore liable to the plaintiff in negligence for damages.

[7]

Not an obvious risk

At pars 20 and 21 of AEA's defence it is alleged that the plaintiff's injury resulted from the realisation of an obvious risk. The following sections of the Civil Liability Act are invoked: 5F Meaning of "obvious risk" (1) For the purposes of this Division, an obvious risk to a person who suffers harm is a risk that, in the circumstances, would have been obvious to a reasonable person in the position of that person. (2) Obvious risks include risks that are patent or a matter of common knowledge. (3) A risk of something occurring can be an obvious risk even though it has a low probability of occurring. (4) A risk can be an obvious risk even if the risk (or a condition or circumstance that gives rise to the risk) is not prominent, conspicuous or physically observable. 5G Injured persons presumed to be aware of obvious risks (1) In proceedings relating to liability for negligence, a person who suffers harm is presumed to have been aware of the risk of harm if it was an obvious risk, unless the person proves on the balance of probabilities that he or she was not aware of the risk. (2) For the purposes of this section, a person is aware of a risk if the person is aware of the type or kind of risk, even if the person is not aware of the precise nature, extent or manner of occurrence of the risk. 5H No proactive duty to warn of obvious risk (1) A person (the defendant) does not owe a duty of care to another person (the plaintiff) to warn of an obvious risk to the plaintiff. (2) This section does not apply if: (a) the plaintiff has requested advice or information about the risk from the defendant, or (b) the defendant is required by a written law to warn the plaintiff of the risk, or (c) the defendant is a professional and the risk is a risk of the death of or personal injury to the plaintiff from the provision of a professional service by the defendant. (3) Subsection (2) does not give rise to a presumption of a duty to warn of a risk in the circumstances referred to in that subsection.
None of these sections has any application to the present case because, in the circumstances proved, the risk of a nail being fired through the party wall and across No 42 Windsor Street could not be regarded as one that "would have been obvious to a reasonable person in the position of" the plaintiff. I am satisfied on the balance of probabilities that the plaintiff did not know a nail gun was in use at No 40 at the time he was struck or in the immediately preceding period. I accept his evidence that he did not hear any shots prior to the one which resulted in the nail embedding itself in his temple and that he did not even hear that shot. The earlier shots, fired before 1:30 pm into the common wall of No 38/ No 40, were fired in a direction away from No 42. The plaintiff's knowledge that a nail gun was in use at that time and in that manner is not relevant to the alleged "obvious risk" of the usage of the nail gun after 1:30 pm.
I accept that Mr Box's first four shots were fired shortly before that which caused injury. Mr Craig Anderson, on the same site as the plaintiff, heard them. But it is possible that sound travelled between the two buildings in such a way that the report of a nail gun might be heard at one location and not at another. I therefore see no reason to doubt the plaintiff's evidence that he did not hear the first four shots. I found him in relation to this matter and in all respects completely candid. I did not detect in his manner of giving evidence a single instance of evasion, prevarication, contradiction or artifice. In the witness box the plaintiff exhibited an uncomplicated, laconic and humble directness throughout.
Even if the plaintiff (or any reasonable person in his position) had heard the nail gun in use before he was shot by it, the risk of a nail being fired at him through the wall would not have been obvious. No one located where the plaintiff was standing at No 42 could have known, even from hearing reports of the nail gun, that it was being fired against the party wall with the potential for a penetrating nail to pass through and across No 42. With the party wall blocking any view into No 40 it would not have been possible for the plaintiff or any reasonable person in his position to know that the gun was aimed in a direction dangerous to him, rather than towards No 38, or vertically down (for example to secure something to a floor within No 40), or longitudinally through the building towards the street frontage or towards the rear, or vertically upwards (for example to secure something to the underside of the joists of the first floor or to the underside of roof beams or trusses).
The defendant has pleaded that because the risk was obvious AEA "owed no duty to the plaintiff and is not liable in negligence or at all". But even if the risk was obvious, s 5H would only operate to eliminate a duty to warn: Angel v Hawkesbury City Council [2008] NSWCA 130; (2008) Aust Torts Reports 81-955 at [83] (Beazley and Tobias JJA; Spigelman CJ, Giles and Campbell JJA agreeing); Glad Retail Cleaning Pty Ltd v Alvarenga (2013) 86 NSWLR 191; [2013] NSWCA 482 at [57] (Sackville AJA; Barrett and Gleeson JJA agreeing). The scope of AEA's duty of care in the circumstances required it to do more than merely warn. I have found that the duty required it to refrain from firing a gun at all until all persons were out of the line of fire. The duty was in that respect breached.
I have dealt at length with AEA's case on "obvious risk" and ss 5F-5H only because it is pleaded and has been pressed. However this part of AEA's defence is in my view manifestly untenable and lacking in common sense. It involves the proposition that a builders' labourer at No 42 ought to have considered himself so obviously at risk of a tradesman on the adjoining site, whose activities he could not see, firing explosive powered nails through the wall that the tradesman need not even shout a warning when he was about to fire. On the facts as I find them I have no hesitation in rejecting that proposition.

[8]

The risk was not "inherent"

In pars 22 and 23 of its amended defence AEA alleges that the injury to the plaintiff as a result of the nail striking and embedding itself in his temple "was caused or contributed to by the materialisation of" a risk which could "not have been avoided by the exercise of reasonable care on the part of AEA". AEA relies upon s 5I of the Civil Liability Act, as follows: 5I No liability for materialisation of inherent risk (1) A person is not liable in negligence for harm suffered by another person as a result of the materialisation of an inherent risk. (2) An inherent risk is a risk of something occurring that cannot be avoided by the exercise of reasonable care and skill.
Again I find unrealistic the suggestion that the risk of shooting in the head with a nail gun a worker on an adjoining building site could not have been avoided by the exercise of reasonable care. If the materialisation of such a risk was truly unavoidable as an incident of use of a nail gun, then reasonable care in the performance of building work would require that use of the tool be abandoned. Such an explosive powered tool is not indispensable to construction work and was not so at the time of this incident.
There are other ways of fixing timber blocks to masonry walls. A common method is to drill a hole in the brickwork with a rotary percussion drill, insert a plastic wall plug or a timber dowel and drive a screw through the timber which is to be affixed and into the wall plug or dowel. Alternatively a dynabolt may be used, inserted into a pre-drilled a hole in the masonry and fixed in place by the expansion of a sleeve around the bolt, which occurs when it is tightened. A third method is to drill a small diameter hole and drive into it a masonry nail with a pre-attached plastic sleeve which expands as the nail is driven and grips the internal diameter of the hole. All of these alternatives are matters of common knowledge. They can be implemented with fixings which are widely used in Australia and are readily available as stock items from retail hardware stores throughout the country.
For these reasons I reject AEA's defence of inherent risk under s 5I of the Civil Liability Act.

[9]

No contributory negligence of the plaintiff

By pars 18 and 19 of its amended defence AEA has pleaded that the plaintiff's injury resulted from contributory negligence on his part and has claimed a reduction of 100% of its own liability. The particular of contributory negligence is failure to wear a construction safety helmet, which is said to have involved exposing himself to an "obvious risk" and to an "inherent risk" within the meaning of the Civil Liability Act. In par 25 of AEA's amended defence to the employer's amended statement of claim a further particular of contributory negligence is given, namely, failure of the plaintiff to warn his employer that he could hear explosive power tools being deployed in the adjacent premises.
I have found that the plaintiff was unaware of the use of an explosive powered nail gun in the adjoining premises during the period shortly before and leading up to the firing of the shot which struck him: see [12], [39]. I therefore reject the additional particular provided in AEA's defence to the employer's claim. Even if the plaintiff had heard any of the four shots of the nail gun fired immediately before the one which hit him, I am satisfied that he could not have been aware that a nail gun was being used against the party wall aimed towards and across No 42, towards the location where the plaintiff was standing (see [40]). He could not possibly have known that (and nor could any reasonable person in his position) because the activities of Mr Box were concealed from his view by the party wall and because neither Mr Box nor anyone else on behalf of AEA issued any warning to the workmen on No 42.
Section 5R of the Civil Liability Act provides as follows: 5R Standard of contributory negligence (1) The principles that are applicable in determining whether a person has been negligent also apply in determining whether the person who suffered harm has been contributorily negligent in failing to take precautions against the risk of that harm. (2) For that purpose: (a) the standard of care required of the person who suffered harm is that of a reasonable person in the position of that person, and (b) the matter is to be determined on the basis of what that person knew or ought to have known at the time.
From the above findings that the plaintiff, acting reasonably, was unaware of the risk to which he was exposed by AEA's activities, it follows that a reasonable person in his position would not have taken any precaution against the risk. I have earlier rejected AEA's contentions, which are repeated in support of its contributory negligence argument, that the risk was "obvious" and/or "inherent" in the statutory sense: see [37]-[4645] above.
The fact that the plaintiff was not wearing a construction safety helmet does not constitute lack of reasonable care with respect to the risk which is under consideration. I am satisfied that neither the plaintiff nor anyone else at No 42 was undertaking any activity at the relevant time which created any risk against which the exercise of reasonable care by the plaintiff for his own safety called for a construction safety helmet to be worn. Even if there had been such activity at No 42, for example overhead work being undertaken with the risk of tools or materials falling from above, failure of the plaintiff to take the precaution of wearing a hard hat to avoid injury from such activity would not be relevant. Consistently with the common law, s 5R is concerned with any failure "to take precautions against the risk of that harm", that is, against the risk which in fact materialised.
The plaintiff would not be defeated in his claim by failure on his part to take precautions against a risk of a kind and from a source entirely different from that which came to pass in the firing of the nail. Assuming he was careless for his own safety with respect to construction risks associated with, for example, overhead work at No 42, no such risk eventuated. AEA cannot opportunistically invoke the failure to wear a hard hat as contributory negligence in relation to a risk which AEA's activities created, of which the plaintiff was unaware and against which he was therefore not reasonably required to take any precaution.
For these reasons I find no contributory negligence on the part of the plaintiff.

[10]

No breach of duty by the employer

Section 151Z(2) of the Workers Compensation Act is concerned with situations, such as the present, where an injured worker has brought proceedings against a third party (in this case AEA) for damages in respect of an injury for which compensation is payable by the worker's employer under the Act. The subsection provides for adjustment to the amount of damages the worker may recover from AEA if it should be found that the employer was a tortfeasor liable in respect of the same damage. AEA has invoked this provision by par 24 of its amended defence to the plaintiff's statement of claim, alleging that the employer was "wholly liable for the accident and its contribution as a joint tortfeasor is 100%".
Further, in AEA's defence to the employer's amended statement of claim (in the separate proceeding which the latter has brought under 151Z(1)(d) of the Workers Compensation Act to recover the compensation which the employer has paid to the plaintiff) AEA has alleged that the employer breached its duty of care owed to the plaintiff.
I reject AEA's contention, in both proceedings, that the employer breached its duty of care owed to the plaintiff. I hold that the relevant risk, as identified at [32] above, was not reasonably foreseeable to the employer. That is, it was not a risk of which the employer knew or ought to have known. Accordingly, there arose no duty to exercise care with respect to this unforeseeable risk and there is no liability in negligence: Civil Liability Act, s 5B(1)(a). I so hold for the following reasons.
First, I am satisfied that the employer, through its site manager at No 42 (Mr Anderson), did not in fact know that the nail gun was being used against the party wall and perpendicular to it so that its line of fire was across No 42 where he and the plaintiff were located. Nor could a reasonable person in Mr Anderson's position have known that. The wall blocked his view, just as it blocked the plaintiff's view.
Secondly, Mr Anderson (and hence the employer) did not know and could not reasonably have known what grade of charge was being used, or that the task was to affix timber to the wall, or what thickness of timber was involved. In short, neither Mr Anderson nor any reasonable person in his position could have had any understanding of the risk of complete penetration of a nail through the wall, even if he had known that nails were being fired perpendicular to it in the direction of No 42.
In the absence of any warning from AEA's personnel or any announcement of what Mr Box was doing, the mere possibility of someone firing a nail perpendicular to the sandstock party wall in the direction of No 42 would not cause a reasonable person in Mr Anderson's (or the employer's) position to take any precautions.
I am satisfied that Mr Anderson could not have inspected the location at which Mr Box was working or the manner in which he was using the nail gun without entering upon No 40. That would have required him to go out into Windsor Street or into the rear lane and then make his way into No 40, either through the front entrance or the rear. He would not have been entitled to enter as of right nor to give any instruction to AEA personnel about taking precautions. Having ascertained what was taking place he would have had to seek AEA's cooperation to take reasonable care for the occupants of No 42 by using a spotter as previously described, or alternatively instruct the plaintiff and anyone else at No 42 to vacate the site.
A reasonable person in the employer's position would not have taken the initial and essential steps of entering upon No 40 to evaluate the activity there, from which any other steps would follow, in circumstances where no warning had been issued by those who were working on No 40 and where there was no more than a bare possibility that a nail gun might be being used by AEA in a line of fire which posed a risk for the plaintiff and other persons at No 42.
AEA's submissions in support of its case that the employer breached its duty of care to the plaintiff placed great emphasis on the non-delegable nature of the employer's duty and on the employer's responsibility to provide a safe place of work and system of work, even in respect of the activities of third parties. AEA sought to extend the scope of the employer's duty where a third party "is carrying on work in the near vicinity of the place of work where the employer has put the employee to work, and the employer knows or ought to know that the work so being carried out is capable of exposing its employee to personal injury". In such a case, AEA submitted, the employer has an obligation to inform itself of the third party's activity "so far as it has a capacity to impact upon" its employee, so that the employer is "by one means or another able to take reasonable care to ensure the safety" of its employee.
These propositions may be accepted at a general level but on the facts as I find them the critical premise is not established. AEA has not shown that "the employer [knew] or ought to [have known] that the work so being carried out [by AEA] [was] capable of exposing its employee to personal injury". AEA relies upon the fact that Mr Anderson heard the first four nail gun reports. This fails to take account of the circumstance, to which I have earlier adverted, that no reasonable person in Mr Anderson's position ought to have known that the gun was being fired in the direction of No 42, without warning (see [40]).
AEA's argument that the employer, through Mr Anderson, ought to have known that Mr Box's use of a nail gun on No 40 exposed the plaintiff to danger results from hindsight reconstruction. To illustrate, one may consider hypothetical facts which do not involve the events that actually occurred. If Mr Anderson had heard a jackhammer in use on No 40, the employer's duty of care would not have required investigation to see whether AEA was undermining the foundations of the party wall and might cause it to collapse on the plaintiff. If he had heard timber being sawn on No 40 the employer would not have been under a common law duty to investigate whether joists or trusses were being removed which might cause the party wall to collapse through loss of lateral support. In short, the employer would have needed more knowledge of what was occurring on No 40 than a mere understanding that a nail gun was in use, before its duty of care to the plaintiff would have required it to take precautions against this third-party activity.
AEA relied upon Kondis v State Transport Authority (1984) 154 CLR 672; [1984] HCA 61 as authority for the proposition that an employer's duty to provide its employee with safe place of work and safe system of work may be breached if the employee is required to work in an area where he is at risk from third-party activities without warning or direction. It was submitted that "conceptually the liability of [the employer] is indistinguishable from that in Kondis". This submission was sought to be justified upon the basis that "[the plaintiff] was at risk of injury if [power charged nail guns] were used on the common wall; he wasn't to know he was at risk, but [the employer] knew he was, and he could and should have been told (or directed) to keep away from the area of risk".
The argument fails because I find that the employer did not know the explosive powered nail gun was being used on the common wall or that the plaintiff was risk and was not in such a position that it ought to have known those things. In Kondis v State Transport Authority the mobile crane, from the jib of which a metal rod fell and caused injury to the employed workman, was being operated by a third party on and over the employer's railway yard where the workman was engaged. The crane was being operated pursuant to a contract of engagement by the employer. This took place in full sight and knowledge of the employee's supervisors. The employee was not warned or directed to refrain from standing under the crane jib, either by the crane operator or by the employer (through the supervisors). The risk of the metal rod falling on the employee, as in fact occurred, was obvious. Although the primary judge found that at the time of the accident the employee acted under the control of the third-party crane driver, the employer's duty of care nevertheless required it to adopt a safe system of work. The non-delegable duty was not discharged by leaving the employee to be directed by the crane operator. Those facts are a far cry from what is under consideration in the present case.
I reject AEA's claim for contribution from the employer as alleged tortfeasor liable in respect of the damage. I reject AEA's defence to the employer's claim for recovery of the workers compensation payments which it has made to the plaintiff.

[11]

Causation of damage to the plaintiff's spinal cord, in medical terms

Two neurosurgical specialists called by the plaintiff, Professor Fearnside and Dr Winder, are of the opinion that the MRI of 13 November 2012 and the plaintiff's altered gait and compromised balance as observed by the physiotherapists in the ICU on and after 10 November 2012 indicate that the sudden movement of the plaintiff's head when he was struck by the nail caused the pre-existing disc bulge at C3/C4 to compress his spinal cord at that level.
Professor Fearnside considered that the nail strike to the plaintiff's temple "must have caused some movement of his head". He based this view upon consideration of the energy of the impact, which was indicated by the embedding of the nail in the plaintiff's skull and the resultant depressed fracture. He gave this opinion as to the causal mechanism of the compression injury to the plaintiff's spinal cord, which he considered was in evidence in the MRI scan of 13 November 2012: if he had [-] and he did have [-] cervical canal stenosis, or a narrowing of the vertebral canal at the C3‑4 level, which […] would have [been] pre‑existing and which was present [in] the MRI scan on 13 November, then that would certainly act as a vulnerability to injury, such that the energy of impact would necessarily or could be less than that which would cause the same injury in a normal neck. So his neck at that time wasn't normal.
Professor Fearnside said: when there's a discreet injury to the spinal cord there is swelling, that is to say, there's transfer of fluid and there's more water in the spinal cord at that level which can disrupt the nerve fibres. And there are certain inflammatory mediators which are also released from the injured tissue. The Professor said that the excess water in the spinal cord associated with injury to it would cause an "increased signal" in the MRI scan. Such an increased signal was reported in the scan of 13 November 2012, at C3/C4.
The Professor interpreted the MRI report as having revealed a "circumferential narrowing of the vertebral canal", contributed to by both the bulging disc and the bilateral osteophyte complexes and facet joint hypertrophy. He said with respect to the facet joints: the capsules get thicker and the capsules can intrude on the vertebral canal causing it to narrow.
Professor Fearnside further elaborated his opinion as to the causal mechanism as follows: where there's narrowing [of the spinal cord canal, by bulging of a disc and/or hypertrophy of facet joint capsules], that can cause a blow to the spinal cord if [-] it's of sort of a momentary movement of the vertebral column at that level and it doesn't need to be a sustained compression, it can just be a single blow that can cause the spinal cord injury.
Professor Fearnside described the oedema in the spinal cord, revealed by the increased signal on the MRI scan, as an inflammatory response to the compression caused by the plaintiff's head being displaced sideways and being rotated in response to the nail impact. His evidence about the duration of physiological damage in the cervical spine and in the spinal cord and C3/C4 was as follows: Q. Is there more to the inflammatory response than that manifestation of fluid, is there swelling somewhere else or? A. There can be swelling within the cord but I don't think we have any evidence of this as reported in that MRI scan. The inflammatory response is short lived and would resolve over ten to 14 days. Q. What about reaction in the disc and the facet joints, can a blow of the type that you described contribute to them remaining swollen or inflamed? A. No, I don't think so, no. Q. So why would there be symptoms continuing after the inflammatory response to the blow has subsided? A. Because the longer term effect is the result of damage to the nerve fibres running up and down [the spinal cord] and that was manifest by his muscle weakness and his difficulty with balance and gait. So the acute inflammatory response resolves […] [I]f there's physical disruption of the nerves that will cause […] scarring […] within the spinal cord itself, so that causes some permanent disruption of the nerve fibres which result[s] in neurological signs being manifest. Q. The damage to those fibres affects the way in which they innervate muscles of the lower limbs? A. Correct […] and over time some of this is reversible and some of it's not reversible and I suspect the reason Dr Winder deferred the surgery was to try and make that assessment as to what degree of recovery would eventually occur.
Dr Winder provided a very similar analysis of how the nail impact would have caused sudden movement of the head and neck, resulting in compression contact of the disc or some other part of the C3/C4 vertebral joint with the spinal cord and damage to it, manifesting in the neurological symptoms of the lower limbs. He inferred that the impact of the nail would have caused "hyperextension or flexion, meaning that the head will go back or to the side". The doctor said that it was "entirely reasonable" that the neurological deficits observed and symptoms complained of after the accident (including loss of power and control in the lower limbs) would have been caused by the nail impact, knocking his head to the side with force comparable to that from being hit by a bat, in response to which he had taken hold of one of the vertical members of the staircase balustrade to steady himself.
Dr Winder said: where people who have a narrowing of their spinal canal, or with a disc protrusion, they suffer either a flexion or extension injury the cord gets hit up against the disc because the space is narrowed and you can get a degree of inflammation or blood product which can cause changes within the cord.
This mechanism of injury to the spinal cord was further explained by Dr Winder: Q. With a flexion or hyperextension injury of the type you've described could the disc push against the spinal cord? A. Absolutely, because the spinal cord is surrounded by a thin layer of cerebral spine fluid and then you have the dura, which is […] essentially like a rice paper roll holding all the fluid together. When you've got a bulge coming in which is very obvious on the MRI scan [of 13 November 2012] it doesn't take much for that to be hitting right up against the cord, and it's been shown on many studies that as soon as you extend the neck or go into, you know, a flexion that that's enough to actually displace the cord right up onto that bulge. So, if the bulge is here, the cord will hit up against it. Q. And that would be the bruising mechanism? A. Yep.
Dr Winder considered it irrelevant whether the part of the plaintiff's cervical spinal cord which showed increased MRI signal on 13 November 2012 might already have had some pathology, prior to the nail gun incident of 9 November, which would similarly have exhibited increased signal if an MRI scan had been done at an earlier time. He based that opinion upon the circumstance that the plaintiff was asymptomatic prior to the accident. The doctor said: the causal relationship between an injury of extension and developing neurological sequelae is pretty clear cut in my opinion because it's irrelevant whether [the feature associated with the increased MRI signal] was there before or not, [it] still has been made worse by this injury.
In Dr Winder's opinion the part of the plaintiff's cervical spinal cord which exhibited increased MRI signal was affected by either oedema or myelomalacia as a result of the hyperextension/flexion injury. He explained that a compression injury to the spinal cord could cause an inflammation of glial tissue, which is interspersed with and holds together the nerve fibres of the cord. He referred to this as gliosis which, he said, may "cause just a gradual scarring of sorts … and it [the glial tissue] actually shrinks down a little bit".
Dr Cochrane, a neurosurgeon called by AEA, agreed it was "quite plausible and quite likely" that the nail impact would have "jerked" the plaintiff's head and "quite likely" that this would have brought the bulging disc at C3/4 into contact with the spinal cord and "caused damage" to it. He said "absolutely conceptually such a thing would irritate or damage the spinal cord". However he said he "couldn't comment" on the degree of damage that might have been done if that occurred. He agreed that on the MRI scan of 13 November 2012 "the increased cord signal would indicate either oedema or myelomalacia at that point" but he "couldn't comment on the timeframe" of that pathology or whether it was pre-existing.
Dr Cochrane had three bases of reservation against accepting that cord damage occurred at the time of the known impact and was the cause of the neurological disorder of the plaintiff's legs observed from the afternoon of 10 November 2012 and which has afflicted the plaintiff thereafter. The first basis was the absence of any record of neurological signs exhibited during the first 24 hours following admission. The second was Dr Cochrane's view that a CT scan of the plaintiff's cervical spine taken in September 2007 may indicate earlier cord damage, probably from a snowboarding accident in about 1998. Dr Cochrane's third basis was that fluctuating symptoms during 2013 raised for him doubts about whether the neurological symptoms stemmed from cord damage on 9 November 2012.

[12]

Absence of record of neurological symptoms immediately following admission

AEA's counsel cross-examined the plaintiff's medical experts on the St Vincent's Hospital records, which indicate that no loss of control or power in the plaintiff's legs was detected by medical staff during the first 24 hours after his admission. The records show that he suffered no loss of consciousness in connection with the nail gun incident. His Glasgow Coma Score was 15/15 when the ambulance brought him to the Emergency Department. A triage assessment on admission did not reveal any clinical signs of change to his spinal cord at the cervical level. Both arms and legs were found to have normal power. This was assessed with the patient lying down.
At 2:50 pm on 9 November 2012 Dr Brooks, an unaccredited neurosurgical registrar, examined the plaintiff. He recorded that power in all four limbs was "5/5", again assessed with the patient supine. Yet another examination was made at 5:30 pm on 9 November 2012, upon the plaintiff arriving at the ICU after removal of the nail. Power was again found to be "5/5" in all limbs. At this time reflexes were recorded as "++" in both arms and "++↓" in both legs. Dr Winder gave evidence that these abbreviations signified elevated reflexes consistent with spinal cord involvement. Dr Cochrane interpreted the abbreviations as indicating normal reflexes. I am not able to resolve this difference without evidence from the person who made the observations and wrote the notes. I therefore cannot determine whether or not the plaintiff was hyperreflexive late on the afternoon of his admission.
The plaintiff continued to complain of pain late in the afternoon of 9 November 2012 and was given morphine at intervals. The following morning, 10 November 2012, he was able to mobilise, apparently with assistance, to the toilet and to wash. At 9:25 am a further examination again showed he was able to move "all limbs to command" and had "5/5 power" in each case, with nil deficit. Nursing notes from that time record that he was "mobilised". A CT scan of the brain was carried out at 10:17 am. The depressed fracture of the skull remained visible on this. The radiologist's report stated that no intracranial haemorrhage could be identified nor any infarct or hydrocephalus (fluid in the cavities within the brain).
At 2:00 pm on 10 November 2012 the plaintiff was seen by another unaccredited neurosurgical registrar, Dr Lukins. He discussed with Dr Winder both the recent CT scan of the brain and his own clinical observations of the patient. As recorded, those observations were that the plaintiff was stable and continued to complain of a mild to moderate headache. Dr Winder considered that the plaintiff could be discharged the next morning, 11 November.
In accordance with usual hospital procedure the plaintiff was seen by a physiotherapist at 2:30 pm on 10 November 2012, following Dr Lukins' visit. The purpose of this was to verify his mobility and to advise him upon self care before discharge. The physiotherapist noted that the plaintiff's gait was abnormal when he walked with one person assisting him. He adopted a wide base of support in his stance and exhibited elevated lateral sway and reduced stride length. "Significantly reduced strength" in all limbs was found as well as reduced sensation and reduced high-level balance. The physiotherapist assessed him "not safe for [discharge] home at this time". He remained an inpatient.
On 12 November 2012 Dr Lukins recorded that the plaintiff still complained of headache and that nursing staff reported him to be unsteady. The doctor ceased opioid pain medication and prescribed Panadeine Forte instead. Following further discussion with Dr Winder, Dr Lukins considered that the plaintiff could be discharged but a physiotherapist found that he still felt unsteady, that his hands shook as he attempted to put on shoes, that he required assistance walking and that his steps were slow and shuffling. He was assessed not safe to attempt stairs.
After the further CT scan of 12 November 2013 (see [16]), concerns regarding his mobility continued into 13 November 2012 when the MRI scan was undertaken with results as referred to at [17].
Professor Fearnside did not consider that his opinion on causal nexus between the nail gun accident and the plaintiff's neurological problems was invalidated by the circumstance that neurological deficit in the lower limbs was not picked up in the hospital until 24 hours after admission. The doctor explained why that delay was not significant as follows: Because he was initially seen in the emergency department, at which time he would have been […] in bed. Focus was on what was going on with his head. He was then moved to intensive care where he was observed overnight, so he was in bed and it wasn't until he was mobilised the next day that it was realised that he couldn't walk properly. So while he was in bed it's axiomatic that he wouldn't be able to be assessed for gait or balance.
Dr Winder said much the same thing: … you talk about a general neurological assessment when a patient comes in. The patient has been in intensive care where they are assessed initially, and before they were discharged from intensive care, and they are assessed from a neurological basis while they were in bed. Can you move your arms? Can you move your legs? Yes. Neurologically intact, and that's how it goes. He then gets up to the ward, and he is able to sit out of bed, he is able to mobilise, when he is done with the physiotherapy and then it's identified that he's got a gait assessment abnormality, which wasn't identified before because we don't assess that in ICU, so once it's been identified it is a problem which needs to be addressed, and he subsequently has gone on to have [magnetic resonance] imaging, I believe, after that.
That evidence of Professor Fearnside and Dr Winder satisfies me that the absence of any observation of symptoms of spinal cord trauma in the first 24 hours after admission is not a sound basis for inferring that such trauma had not been sustained or for rejecting the doctors' opinion that the symptoms, as in due course observed and recorded, had been caused by the mechanism of spinal cord damage which Professor Fearnside and Dr Winder describe. Their evidence about the limitations of the examination of the patient after his first admission is entirely consistent with the hospital records.
Further, the opinion of these medical experts is that the inflammatory response of the spinal cord to a compression injury would not be instantaneous so that resultant neurological deficits would not necessarily have manifested themselves in the first 24 hours after injury, even if rigorously tested for. For example, Dr Winder said: Q. If there were inflammation, it would give rise to a condition giving rise to a signal cord change within minutes, or an hour or so, relatively quickly? A. It's entirely variable. You know, I've seen the fluctuation where it can be instantaneous, and patients come in with significant oedema, and I've seen other cases where it can develop over a week. Q. It is more likely to be instantaneous or within minutes or hours, or less likely? A. It's entirely variable.
There is no suggestion, in the hospital records or elsewhere in the evidence, that the symptoms of cord trauma detected on 10 November 2012 were anything other than genuine. Moreover they accorded with Professor Fearnside's and Dr Winder's hypothesis of causation (namely, compression of the cord by a disc bulging into the stenosed spinal canal as a result of neck extension/flexion). That hypothesis was immediately and strongly supported by the MRI scan conducted on 13 November, showing increased signal in proximity to the bulging disc. It is significant that nothing had been done to the plaintiff in the interval after the nail gun accident and up to the time at which the neurological symptoms in his legs were first identified which could constitute an alternative mechanism by which those symptoms could have been caused at that time.
Dr Cochrane considers that the absence of any report or record of ataxia or other neurological signs during the first day of the plaintiff's admission to St Vincent's Hospital is an indication that the neurological deficits in his legs did not arise from spinal cord injury sustained in the nail gun accident. He said that in his experience the most profound neurological deficit from traumatic injury to the spinal cord is normally present "immediately or very soon after the primary traumatic event". He said this "may be not instantaneous but certainly with an hour or two of the event there should be maximum neurological deficit". However in the same passage of his evidence he acknowledged that "conceivably, there could be a relatively minor trauma, not that severe, not clinically even initially, and then the delayed deterioration due to swelling or oedema, but that deterioration due to swelling or oedema should therefore resolve as the swelling resolves".
This evidence is not sufficient to cause me to conclude that the history of emergence and identification of the plaintiff's symptoms is inconsistent with the mechanism of causation to which Professor Fearnside and Dr Winder have attested. Their conclusion that the symptoms were caused by cord damage sustained upon the nail impact to the head is strongly supported by a rational and scientific hypothesis, by temporal connection and by absence of any other explanation of why or how the plaintiff's symptoms emerged when they did. They have explained to my satisfaction that the absence of any report or record of altered control over the lower limbs during the first 24 hours of hospitalisation is not inconsistent with their conclusion.

[13]

Spinal cord damage not caused by previous incident

The plaintiff was born on 23 July 1984. He has acknowledged that when he was either 14 or 15 years of age (that is, in 1998 or 1999) he was involved in a snowboarding accident which caused him temporary paralysis. It is also common ground that on 17 September 2007 he was seriously assaulted and knocked to the ground, striking the back of his head on a paved surface. Upon hospitalisation on the latter occasion CT imaging of his cervical spine was performed. The radiologist's report on that occasion noted: no acute fracture or disturbance of alignment. The pre-vertebral soft tissues outline normally.
The plaintiff tendered an image from the CT scan of September 2007, being a sagittal (side view) cross-section. This appears to show a small area of high radio opacity in the spinal cord at the C3/C4 level. In a report of 3 November 2017 Dr Cochrane expressed the opinion that this "could represent previous blood product, and on balance of probability I consider it likely that [the plaintiff] had pre-existing spinal canal stenosis and a proximal cord lesion predating the work-related injury of 9 November 2012". Dr Cochrane thought that what he interpreted as a blood speck in the CT image was probably associated with the earlier snowboarding accident rather than with the September 2007 assault.
Dr Winder disagrees with Dr Cochrane's interpretation of the 2007 CT image for four reasons. First, in Dr Winder's view CT scans notoriously exhibit artefacts. He considers that the area of high opacity is likely to be an artefact rather than evidence of blood product. Secondly, he reviewed the axial images from the same CT study and found no indication of blood product or lesion on the axial view. In his opinion that view would be more accurate for identifying a spinal cord lesion if one were present. The conflicting evidence of the doctors on these first two points is evenly weighted and I am not able to determine whether earlier spinal cord damage is or is not shown in the 2007 CT image on the basis of these points. Dr Cochrane did not accept Dr Winder's reading of the relevant area of opacity in the sagittal aspect as a mere artefact. He construed this part of the image as "an isolated, somewhat ovoid region of high density" whereas he thought "an artefact will typically be a streak phenomenon". Further, he interpreted the axial image as including "a streak of high density within the substance of the anterior spinal cord" apparently, in his view, corresponding with the sagittal scan.
Thirdly, Dr Winder considers that if there were blood product or a lesion in the spinal cord dating from September 2007 or earlier, the plaintiff would have had associated neurological symptoms from that time. It is common ground that he did not exhibit symptoms consistent with such spinal cord damage in September 2007 when the scan was done or any time prior to 9 November 2012. Fourthly, the radiologist's report on the 2007 scan did not suggest that the area of high radio opacity represented blood product. On the balance of probabilities, I am persuaded by these third and fourth considerations to accept Dr Winder's view that the 2007 CT scan is not evidence of spinal cord damage at the cervical level dating from (at latest) 2007. I find the absence of neurological symptoms prior to 9 November 2012 particularly compelling. As Dr Winder said, that circumstance renders the disagreement over radiological interpretation inconsequential. If there had been prior damage to his cervical spinal cord it did not interfere with the functioning of his lower limbs whereas neurological deficits were manifest 24 hours after the nail impact, an impact that was well capable of having caused the bulging disc at C3/4 to have compressed the cord through extension or flexion of the neck.
Also with respect to the third point, a 2007 report of an ambulance officer recorded that the plaintiff was ataxic when attended at the scene where he had been assaulted. However Professor Fearnside thought this would be explained by the heavy blow he received to the face at that time, a probable concussive episode and possibly the effects of alcohol. The professor gave evidence that instability of balance can be caused by inner ear disturbance and by disorder of the frontal lobes of the brain or the cerebellum. He could see nothing in the 2007 CT scan by which this ataxia could be attributed to any involvement of the cervical spine at that time.
The medical experts for both parties are in agreement that the 2007 scan does show degenerative changes in the cervical spine already present at that time. Osteophyte formation had by then caused a degree of narrowing of the spinal canal through the cervical vertebrae and the disc bulge at C3/C4 may have been developing then (or at some later date, but before November 2012). Dr Cochrane has taken that evidence, in combination with his view that blood product was in evidence in the spinal cord as at 2007, to form a conclusion that "on balance of probability … it [is] likely that [the plaintiff] had a pre-existing spinal canal stenosis and a proximal cord lesion predating the work-related injury of 9 November 2012". It is the opinion of Professor Fearnside and Dr Winder that a degree of stenosis existed prior to the nail gun incident but that neither it nor anything else had caused spinal cord damage and the plaintiff was neurologically asymptomatic with respect to his cervical spine up to 9 November 2012. For the reasons given above I accept the latter view on the balance of probabilities.

[14]

Plaintiff's post accident lower limb neurological symptoms and treatment

The plaintiff gave evidence that after he was discharged from the Sacred Heart rehabilitation hospital on 21 November 2012 he continued to suffer from poor balance and difficulty with stairs throughout 2013. He said that his balance improved up to mid 2013 but never resolved entirely. He felt unsteady walking uphill or downhill and needed a support or a rail or to hold his partner's hand. He could not run or stand on one leg during 2013. His balance got worse from mid-2013 and from that time he experienced numbness in his thighs. His account of difficulty walking, maintaining balance and climbing up and down stairs, from when he returned home in late November 2012, was corroborated by his then partner who gave evidence that at that time she had to help him with everything except the simplest domestic tasks.
These ongoing disabilities with respect to his lower limbs were also confirmed by records of the St Vincent's Outpatients facility from 13 December 2012, when he attended for assessment and rehabilitation. He then reported that he still felt weak in his legs and he was observed to be unsteady on slopes and uneven ground. He needed to use a rail to go up and down stairs and found it difficult to walk heel to toe. The plaintiff commenced physiotherapy with Dr Schneider from January 2013. Dr Winder saw him on 10 January 2013 and due to concern about the possibility of further damage to the spinal cord recommended a repeat MRI scan in six weeks.
A close friend of the plaintiff, Ms Ching, also confirmed his loss of mobility following the accident and continuing into 2013. She said he made some improvement with respect to balance and control of his legs in the first half of 2013 but from then until he underwent surgery on 25 November 2013 she thought that his balance and leg control declined.
On 12 September 2013 Dr Winder reported to the plaintiff's general practitioner that he remained "mildly hyper reflexive of the upper and lower limbs consistent with his cord contusion injury". Dr Winder considered at that that time that the plaintiff was at high risk of further damage to his spinal cord from the C3/4 disc protrusion and sought approval from the workers compensation insurer for an MRI scan, preliminary to performing anterior cervical discectomy and fusion to decompress the spinal cord. The recommendation for this operation was repeated on 23 October 2013. On 1 November 2013 Dr Winder assessed the plaintiff's symptoms as worsening and warned his GP of the risk of "permanent neurological damage". He sought urgent approval to carry out the surgical procedure he had recommended.
St Luke's Hospital records of observations following the surgery by Dr Winder on 25 November 2013 show that the plaintiff continued to have some ataxia, weakness and poor balance continuing into mid-December 2013. He experienced considerable pain in his neck after the operation, which subsided over about two months. The plaintiff's partner gave evidence that he had considerable difficulty with stairs immediately following his discharge from hospital in December 2013. The plaintiff suffered a complication of the operation, namely, inflammation around the cervical cord in the proximity of the operation site. This gave rise to a spastic gait and ongoing neck pain until the inflammation gradually resolved. Post-operative physiotherapy commenced in mid-January 2014. By then Dr Winder assessed that his strength had greatly improved and there was no evidence of hyperreflexia. However the plaintiff still had some balance difficulty and proprioceptive abnormality. That was manifested by a tendency to fall backwards upon closing his eyes.
By 6 February 2014 Dr Winder found that his walking had significantly improved. On 23 May 2014 the physiotherapist observed that he still had "impaired balance, poor exercise tolerance and neck pain exacerbated by all movements". His active neck movements were grossly limited, consistent with the cervical fusion operation. On examination by Professor Fearnside on 24 November 2014 he had marked ataxia and tandem gait and the Romberg test for proprioceptive abnormality (falling backwards when the eyes are closed) was positive. Dr Buckley, a rehabilitation specialist, confirmed these deficiencies of balance during examination on 1 December 2014.
The plaintiff recommenced attending his gym for rehabilitation exercises in late 2014. He purchased a car during 2014 and has been driving regularly since but only within the Sydney metropolitan area. At examination on 31 August 2015 Dr Cochrane found that the plaintiff's thoracic range of movement was poor and was "compounded by significantly poor balance with the [plaintiff] tending to list or lean rearwards and ipsilaterally when rotating". He would tend to lean towards the side to which he was rotating. Dr Cochrane observed "abysmal tandem gait and in-line balance", with "complete inability to walk on uneven surfaces, stand on raised platforms, elevate or descend ladders or work outside of a neutral position, such as working with an extended neck above head height, leaning forward over a workbench, or having to twist or rotate at a worksite".
The plaintiff gave evidence that he suffered left-sided plantar fasciitis from late 2013 up to the date of the trial. This is an inflammation of the large tendon in the heel. At its most severe it prevented him from running and caused him to limp when walking. Dr Cochrane attributed this to asymmetric gait and the use of a walking stick in the plaintiff's right hand which caused him to favour his left foot. These causes of the plantar fasciitis in turn resulted from the neurological damage occasioned by the accident, which compromised his balance.
The plaintiff said that through 2015 to 2017 his balance improved and the plantar fasciitis affected him less so that his ability to exercise increased. He said that by the time he gave evidence in late 2017 he could walk and run sufficiently to keep fit. He said he is able to walk for an hour a day and to run for three or four minutes. Nevertheless his balance remains to some extent adversely affected.
I understand that the three neurological surgeons and the two specialists in rehabilitative medicine who have examined the plaintiff at various times since 2014, including very shortly before the trial, are in broad agreement that by late 2017 the plaintiff's balance disorder was relatively mild. He also has some degree of diminished proprioception. None of these doctors suggested that he had improved or would improve to a point where he could safely work on a building site. I am satisfied on the balance of probabilities that he is not presently fit to do so and will not be in the future.
The severity of the plaintiff's neurological symptoms in his lower limbs at various times from the date of the accident up to the trial as described above was not significantly in dispute. I accept the evidence which I have summarised in the above paragraphs. There were minor areas of difference between the witnesses concerning a film of the plaintiff exercising at a gym in January 2016. AEA's counsel cross-examined witnesses to the effect that what is shown on this film demonstrates less disability with respect to the plaintiff's balance and lower limb control than what he described in his own evidence and what he exhibited during examinations. In summary the film shows the plaintiff performing various exercises such as skipping, shaking "battle ropes" and swinging a weighted sack from one side of his body to the other. The plaintiff participated vigorously in these exercises over about four minutes and at the conclusion of the film was seen to walk to a motor vehicle and get in it.
Professor Fearnside considered that the plaintiff's actions recorded on this film were inconsistent with his presentation at clinical examination in November 2014 in that the skipping shown on the film is more rapid than he would expect the plaintiff to have been capable of, having regard to the ataxia which the professor had observed. Also, Professor Fearnside did not detect any instability or ataxia in his manner of walking as recorded on the film. However the plaintiff's own evidence is that his balance commenced to improve some time after the operation of 25 November 2013, from about early 2014, and the improvement continued through to late 2017. The variance between what may be seen in the film and what Professor Fearnside had observed in his rooms 14 months earlier appears to be consistent with the plaintiff's evidence of improvement over that time, especially as the professor acknowledged that skipping is one of the rehabilitative exercises recommended for such a patient.
In a report of 5 April 2016 Dr Cochrane assessed that the video footage of January 2016 showed that the plaintiff "has what I would consider entirely normal if not supranormal exercise tolerance, balance and coordination". He thought the balance and coordination demonstrated in the video was "entirely at odds with that demonstrated to me at my assessment of 31 August 2015". Dr Cochrane expressly did not assert that the plaintiff had been embellishing or exaggerating clinical signs during the examination but considered that, if not, he had "improved dramatically" in the four and a half months following 31 August 2015.
As at 5 April 2016 Dr Cochrane thought that in light of the plaintiff's physical capacity demonstrated on the film of January 2016 the deficits earlier observed would no longer be a barrier to him performing workplace physical activities such as referred to at [107] above. However following an updating examination on 30 October 2017 Dr Cochrane reported that the plaintiff still had a "mildly wide-based gait" and that his "foot alignment was normal when performing tandem gait although his balance was poor, and he needed my support to maintain balance". He had "preserved power in the lower limbs". The doctor observed "no overt embellishments or incongruities or inconsistencies evident throughout the assessment". The thoracic range of movement was within normal limits.
Dr Buckley, the rehabilitation expert qualified by the plaintiff, also accepted that the film showed "he's got reasonable and not greatly abnormal balance". This did not cause Dr Buckley to alter his view that the plaintiff is unfit for work on a building site. The doctor pointed out that the activities recorded in the film took place in "basically a static area with highly predictable loads". He accepted that the film showed the plaintiff to be "generally physically fit" but did not think it possible to extrapolate from his ability to work out in the controlled, flat floor environment of the gym to a capacity to work in other environments. AEA's rehabilitative specialist, Professor Jones, also considered it would be unsafe for the plaintiff to work on a building site, notwithstanding his physical capacity shown in the video.
In my view the course of post-accident neurological symptoms in the plaintiff's legs supports the conclusion of Professor Fearnside and Dr Winder on causation. I accept the evidence of Dr Winder that due to a degree of plasticity of the spinal cord (or "spinal cord reserve") this explanation of the cause of the plaintiff's neurological symptoms is not contradicted by the circumstance that those symptoms fluctuated after the event. In the doctor's experience, which he said is supported by extensive literature, after an MRI scan has revealed initial signal change in the spinal cord following insult, there may be improvement of symptoms for a time and then worsening. He said that this phenomenon has been associated with myelomalacia. Dr Winder said there is "no measurable way of predicting" what course the progression of symptoms will follow, which is why he had relatively frequent follow-up consultations with the plaintiff during 2013.
Dr Cochrane's opinion that normally one would see maximum neurological deficit within an hour or two of insult to the spinal cord is not so definitive as to preclude that in this case there may have been cord damage of a kind which led to fluctuating symptoms. It has already been mentioned that Dr Cochrane acknowledged there could be "relatively minor trauma" resulting in "delayed deterioration due to swelling or oedema". Whilst he would expect that neurological symptoms "should" resolve as the swelling resolves he did not suggest this was invariably the case. He said: I suspect there was a degree of temporary trauma involving the cervical cord that was subtle and not picked up and seemingly not associated with any power loss, given the otherwise normal neurological investigations in the approximate 24 hours before the ataxia was recorded. So, given the mechanism of injury, it is reasonable to conclude that there was some trauma and some neurologic consequence from it. What surprises me … is that the delayed … observance … of that ataxia is in my opinion not consistent with a significant trauma and certainly not one that would be evident some five fears later. … But in answer to your question, I can see there must've been at least some degree of spinal cord irritation or injury at the time of the presentation to hospital, given the findings.
In substance Dr Cochrane's opinion on causation of spinal cord injury and consequent neurological symptoms differs from that of Professor Fearnside and Dr Winder only as to the degree of severity of the cord damage occasioned by the nail gun accident. The symptoms, over the course of time, have been proved as per the summary of the evidence which I have given above. I am satisfied that there were no such symptoms prior to the nail gun incident and there is no evidence of any other occasion of spinal cord damage which can be correlated with the observation of neurological deficits from 10 November 2012. Therefore, although the extent and persistence of those deficits in the plaintiff's legs may be beyond the previous experience of Dr Cochrane for a relatively mild impact or irritation of the spinal cord, I am satisfied on the balance of probabilities that the symptoms have resulted from cord damage occasioned when the nail struck the plaintiff in the temple.

[15]

Principles concerning the plaintiff's pre-existing cervical degeneration

AEA contends that because the plaintiff's pre-existing cervical spinal pathology (bulging disc, hypertrophic facet joint capsules and osteophyte growth at C3/4) was advanced and progressive: 1. within one year or at most four years "the chances are" that pathology would have impacted upon his spinal cord in such a way as to "declare itself" by causing neurological symptoms; 2. the "great proportion of the sequelae of the injury to his spinal cord, including the need for operative stabilisation and its consequences would have been suffered by the plaintiff"; 3. those consequences would have included his incapacitation from heavy labouring work and 4. so far as neurological deficits in the plaintiff's legs are concerned, the only consequence of the nail gun accident has been to bring forward the damage to the spinal cord, the symptoms and disabilities and the need for surgery.
I accept the evidence of Dr Winder that the cervical spinal pathology seen on the 2007 CT scan and again visible on the November 2012 radiology (putting aside the increased signal from the cord) was of a degenerative nature and that it is a normal feature of such a condition that it was likely to have progressed from 2007 and would likely have progressed further from November 2012. At least, the broad-based disc protrusion was always likely to expand. Dr Winder said the plaintiff's disc protrusion had already compromised the spinal canal by November 2012 and need only have intruded into that space a further 1 or 2 mm (which he regarded as at least conceivable) for the disc to come in contact with the cord and "cause neurological symptoms and require surgery".
The doctor's evidence also establishes that the osteophytes had grown between 2007 and 2012 and that it is possible they could grow to the point where they would impinge on the cord. Progression of the plaintiff's cervical degeneration, causing either disc or osteophyte contact with the spinal cord, could manifest in neurological deficits and require an operation such as that carried out by Dr Winder in November 2013, even without there being any accident, impact, excessive extension or flexion of the neck or any other form of externally inflicted trauma.
Accepting that evidence as I do, there is introduced into the assessment of the plaintiff's damages the necessity to evaluate a hypothetical situation or circumstance. Had the nail gun incident not occurred: 1. would the degeneration in the plaintiff's cervical spine have progressed as Dr Winder says it was capable of doing; 2. would such progression have caused neurological symptoms, required surgery and left him with residual symptoms (all with substantially the same impact on the plaintiff as what he has in fact experienced commencing from 9 November 2012) and 3. what is the degree of likelihood of all that having occurred?
In Purkess v Crittenden (1965) 114 CLR 164; [1965] HCA 34 Barwick CJ, Kitto and Taylor JJ (referring to Watts v Rake (1960) 108 CLR 158; [1960] HCA 58) said (at 168, emphasis added): It was, in effect, pointed out that it is not enough for the defendant merely to suggest the existence of a progressive pre-existing condition in the plaintiff or a relationship between any such condition and the plaintiff's present incapacity. On the contrary it was stressed that both the pre-existing condition and its future probable effects or its actual relationship to that incapacity must be the subject of evidence (ie either substantive evidence in the defendant's case or evidence extracted by cross-examination in the plaintiff's case) which, if accepted, would establish with some reasonable measure of precision, what the pre-existing condition was and what its future effects, both as to their nature and their future development and progress, were likely to be. That being done, it is for the plaintiff upon the whole of the evidence to satisfy the tribunal of fact of the extent of the injury caused by the defendant's negligence.
The evidence of Dr Winder regarding the plaintiff's pre-accident degenerative condition satisfies AEA's evidentiary burden. The doctor's evidence is reasonably specific and precise as to the pre-existing C3/4 intervertebral joint degeneration, as to the potential future development of that pathology and as to its effects. The issues listed at [122(1)-(2)] are thereby raised. They concern a hypothetical event, namely, the progress of the plaintiff's degenerative disc disease if the accident 9 November 2012 had not occurred. The evaluation of that hypothetical event requires application of principles of assessment explained in Malec v JC Hutton Pty Ltd (1990) 169 CLR 638; [1990] HCA 20 at 643 (Deane, Gaudron and McHugh JJ), as follows: If the law is to take account of future or hypothetical events in assessing damages, it can only do so in terms of the degree of probability of those events occurring. The probability may be very high - 99.9 per cent - or very low - 0.1 per cent. But unless the chance is so low as to be regarded as speculative - say less than 1 per cent - or so high as to be practically certain - say over 99 per cent - the court will take that chance into account in assessing the damages. Where proof is necessarily unattainable, it would be unfair to treat as certain a prediction which has a 51 per cent probability of occurring, but to ignore altogether a prediction which has a 49 per cent probability of occurring. Thus, the court assesses the degree of probability that an event would have occurred, or might occur, and adjusts its award of damages to reflect the degree of probability. The adjustment may increase or decrease the amount of damages otherwise to be awarded. See Mallett v. McMonagle (1970) AC 166, at p 174; Davies v. Taylor (1974) AC 207, at pp 212, 219; McIntosh v. Williams (1979) 2 NSWLR 543, at pp 550-551. The approach is the same whether it is alleged that the event would have occurred before or might occur after the assessment of damages takes place.
In Seltsam Pty Limited v Ghaleb [2005] NSWCA 208 the relationship between earlier High Court authorities and Malec v JC Hutton Pty Ltd was explained as follows (Ipp JA, Mason P agreeing): [104] What was said in Watts v Rake and Purkess v Crittenden now has to be qualified by these principles [in Malec v JC Hutton Pty Ltd] (cf Commonwealth of Australia v Elliott [2004] NSWCA 360 at [81]). Malec has an important bearing, for example, on the way in which a court must determine whether a defendant has discharged the "disentangling" evidentiary burden on it of showing that part of the plaintiff's condition was traceable to causes other than the accident and that, had there been no accident, the plaintiff would have suffered disability from his pre-existing condition. [105] Where a defendant alleges that the plaintiff suffered from a pre-existing condition, the evidential onus as explained in Watts v Rake and Purkess v Crittenden remains on the defendant and must be discharged by it. Nevertheless, to the extent that the issues involve hypothetical situations of the past, future effects of physical injury or degeneration, and the chance of future or hypothetical events occurring, the exercise of "disentanglement" discussed in those cases is more easily achieved. That is because the court is required to evaluate possibilities in these situations - not proof on a balance of probabilities.
The application of Malec v JC Hutton Pty Ltd to assessment of the likely progression of a pre-existing condition was again recognised in Metro North Hospital and Health Service v Pierce [2018] NSWCA 11 at [113]-[114] (White JA, Macfarlan and Payne JJA agreeing). The principles bear upon the assessment of all such components of the plaintiff's damages as may be affected by taking into account the possibility that he would have suffered neurological damage and required neurosurgery even if he had not been injured by the explosive powered nail in November 2012. The assessment of his future economic loss is one component affected by this possibility. Future economic loss is to be assessed in accordance with s 13 of the Civil Liability Act. The requirement of subs (2) that the court should have reference to "the percentage possibility that the events might have occurred but for the injury" is to the same substantive effect as the principle laid down in Malec v JC Hutton Pty Ltd. Section 13 is as follows: 13 Future economic loss - claimant's prospects and adjustments (1) A court cannot make an award of damages for future economic loss unless the claimant first satisfies the court that the assumptions about future earning capacity or other events on which the award is to be based accord with the claimant's most likely future circumstances but for the injury. (2) When a court determines the amount of any such award of damages for future economic loss it is required to adjust the amount of damages for future economic loss that would have been sustained on those assumptions by reference to the percentage possibility that the events might have occurred but for the injury. (3) If the court makes an award for future economic loss, it is required to state the assumptions on which the award was based and the relevant percentage by which damages were adjusted.
For reasons appearing below I assess the likelihood that the plaintiff's disc degeneration would have caused symptoms and required an operation even if there had been no accident in November 2012 as not such a high likelihood that it should be regarded as practically certain. Nor do I regard it as such a low chance as to be speculative. Hence, I should quantify the degree of likelihood (the issue at 122) in accordance with Malec v JC Hutton Pty Ltd, if it is possible to do so.

[17]

Professor Fearnside

Professor Fearnside was asked about the broad-based disc bulge at C3/4 as reported from the MRI scan of the plaintiff carried out on 13 November 2012. The bulge protruded rearward toward the spinal canal over a wide section of the disc base causing moderate central canal stenosis. Professor Fearnside agreed that this protrusion would have predated the scan (and hence the accident) by at least many months, in his view by years. He considered that the other degenerative changes picked up by the scan (facet joint hypertrophy and osteophyte formation) must also have been "there and developing for a long time".
Professor Fearnside said that such a degenerative spinal condition is usually stable but can progress. He was not asked to express the degree of likelihood of progression, to any particular stage, any more precisely than that, either for the plaintiff or for patients with this disorder in general. Professor Fearnside said that with a disc at C3/4 bulging to the degree shown in the MRI of 13 November 2012, the plaintiff would have been at increased risk of suffering "serious cervical pathology" from various types of trauma to which he would be exposed in the ordinary course of his life. For example, the doctor agreed that if the plaintiff was dumped by a wave while body surfing or suffered sudden movement of his head in a rear end vehicle collision or made heavy contact in a game of rugby league, this could occur.
By agreeing that such events could cause "serious cervical pathology" I take Professor Fearnside to be referring to contact of the disc with the spinal cord similar to what, as I have found, occurred as a result of the nail gun injury. The doctor agreed that heavy physical labouring work can also bring about such a result. From the other answers given I infer that this could occur, for example, if the plaintiff accidentally knocked his head severely against an overhead beam or inadvertently was struck in the head by materials being carried by another workman. Unsurprisingly the doctor did not purport to offer any estimate of the degree of likelihood of any of these things occurring but the effect of his evidence is that relatively minor impacts, such as might be considered not uncommon in the life of an active young man engaged in physical work and leisure activities, would be capable of causing damage to his spinal cord because of the increased vulnerability created by the compromised central canal at C3/4.

[18]

Dr Winder

I have already referred briefly to Dr Winder's view of the progressive nature of the plaintiff's disc degeneration at C3/4 (see [120]-[121]). The doctor said that, having regard to the progression of the disc bulge evident from comparison of the radiology from 2007 with that from November 2012, he was at a higher risk of suffering spinal cord damage from relatively minor head impact than a person who did not have such developed canal stenosis. Without such external impact Dr Winder did not think it likely that pressure on the spinal cord, sufficient to require cervical surgery, would have occurred just as a result of progression of the disc bulge or osteophyte formation. He said: Is it likely? No, we've got plenty of asymptomatic patients who have cervical canal stenosis who do not require surgery.
However the doctor acknowledged that development of the bulge to the point of requiring surgery, even without external impact, was possible. He gave these answers: Q What about if that disc bulge progressed, and made the stenosis more severe? A The only way that would be picked up is if he got a neurological complication, and if it absolutely caused one then he would be getting surgery, that would be our recommendation. Q Could that occur that this could continue to bulge and extrude into the space, and start to impact just by squeezing on the cord, as opposed to being jolted against it? A Absolutely, it is possible, and that's a normal part of degenerative change with a broad based disc protrusion that it can expand, and if it already has a compromised canal, it only needs to compromise it by potentially 1 or 2 millimetres over a lifetime, that is possible that could cause neurological problems and require surgery Q What about the growth of the osteophytes? A That's unknown. They can grow, and his clearly have, comparing the 2 scans, but then it cannot get any worse. Some do get worse, we see cases where the osteophytes have increased significantly, requiring further surgery. Q So they may grow to the point where they are growing against the cord? A Yes. Q What are the factors? A We don't know. … Q … in terms of quantifying the risk [of] him coming to surgery just purely for degenerative changes, is that something you can do? A I don't think you can. To my knowledge, there is no longitudinal study which has done comparisons [from] single level narrowing of the spinal canal to say whether you are likely to have surgery.
Dr Winder stated that a significant proportion, 70%, of patients seen in his clinic with disc protrusions have woken up from sleep with symptoms. That is, such protrusions can commence to cause neurological symptoms in people who are sedentary and for whom no antecedent event has been causative.

[19]

Dr Cochrane

In Dr Cochrane's report of 6 June 2016 he said: … Mr Wharekawa was at risk of suffering a neurological deficit related to the cervical spine pathology at any time with any incident that may have resulted in, for example, hyperflexion, hyperextension of his neck, a fall, or axial loading to the cervical spine. … … I think it likely that Mr Wharekawa was at risk of developing lower limb pathology from cervical spinal cord compression due to what I believe to be significant pre-existing pathology at the C3/4 level. … I think it possible that with or without the nail gun injury Mr Wharekawa may have developed significant cervical spinal cord pathology in his lifetime and might have the likely pre-existing degenerative problems and effacement of the cervical cord at C3/4.
In oral evidence Dr Cochrane said that, by reason of the broad-based disc bulge at C3/4 which was present before the nail gun injury, the plaintiff's "reduced calibre spinal canal and a degree of compression on the spinal cord" was such that "even a relatively minor trauma could result in a significant neurological deficit in the future". As examples of the kind of minor trauma which would be sufficient, he referred to axial loading on the spine by the plaintiff falling on his head (for example, "diving in and hitting a sand bar") or by a weight dropping on his head or shoulders. Alternatively spinal cord injury could be caused by "whiplash injury in a car" or by tucking his head in upon falling to the ground. Dr Cochrane thought that if the plaintiff stood up and bumped his head on solid material above him on a building site, for example, contact of the disc with the spine and consequent cord damage could result.
Dr Cochrane said there was no clinical or research data which would enable him to quantify the degree of risk that an existing bulge to a C3/4 disc would come in contact with the spinal cord and cause neurological symptoms. However, anecdotally based on his clinical experience, he considers that spinal cord injury of this nature would be 5 to 10 times more likely in a person with a pre-existing disc bulge than in a person with no such pre-accident pathology. It is also his clinical experience that spontaneous disc protrusion in patients with degenerative disc conditions like that of the plaintiff is relatively common, occurring in one third to one half of patients presenting with neurological symptoms. He regards patients with broad-based long-standing disc protrusions such as the plaintiff's as at higher risk of a spontaneous pathological event than patients without such disc degeneration.
Dr Cochrane also gave evidence that "all degenerative processes, almost without exception, will progress over time". He included in this the process of degeneration of intervertebral discs, such as exhibited by the plaintiff in the MRI of 13 November 2013. The doctor said that even minor or repetitive trauma would accelerate such degeneration, including that of the facet joints and the osteophyte growth, and "the more vicious the trauma the more rapid the acceleration". Thus it is his view that the plaintiff's disc degeneration at C3/4 could have progressed through time, possibly with acceleration through minor impacts, to the point where contact with the spinal cord and neurological symptoms would result.

[20]

Conclusion

As mentioned at the outset of these reasons, the plaintiff was 28 years old at the date of the accident. He acknowledged that he had not done well at school and that limitations with respect to formal learning had contributed to him not completing an apprenticeship as a mechanic. He was fit and strong and was a capable labourer. Labouring was work that suited his abilities. He liked the work and chose it because it occupied him outdoors. The plaintiff was reliable and was valued by his employer. I am comfortably satisfied that he would have continued as a builder's labourer for most of the remainder of his working life had this accident not occurred. He might have progressed to greater responsibility on building sites but the physical aspects of his work would have remained the same.
The plaintiff planned to seek work in Western Australian mines or Queensland, possibly in 2013. If he had been successful in that, it is still likely that he would eventually have returned to city living, in view of his social ties to Sydney, and it is likely that he would then have returned to labouring in the building trade. Having regard to the narrow range of the plaintiff's skills it is likely that any work he obtained in the mining industry would have been in a labouring capacity. It follows that throughout his working life the plaintiff would always have been exposed to the risk of aggravating the degeneration of his C3/4 disc, perhaps acutely, through heavy manual exertion and exposure to accidental knocks. His risk of accelerating the degeneration would have been higher than for a person in a sedentary occupation.
The plaintiff had played rugby and skied and enjoyed rollerblading when he was younger. By the time of the accident he had moved on from all of those activities. He continued to enjoy swimming, body surfing and boogie boarding. These activities in the surf would have exposed him to risk of damage to his spinal cord by a mechanism similar to that of the nail gun accident. The plaintiff had been involved in physical altercations at licensed hotels in the past but the evidence does not suggest that at the date of the accident he continued to frequent such places at times or in circumstances which would have heightened the risk of him being hit in a manner which might cause contact with his spinal cord by the bulging disc.
I consider it highly likely the plaintiff's prolapsed disc would sooner or later have contacted his spinal cord, with consequences much the same as those which he experienced after 9 November 2012, including surgery. It is not possible to say when. He might have continued, for example, for, 12 years or 22 years, to age 40 or 50, with no such event. In a case such as the present where the hypothetical fact involves both the occurrence of an event and the number of years which will elapse before it occurs (if it does), it is not practical to apply a percentage-chance approach to achieve a strictly mathematical discount of damages. Isolating the degree of likelihood of an occurrence without the date when it will come to pass is not meaningful.

[21]

Manner of allowing for the risk of spinal cord damage in any event

To account for these circumstances in awarding damages for non-economic loss, I will (a) determine what percentage of a most extreme case is presented by the plaintiff's disabilities and suffering, on the basis that the neurological deficits for the whole of the balance of his life expectancy are attributable to the accident and (b) make a deduction from that percentage in recognition that there is a high probability he would at some time have commenced to suffer neurological symptoms and had to endure the surgery, even if the accident had not occurred. By that means I will attempt to quantify the proportion of a most extreme case which, in the plaintiff, has been caused by the accident.
In calculating future economic loss I consider that a discount to allow for the vicissitudes of life must be applied at a higher level than the usual 15%, to take account of my findings regarding the likelihood that neurological symptoms and a need for surgery would have arisen in any event. For reasons explained below, I find that the plaintiff's post-traumatic migraine syndrome has rendered him incapable of earning a living within the limits of his pre-accident aptitudes, independently of the impact of his neurological symptoms upon earning capacity. I do not consider that there is any significant degree of likelihood that he would have suffered this migraine condition if the accident had not occurred.
However the vulnerability to spinal cord damage has at all material times been of such a high order that, irrespective of this accident, it would likely have disrupted his working life at some time (with neurological symptoms, surgery and recovery) and thereafter narrowed the range of work he could do. For a man of his limited abilities such narrowing would make it hard for him to obtain continuous employment once he became unfit for heavy labouring. It would be unrealistic to assess the plaintiff's diminished earning capacity as if, but for the accident and the migraines, he would have worked full-time as a leading hand builder's labourer continuously to age 67.

[22]

Post-accident development of migraine

The plaintiff gave evidence that prior to the accident he experienced headaches only a few times a year, up to about 2010. The history he gave to Dr Tisch, his treating neurologist, as recorded in the doctor's report of 7 February 2014 is that he had suffered migraines "since his 20s which have occurred 1 or 2 times per year lasting up to 4 days". I regard the history given to Dr Tisch as the more reliable account. The plaintiff said his headaches prior to the accident in November 2012 were not as frequent nor as severe as those he suffered afterwards. He said prior to the accident they "did not stop me from working or interrupt me with my daily life".
The St Vincent's Hospital clinical notes record that the plaintiff complained almost continuously of headache from the day after the accident. He was prescribed Panadeine Forte and other analgesic medications throughout his hospital stay. After discharge on 6 December 2012 he continued to use Panadeine Forte to combat headaches about twice per week. He said that during the first half of 2013 his headaches "got better" but did not completely resolve. Their frequency fluctuated such that at times he experienced them "a few times a week", at other times "every single day".
When the plaintiff was later seen by Dr Tisch, his post-accident migraine was described by the doctor in these terms: Following the nail gun injury, Ray experienced almost daily migraines for the first few weeks. These were characterised by severe, constant, bifrontal headache associated with sonophobia, phonophobia, disequilibrium and imbalance. He would lie down in a darkened room. The headaches would last 6 hours, sometimes up to 24 to 48 hours. … The migraines gradually reduced in frequency over the following months … .
At some time during 2013 the plaintiff's then partner, Ms Jansen, observed that he suffered headaches which would cause him to be "writhing in pain until the painkillers he had taken kicked in. He was visibly and physically distressed as a result". When the plaintiff was reviewed by Dr Winder on 12 September 2013 he reported that he had "ongoing headaches which are occurring every three to four days, which he has been trying to manage with Panadeine". Dr Winder considered that mere management of the symptoms with analgesics was inappropriate.
Following the surgery of 25 November 2013 it appears the migraines worsened. On 6 February 2014 Dr Winder reported to the plaintiff's general practitioner as follows: He has unfortunately been debilitated by almost daily migraines for which he is having to lay down with the lights turned off in a darkened room because of the hypersensitivity of his eyes. This may well be a direct response secondary to his surgery which we can occasionally see and I feel he needs to be reviewed relatively urgently by a neurologist […] .
At this point the plaintiff was referred to Dr Tisch on an urgent basis because of the severity of the migraines. Upon review on either 6 or 7 February 2014 Dr Tisch reported that the migraines: have become more frequent again following spinal surgery in November and particularly severe since January 2014. They are now occurring daily and he describes them as migraines on steroids. Many occur after waking from sleep, some are onset during the day.
Dr Tisch diagnosed "severe chronic migraine with analgesic rebound". He recommended progressive reduction of the intake of Panadeine and he prescribed a migraine preventative medication. The doctor warned the plaintiff "that his headaches will get worse before they get better as the inevitable consequence of reducing Panadeine Forte and overcoming the analgesic rebound".
Upon Dr Tisch reviewing the plaintiff two months later the plaintiff reported that he had had 20 migraines in the previous 28 days and had suffered abdominal cramps and loss of appetite as a side-effect of the preventative medication. The prescription was changed. At that stage, on 4 March 2014, Dr Tisch reported: Given that he has failed one of the best anti-migraine agents … I am doubtful that oral medications will achieve satisfactory control and Botulinim Toxin injections are more likely to be effective.
These injections are commonly referred to as "Botox". Their therapeutic effect was explained by Dr Tisch as relaxing targeted muscles, distributed over the scalp and posterior neck. He said the injections are also thought to deplete "certain pain mediating substances" and that although their efficacy is well established the physiological basis of their operation is "incompletely understood".
Four months later again, in mid-July 2014, the plaintiff reported he was "still experiencing severe migraines weekly as well as chronic daily headaches". A Botox injection was then administered and he received from it "good improvement in migraine control" but only for three to four weeks. Thereafter, migraines recurred two or three times per week. Further injections, apparently of a higher dose, were given in mid-September and early December 2014. The beneficial effects of the latter injection lasted until about the end of January 2015. Since then he has had regular injections every three to four months.
At the trial Dr Tisch gave this prognosis for the post-traumatic migraine syndrome which he diagnosed: I think it's now sufficiently persistent that I think it's unlikely that it will remit. Several years have elapsed since the post-traumatic migraine syndrome started and he is still needing the Botox injections every three to four months like clockwork, and we know that because his migraines intensify as the Botox wears off at the end of the treatment cycle. So, as the treating doctor, I cannot in any way feel comfortable withdrawing the Botox treatment and his condition is behaving in a permanent manner. I think the probability of it going away by itself in the future is quite low, even remote.
The doctor gave the opinion that "he will suffer this for the rest of his life and he will need the Botox". Based upon his experience of the plaintiff responding to the treatment to date, he considers him likely to continue to respond.
I accept the evidence summarised above regarding the onset and course of the plaintiff's migraine symptoms, the treatment he has received and which he is continuing to receive. I accept Dr Tisch's diagnosis and his prognosis. In the evidence of the plaintiff and of some of his lay witnesses there was a degree of variance in the description of past symptoms and their frequency. The evidence which I have summarised above and accepted is largely supported by contemporaneous medical records of histories given by the plaintiff at relevant times. Dr Tisch's diagnosis was not the subject of any contrary medical opinion. There was no challenge to his evidence about the necessity for the treatment he has administered or to the doctor's prognosis.
I accept the plaintiff's evidence regarding his migraine symptoms as at the date of the trial. He said a migraine attack "can happen … at any time". Sometimes he would have five or ten minutes' warning of an attack. At other times an attack can come on "right away". Sometimes he has such attacks every day for a few days or even up to two weeks, then he may have no further attack for "like a few days up to like - a few weeks … it's all over the place". After the Botox injections he is still not completely free from attacks and may suffer one or two per week for durations of between four hours and two days.
Ms Ching gave evidence, which I also accept, of the severe effect these migraine attacks have upon the plaintiff. She has observed him exhibit signs of extreme disabling pain when suffering a migraine. On one occasion she observed the commencement of an attack whilst the plaintiff was driving and he "barely made it back to his flat in Bondi because of the pain". To Ms Ching's observation the plaintiff deals with these attacks by taking prescribed medication which puts him heavily to sleep.
Even allowing for the inherent element of approximation in this evidence regarding rapidity of onset, frequency, duration and severity of migraines, it is apparent that the optimal treatment he is receiving from Dr Tisch still leaves the plaintiff with a chronic condition which seriously detracts from the quality of his life and greatly limits his capacity for gainful employment. The plaintiff has himself correctly observed that the unpredictability of onset and duration of the attacks would make him unreliable to an employer.

[23]

Cause of post-accident migraine

In Dr Tisch's opinion the migrainous headaches which the plaintiff has suffered from the day after the nail gun accident have been caused by that event. The doctor considers that the history of symptoms related above "is entirely consistent with a severe and persistent post-traumatic headaches [sic] migraine syndrome and whiplash". On the history given to him by the plaintiff Dr Tisch assessed that prior to the accident he had "occasional migraine, or shall we say, a susceptibility for migraine". In the doctor's experience when such a person suffers a blow to the head of the type that occurred here "the likely scenario is that the headache that they will develop in consequence to that will be more in keeping with migraine than an ordinary headache, because they are migraine susceptible".
In answer to my own questions the doctor said that he thought the mechanism of injury to the plaintiff's spinal cord was that the "bat-like violent blow and subsequent jolting and whiplash type injury to his neck" caused some part of the disc at C3/4 or some other part of the spinal structure to press against the spinal cord. He then gave these answers: Q From that to the symptoms of migraine, is the causal link fully understood in your specialty? A I think we need to be careful in attributing the migraine process entirely to the neck. Let's not forget that he also was impacted severely in the head and I think it's a combined thing. I think the local trauma to his head was also a significant driver for the development of post-traumatic migraine. Q Is that causal connection fully understood in your specialty? A It's well-described and there is abundant literature that after a head injury - and it does not need to be a head injury with loss of consciousness … even mild to moderate head injuries can be associated with post-traumatic headaches, the majority of which take the form of migraine, so called post-traumatic migraine, and that's indeed what I think he is suffering from.
Dr Tisch does not consider the fact that the headaches were not constant for the whole period following the accident up to the date of his surgery in November 2013 inconsistent with the attribution of this migraine condition to the nail gun accident. He said that the history is: very typical in post-traumatic headache and migraine. It's a fluctuating disorder with periods of exacerbation as well as periods of relative remission.
Dr Tisch took into account that venous engorgement following the operation of November 2013 caused some pressure in the cervical spinal cord and led to symptoms of spastic gait and discomfort. He took into account that the plaintiff experienced more frequent migraines following the operation. This did not alter the doctor's view of causation. He said: the post-traumatic headache and migraine syndrome was already well-established prior to his decompressive surgery and was the result of the nail gun injury, not the surgery.
Dr Tisch did not consider that the syndrome would have arisen from the degenerative spondylosis at C3/4 as seen in the MRI of 13 November 2012. He was asked whether, having regard to that degeneration, he would have expected the plaintiff to suffer the migraine condition "without the intervention of a specific injury of that type" (referring to the nail hitting the left side of the plaintiff's head, with a force as if he had been hit by a bat and causing him to stagger to the right). The doctor said: No. I think he wouldn't have developed this post-traumatic migraine syndrome at all had he not been hit in the head with the nail.
Dr Tisch considers that although the surgery may have caused the plaintiff additional headaches: normally if someone is getting headaches after a spinal decompression they are usually self-limiting and disappear within a week or two, maybe a few weeks, they don't persist for months and years as we've seen.
If the plaintiff had not suffered the nail gun injury, Dr Tisch would not have expected the spinal fusion operation in itself to cause permanent migraines of the type the plaintiff has suffered and continues to suffer. The doctor has never seen such a consequence of surgery in his clinical experience. He accepted that the operation had a detrimental effect upon control of the post-traumatic headache and migraine syndrome, which the plaintiff had suffered since the accident one year before. The doctor considers the syndrome was susceptible to worsening from the surgical intervention.
I accept that the plaintiff's chronic and established post-traumatic migraine and headache syndrome was caused by the nail gun accident. No contrary view was expressed by any other witness with comparable expertise. Dr Tisch adhered to and justified his opinions most convincingly in cross-examination.

[24]

Psychiatric consequences of the accident

Two psychiatrists who have examined the plaintiff, Dr Jungfer (who was engaged by the plaintiff's solicitors) and Dr Selwyn Smith (engaged by AEA) have diagnosed him as suffering post-traumatic stress disorder ("PTSD") which they consider was caused by his experience of the nail gun incident. On the basis of the history taken by Dr Jungfer she said the disorder is characterised by intrusive recollections of the circumstances in which the plaintiff was injured, nightmares and a highly anxious reaction whenever he is exposed to a construction site environment.
After a second examination of the plaintiff on 25 May 2017 Dr Jungfer concluded that the plaintiff's PTSD symptoms persisted but had stabilised. She did not think any further "psychological intervention" was indicated. Dr Smith's diagnosis is PTSD "in partial remission". Dr Jungfer recorded that in May 2017 the plaintiff described ongoing feelings of low self-esteem and episodic depression and anxiety. She regards these symptoms as being caused by the PTSD. Dr Smith did not receive from the plaintiff any report of having experienced depressive symptoms. In view of the plaintiff's history of neurological symptoms following the accident, his experience of the surgery and recovery, his ongoing battle with episodes of migraine and his inability to return to the physical work to which he was so well suited, I accept that he does, at least from time to time, suffer low mood, loss of self-esteem and frustration with his situation. It would be very surprising if he did not.
The plaintiff reported to Dr Jungfer that since the accident his memory has become worse, his thinking has slowed and a pre-existing stutter has been exacerbated. Dr Smith was not told by the plaintiff that he had any cognitive impairment. There is disagreement between the psychiatrists as to whether heightened anxiety associated with the PTSD may be causing his stutter to worsen. I do not consider that these discrepancies in the evidence are capable of being resolved in the absence of some objective measure of cognitive ability and of speech impediment, before and after the accident. But I also do not think that this is important to the assessment of damages. The manner in which the plaintiff was able to give evidence on my assessment showed an ability to respond to questions, to express himself and to articulate reasonably, consistent with his admittedly modest level of education. His hesitancy of speech requires a degree of patience on the part of the listener. For the purposes of assessing damages, even if his stutter is somewhat worse than before it is not a significant disability and is not materially disabling with respect to his capacity for employment.
Most importantly for the purposes of assessing damages, both psychiatrists are of the view that his reaction to building site environments, which is a manifestation of his PTSD, disables him from returning to work as a builder's labourer. However they both consider that the PTSD does not otherwise prevent him from working.

[25]

Non-economic loss

In determining the severity of the plaintiff's non-economic loss as a percentage of the most extreme case for the purposes of s 16 of the Civil Liability Act, I take into account the following factors: 1. The plaintiff suffered very considerable and distressing shock and local pain to the head and neck upon the impact of the nail and during the first days of recovery in hospital. 2. He has been affected by loss of balance, fluctuating during the first 12 months until his spinal fusion operation and gradually improving thereafter, culminating in a residual degradation of balance which will remain with him. 3. The plaintiff has had to undergo spinal surgery, including the complication of the operation through engorgement of the cord and attendant neurological deficits. 4. The plaintiff has suffered severe recurrent migraines which greatly interfere with his enjoyment of life. He will continue to suffer them indefinitely and will always require injections, approximately every 12 weeks, to reduce their severity as far as possible. 5. The plaintiff has suffered and will continue to suffer PTSD but not in a severely intrusive or debilitating form. He has suffered and will likely continue to suffer episodic depressed mood and frustration as a result of the limitations upon his physical capacities. 6. The plaintiff is now aged 33 years and has a life expectancy in the order of a further 50 years. 7. Allowing for the high degree of likelihood that the plaintiff would have suffered such symptoms and had to undergo such surgery at some stage of his life, nevertheless there is to be taken into account a reasonable chance that without the accident he may have had another ten or more of his younger and more active years free of such pain and suffering and a small chance that he would have escaped this altogether.
Assessing the plaintiff on the basis that all of his neurological symptoms as well as the migraines and PTSD, for the remainder of his life, are wholly attributable to the accident, I would find him to be 45% of a most extreme case. Making allowance for the likelihood of spinal cord damage in any event, as referred to at [142] and [173(7)], I would reduce the percentage of a most extreme case that has been caused by this accident to 35%. Applying that percentage to the statutory maximum amount of $612,500, the non-economic loss component of the plaintiff's damages is $214,375, which is to be rounded to $214,500 (see Civil Liability Act, s 16(4)).

[26]

Past economic loss and superannuation

I find that from the date of the accident up until trial the plaintiff has been entirely incapacitated from working in any role reasonably open to him, as a result of the combined effect of the neurological symptoms affecting his legs, the migraine attacks and PTSD. This finding is qualified to the extent that since about late 2014 he has been able to perform minimal casual work on the reception desk at the gymnasium where he trains, for which he has been remunerated with the value of a free gym membership and nominal payment. That work was initially on one day per week, for $30. At some date before 30 April 2016 (the date of Ms Vucovic's statement) he commenced to help on the gym reception desk two days per week, at $55 for 5½ hours. The work has been to a degree intermittent due to unpredictable disabling migraine attacks.
The incapacity from work throughout this period has been due in part to the plaintiff's poor balance as a result of neurological damage. This has precluded him from working on building sites. The PTSD and his inability to do heavy lifting because of the risk of further damage to his cervical spine have also precluded him from such work. I accept that for some of the period up to trial the plaintiff would have been physically capable of other unskilled work such as that of a storeman, a kitchen hand, a courier or driver (provided no heavy lifting were required). Those are occupations for which Dr Buckley, a rehabilitation physician, considered him physically fit as at the date of the trial. However the severity and unpredictability of his migraines in my view has disqualified him from such employment to date.
After assessing the plaintiff on two dates during the pre-trial period, Dr Buckley expressed the view that he was unemployable on the open market. He attributed this to the plaintiff's limited education, modest intellectual capacity and lack of skills or the capacity to acquire them, combined with residual balance deficits, constraints upon heavy lifting, PTSD and intermittently disabling migraines. I accept Dr Buckley's assessment.
The plaintiff was a permanent casual employee earning $846 net per week at the date of the accident. He would have worked only 48 weeks per year and, as a casual, would not have been entitled to holiday pay during the usual four week shutdown of the building industry from late December into January each year. It is reasonable to infer that he would have taken four weeks' holiday per annum. AEA submits that past economic loss should be calculated on the basis that he would have worked only 47 in each year, losing one week to sickness or other reasons for absence without pay. There is no evidence to justify a finding that he would have lost an additional week in every year for the past five, for such reasons.
Mr Weatherall, the principal of the plaintiff's former employer, gave evidence that by the date of his statement, 29 April 2016, the plaintiff would have been a leading hand earning $1,042 net per week if he had not suffered the accident. There is no evidence about increases in rates of pay over the relevant period in the building industry generally. Taking into account increases in the cost of living and the employer's favourable view of the plaintiff and desire to retain and promote him I infer that it is more likely than not he would have received annualised increases of about 2%.
There must be allowance for his receipt of an average of approximately $40 per week from the gym since late 2014. Accordingly I calculate his loss of earnings up to the date of the trial as follows: Period Number of weeks Rate $ Extension $ 10.11.2012 to 9.11.2013 48 846 40,608 10.11.2013 to 9.11.2014 48 863 41,424 10.11.2014 to 9.11.2015 48 840 40,320 10.11.2015 to 29.04.2016 20 858 17,160 30.04.2016 to 29.04.2017 48 1,002 48,096 29.04.2017 to trial 26 1,023 26,598 Total $214,206

[28]

Future economic loss

Mr Weatherall said he could not re-employ the plaintiff even if his balance and strength were not compromised, because of the unreliability of his attendance due to the post-traumatic migraine syndrome. Ms Vucovic, who has given him the part-time employment at the gym she operates, does not regard the plaintiff as employable in her type of business on a full-time basis, at least in part due to his inability, at short notice, to attend work when he suffers a migraine attack. She has experienced his unreliability in this respect but makes allowance out of friendship and a desire to help the plaintiff. AEA submits that Ms Vucovic's evidence demonstrates only "modest" unreliability as a result of the plaintiff's migraine attacks. I do not accept that as a meaningful characterisation of her evidence. In any event the degree of unreliability the witness was able to describe is qualified by the circumstance that she has only ever sought the plaintiff's services at the gym reception desk for part of one or two days per week. His unreliability to an employer requiring him to work five or six days per week would be a problem of an entirely different order.
AEA also submits that the plaintiff's employability should not be found diminished by reason of the migraines in the absence of an opinion from Dr Tisch to that effect. I reject that submission. The Court is able to make its own assessment of whether or not frequent and unpredictable absence due to migraine, for one or multiple days on each occasion, would affect adversely the plaintiff's prospects in the market for unskilled labour. I conclude that this characteristic of the plaintiff would make it impossible, in practical terms, for him to obtain regular full-time employment within the limited range of jobs for which he is suited.
The plaintiff contends that but for the accident he would most likely have worked to 67 years of age and that his future economic loss should be calculated on the basis of 34 years of earnings at the rate of $1,063 per week. The rate is based on the evidence referred to at [179]. AEA submits it is far more likely that he would only have worked in the building industry as a leading hard builder's labourer until, at most, age 60. That is, he should be regarded as having lost no more than 27 years of earnings. I accept AEA's submission but I consider the resulting calculation should be subject to further adjustments.
First, there should be a discount to allow for the quite high likelihood that at some point during those 27 years the plaintiff would have been unable to earn at all for 18 to 24 months, as a result of a cervical spinal incident and the need for an operation. Secondly, there must be a reduction for the risk that, in such an event, the plaintiff's subsequent employability would be restricted (even in the absence of the migraines and PTSD) and that he would suffer reduced average earnings. As referred to at [144], narrowing of the range of work he could do, to exclude heavy labouring, would make it difficult for him to sustain full-time employment. Thirdly, an allowance in the plaintiff's favour should be made for the reasonable likelihood that, if he had ceased to work as a labourer in the building industry after 27 years at age 60, he nevertheless would have been able to continue working in some less heavily physical capacity had he not been afflicted with the migraines and PTSD.
The third of the above adjusting factors offsets the first two to some extent. As a best estimate I take these three considerations into account by increasing the allowance for the vicissitudes of life from 15% to 20%. I regard his residual earning capacity as currently $55 per week, taking into account the casual/part-time work at the gym. I see no reason why he should not be able to sustain at least that modest level of earnings. The employment through which he derives it at present is to some degree charitable but it is reasonable to predict that another equivalent part time job could be obtained if the present one should end. The lost wages are therefore $1,063 less $55, leaving $1,008 per week. The net present value of $1,008 per week for 27 years at a discount rate of 5%, after making the 20% deduction, is $631,411 (this and all subsequent figures are rounded to the nearest whole dollar).
Compulsory employer contributions under the Superannuation Guarantee (Administration) Act will increase to 12% by 1 July 2025, with 0.5% increments at various dates between now and then. I apply to the net present value of lost net wages the weighted average percentage for 27 years, in accordance with the table given by Mr D Villa, Annotated Civil Liability Act 2002 (NSW), 3rd Ed, Lawbook Co, Sydney, 2018 at [2.15C.050], namely, 13.9%. The amount for future superannuation contributions at 13.9% is $87,766.
I reject AEA's submission that damages for future economic loss ought to be awarded in the form of a mere "buffer" of between $75,000 and $250,000. That proposition is advanced upon the basis that the plaintiff's migraines have not been shown to compromise his earning capacity into the future and that he would most likely suffer damage to his cervical spinal cord within 1 to 4 years. For reasons given above I find that the ongoing migraine condition, being entirely attributable to the accident and not something from which there is any significant likelihood the plaintiff would have suffered otherwise, has substantially destroyed the earning capacity of this workman, vulnerable as he was by reason of his lack of breadth in work capabilities. I do not accept that the evidence of the medical specialists justifies a conclusion, to any degree of confidence or percentage chance, that he would in any event have sustained neurological damage within four years. If driven to apply a percentage chance estimate for such a short time frame I could not put it as more than 5%.

[29]

Past domestic care

The plaintiff advanced a claim for past domestic care, provided to him by his former partner Ms Jansen until the end of their relationship in February 2015. The period between 9 November 2012 and February 2015 has been broken up into stages, including periods when the plaintiff was hospitalised, and varying numbers of hours per week of assistance have been claimed for the respective stages.
I do not accept that any number of hours should be allowed for periods when the plaintiff was hospitalised. I have no doubt that Ms Jansen would have visited the plaintiff at those times and been attentive to him but I do not consider that there would have been "a reasonable need" for gratuitous care from her (within the meaning of s 15(2)(a) of the Civil Liability Act). The plaintiff was cared for in renowned hospitals on each occasion and there is no evidence that the nursing care had to be supplemented.
Ms Jansen gave evidence of the care she provided for the plaintiff when he was discharged from hospital in November 2012, from then until he was admitted for the spinal operation one year later, and again following his discharge and rehabilitation after that operation. The plaintiff and Ms Ching also described the nature and extent of care provided by Ms Jansen. His needs varied over the period from late November 2012 to about mid-2014. At times he needed assistance walking, particularly on slopes. He was unable to fulfil his share of household duties and Ms Jansen took up the shortfall. It was necessary for her to assist him with showering, dressing and other aspects of self-care during some periods when his balance was particularly poor. During periods when he suffered from severe migraine attacks everything about his self-care had to be done for him.
Estimates of how many hours this gratuitous domestic care may have required have been provided in elaborate reports by experts. Ms Jansen worked full-time as a schoolteacher during the relevant period and supplemented her income with weekend work at a hotel. The plaintiff's disabilities throughout the relevant period called for assistance which is well described in the evidence, in general terms. For this the Court can make an estimate of hours required, based upon ordinary human experience aided by the expert opinions.
I accept the plaintiff's case that between the plaintiff's discharge from the rehabilitation hospital on 14 December 2012 and the end of February 2013, a period of 11.5 weeks, Ms Jansen's necessary attention to his care would have required on average 1.5 hours per day. The plaintiff's claim of half an hour per day from the beginning of March 2013 until he was admitted to hospital for surgery on 25 November 2013 (38.4 weeks) is also reasonable and justified on the evidence.
Upon discharge after his spinal surgery on 23 December 2013 Ms Jansen was again required to provide intensive domestic care. This was a period in which the plaintiff's migraines became severe, extremely debilitating and near continuous. They remained very disabling until the Botox injections began to provide some relief in the second half of the year. The plaintiff claims 2 hours per day for 9.6 weeks up to 28 February 2014, reducing to half an hour per day thereafter. I accept those figures as supported by the evidence. The claim continues to 28 February 2015 but I do not consider it justified beyond 30 June 2014. I will allow for half an hour per day up to the end of June 2014. By that time the plaintiff's balance had improved following the operation, to the point where he was able to commence attending the gym a little later in the year. I am satisfied he has been able to care for himself domestically from the second half of 2014.
The rate at which this care is claimed for is $29.98 per hour, which is not disputed. Upon the above findings the total amount to be allowed for past domestic care is $10,172.

[36]

These reasons were originally published to the parties on 17 May 2018 and orders were then made in accordance with these reasons, incorporating figures for workers compensation payments which had been tendered by Building Partners Pty Ltd and which the Court was subsequently advised were in error. The figures have been corrected in the reasons now republished to give effect to the corrections, pursuant to r 36.16(3B) of the Uniform Civil Procedure Rules 2005 (NSW). The orders of 17 May 2018 have been vacated and replaced with the following orders.
The orders of the Court in proceedings no 2015/111482 are: 1. The orders pronounced 17 May 2018 are vacated and the following orders are made in lieu. 2. Judgment for the plaintiff, Raymond Wharekawa, against the defendant, AEA Constructions Pty Ltd for $1,486,783. 3. The defendant, AEA Constructions Pty Ltd, is to pay the costs of the plaintiff. 4. Any application by the plaintiff, Raymond Wharekawa, with respect to the scale at which costs are to be paid under the costs order in his favour is to be made by notice of motion to be filed within seven days with a supporting affidavit and any written submissions. 5. The defendant is to file any affidavit and/or submissions in response within a further 14 days. 6. Upon AEA Constructions Pty Ltd filing its affidavit and any submissions in response to such applications with respect to costs, it is to notify the associate to Fagan J if it wishes to be heard in oral argument in opposition to the orders sought.
The orders of the Court in proceedings no 2016/129877 are: 1. The orders pronounced 17 May 2018 are vacated and the following orders are made in lieu. 2. Judgment for the plaintiff, Building Partners Pty Ltd, against the defendant, AEA Constructions Pty Ltd for $433,084.66, being made up of recovery pursuant to s 151Z of the Workers Compensation Act 1987 (NSW) in the sum of $365,085.66, plus interest in the sum of $67,999, on payments of workers compensation. 3. Noted that payment by the defendant, AEA Constructions Pty Ltd, of the judgment in order 2 above will operate as a credit in the sum of $365,085.66 against the judgment in favour of the plaintiff, Raymond Wharekawa under order 2 made this day in proceedings no 2015/111482. 4. The defendant, AEA Constructions Pty Ltd is to pay the costs of the plaintiff Building Partners Pty Ltd, of the proceedings. 5. Any application by Building Partners Pty Ltd with respect to the scale at which costs are to be paid under the costs orders in their favour is to be made by notice of motion to be filed within seven days with a supporting affidavit and any written submissions. 6. AEA Constructions Pty Ltd is to file any affidavit and/or submissions in response within a further 14 days. 7. Upon AEA Constructions Pty Ltd filing its affidavit and any submissions in response to such applications with respect to costs, it is to notify the associate to Fagan J if it wishes to be heard in oral argument in opposition to the orders sought.

Wharekawa v AEA Constructions Pty Ltd; Building Partners Pty Ltd v AEA Constructions Pty Ltd

At a glance

Court

Decision date

Before

Catchwords

Source

Catchwords

Judgment (37 paragraphs)

Legislation Cited (7)

Cases Cited (33)

Cited By (2)