Plaintiff v First Defendant

2 Provisions of the Wrongs Act 1958 ('Wrongs Act') provide that to recover damages for non-economic loss for the initial injury, the defendant must establish that he has sustained a whole body impairment of greater than five per cent from that injury.[2] The assessment of impairment must disregard any impairment arising from the an unrelated injury or cause.[3] A medical panel appointed under the provisions of the Wrongs Act ('the Panel') determined that he met the threshold.[4]

3 By this proceeding, the plaintiff, which would be the defendant in any damages proceeding, seeks to challenge the determination of the Panel on a number of grounds. The plaintiff's central contention is that the method of assessment used by the Panel necessarily included a degree of impairment caused by the strokes and this offended the statutory requirement that any impairment resulting from the a cause other than the injury be ignored. It is also alleged that the Panel acted ultra vires because it did not have expertise in neurology.

4 In my view, the challenge to the composition of the Panel fails and the method adopted by the Panel was open to it. None of the grounds of challenge have been made out. The proceedings will be dismissed for the reasons that follow.

5 On the morning of 27 June 2014, the defendant tripped on a metal plate near the entrance of Gurners Lane, off Collins Street, Melbourne, and sustained an injury to his lower right leg ('the injury').

6 Immediately after sustaining the injury, the defendant attended the emergency department at St Vincent's Hospital where he was admitted and underwent surgical reduction and internal fixation to the fractures in his right lower leg and ankle.

7 Just over a year later, the defendant suffered at least two strokes requiring a long period of hospitalisation and rehabilitation. The strokes resulted in significant impairment to the right side of his body.

8 In a report obtained by the defendant, dated 2 May 2017, Dr David Kennedy, a sports and industrial physician, recorded that, as a result of his strokes, the defendant has clinical signs of a right hemiparesis[5] involving both his right upper and lower extremities. Dr Kennedy further recorded that, following the strokes, the defendant has dysphasia and a significant reduction in his use of his right arm and hand and a significant reduction in the use of his right lower leg, ankle and foot.

9 Dr Kennedy expressed the opinion that the defendant's injuries to the right ankle and hindfoot have stabilised and that he has significant restrictions in the use of his right lower leg, ankle and foot. Dr Kennedy said it was difficult to assess the level of impairment or prognosis in respect of the injury because the defendant has significant functional problems with his right lower extremity as a result of the strokes.

[The defendant] was assessed in accordance with the AMA Guides to the Evaluation of Permanent Impairment - 4th Edition, Chapter 3, Page 3/80 Tables 55 and 56. [The defendant] has an ankle impairment from ankylosis in a plantar flexion and varus position of greater than 30 degrees and this equates to a 21% whole person impairment. A proportion of this impairment assessment is due to the fact that [the defendant], subsequent to the incident on 27 June 2014, had a cerebrovascular accident on 15 July 2015 affecting the right side of his body. I would, therefore, apportion 70% of the ankle impairment due to the ankylosis to the cerebrovascular accident and 30% to the injuries sustained at the time of the incident on 27 June 2014.

11 On the same day, Dr Kennedy issued a certificate of assessment of impairment pursuant to s 28LN of the Wrongs Act which identified the injury as 'right ankle joint fractures with damage to the distal tibio fibula syndesmosis'. The certificate specified a degree of impairment resulting from the injury of more than five per cent.

12 A copy of the certificate and prescribed information was subsequently served on the plaintiff.

The referral of a medical question to the Panel

13 On 11 August 2017, the plaintiff referred the following medical question to a medical panel constituted under the Wrongs Act: '[d]oes the degree of impairment resulting from the physical injury to the claimant alleged in the claim satisfy the threshold level?' The alleged injury was identified as '[r]ight leg, right ankle, psychological and/or psychiatric'. It was noted that a certificate of assessment had been served with respect to physical injury only.

14 The Convenor of Medical Panels ('Convenor') did not immediately refer the medical question to a panel but sought further information about the defendant's medical condition. Following correspondence between the parties, on 6 September 2017, copies of various medical records, including imaging, and a copy of Dr Kennedy's report of 2 May 2017 were provided to the Convenor. On or around 20 September 2017, the Convenor appointed Professor Malcolm Sim, occupational physician, and Mr William Edwards, orthopaedic surgeon, to constitute a medical panel for the purposes of determining the medical question referred.

15 On 20 October 2017, the Convenor, on behalf of the Panel, wrote to the defendant's general practitioner requesting plain weight-bearing x-rays of the right ankle and foot including subtalar, talonavicular and calcaneocuboid joints with mortise, lateral and AP views. The letter stipulated that the x-rays should meet specific technical requirements, as outlined in an attached excerpt from the American Medical Association Guides to the Evaluation of Permanent Impairment (fourth edition) ('Guides'). Those x-rays were taken on 25 October 2017 and were provided to the Panel.

16 The defendant was examined by the Panel on 20 October 2017.

17 On 16 November 2017, the Panel, in answer to the question referred to it, determined that the degree of whole person impairment resulting from the physical injury to the claimant alleged in the claim satisfied the threshold level. On the same day, the Panel provided reasons for its determination.

18 The Panel's reasons set out a detailed history which it had obtained at its examination of the defendant. The history dealt separately with the period between the injury and the strokes and the period after the strokes. In relation to the former, the Panel noted:

The claimant told the Panel that in June 2015, which was prior to his strokes, he was still having considerable trouble with his right ankle and foot. He said that he had constant pain and he used to wake after three hours of sleeping due to pain. He said that the right foot was tilted outwards and downwards and he had limited ability to pull his foot upwards. He said this restricted movement of the right ankle and foot made walking difficult and he could only walk for about 15 to 20 minutes at a time. He said that he noticed that while walking the foot was not flat on the ground and was turned out. He said he was also having difficulty going up and down stairs (worse going down) and needed to step using one foot at a time. He said that he found it difficult to walk on uneven ground because of difficulty in raising the foot and he felt that the ankle would give way on him.

He said that his bicycle riding was also restricted and he was not able to return to running, which he did before the incident. He said he was able to return to work in the warehouse before his stroke, but he was still having problems with his right ankle.

The claimant told the Panel that prior to his strokes he was having physiotherapy for his ongoing right foot and ankle problems. He said he was referred to an occupational therapist for better management of the restricted movements of the right foot and ankle, but he was not able to go to this appointment because he suffered his strokes in July 2015.

19 The Panel then addressed the period following the strokes, noting from that time the defendant had considerable disability with severe restriction of power and movements of the right side of his body. The defendant told the Panel that he had some shoulder and hip movement but almost no movement in the more distal joints (elbow, wrist, hand, knee, ankle and foot). His speech had been affected but there had been recent improvement in that regard. His walking was greatly restricted and he used a motor scooter to move around when outside his residence. He told the Panel that he used a brace on the right ankle to raise his right foot.

20 The defendant also told the Panel he still had pain in his right ankle, but it was difficult for him to gauge how the pain had changed since the strokes because he has limited feeling in his right leg as a result of the strokes.

21 The Panel next set out the results of its physical examination of the defendant. Among other things, the Panel observed:

[The claimant] also had some increased foot progression. The claimant was noted to have his right upper limb held in flexion, consistent with a stroke, but the right foot was noted to be held in eversion and forward flexion, which the Panel considers is not consistent with the effects of a stroke. While standing, there was a navicular drop sign on the right. There was a valgus deformity of the right heel. The ankle was held in 25° of equinus and there was no active movement possible. There was clonus of the muscles of the right leg, which was consistent with the stroke. Knee power was 5/5, but there was grade 3 or 4 weakness in the muscle groups in the lower right leg and foot. There was a fixed 15° varus of the hindfoot, which was able to be corrected to 5° and there was reduced eversion. It was not possible to measure this accurately, as the foot was in varus.'[6]

22 It is convenient to interrupt the account of the Panel's reasons to identify some specific complaints about these passages. The plaintiff says that the Panel made internally inconsistent findings. First, it found that there was a valgus (away from the midline) deformity of the right heel while also finding that there was a fixed 15° varus (towards the midline) deformity of the hindfoot. Secondly, it found that there was a fixed 15° varus deformity of the hindfoot (meaning unable to be corrected passively) but said this could be corrected to 5°.[7] These criticisms fall within ground 5.

23 Returning then to the reasons, the Panel referred to several imaging reports taken following the injury, but before the strokes, including:

(a) an x-ray dated 27 June 2014 (before surgery) showing a minimally displaced posterior malleolus tibial fracture and a spiral fracture involving the distal third of the fibula shaft with mild lateral displacement of the distal fracture fragment;

(b) a postoperative x-ray dated 28 June 2014 showing internal fixation plates and screws in situ;

(c) x-rays of 7 August and 18 September 2014, the latter of which showed that the union of both fractures was still not complete;

(d) a CT scan of the right ankle dated 18 September 2014 showing the fracture sites still healing, diffuse osteopenia and a posterior talus serpiginous lucency with surrounding subarticular sclerosis; and

(e) an ultrasound of the mid/fore foot dated 9 October 2014 indicating limited dynamic assessment due to a decreased range of motion of the right ankle.

24 The Panel also noted the results of the additional weight-bearing x-rays that it had ordered which were performed on 25 October 2017. These x-rays showed that the fractures had healed, with the metal still in place, and that there was mild ankle joint space narrowing and moderate flattening of the tibia-os calculus angle.

25 Critically, the Panel concluded that the defendant is suffering from moderate continuing dysfunction of the right ankle following fractures of the distal tibia and fibula, which has resulted in avascular necrosis of the talus and severe dysfunction of the right tibialis posterior and the longitudinal arch of the right foot. It also concluded that the defendant's right foot and ankle condition had stabilised with no significant change over the preceding 12 months.

26 Based on that history and examination, the Panel proceeded to conduct an impairment assessment of the right ankle and right foot and scarring in accordance with the Guides.

27 The Panel said it had assessed impairment of the right ankle and foot in accordance with the specific procedures and directions in s 3.2 of the Guides. In relation to the right ankle, the Panel said it considered three methods to assess impairment: range of motion,[8] muscle atrophy[9] and arthritis.[10] Of those three potential methods, the Panel concluded that the range of motion method was the most appropriate because it was the most clinically specific method to assess the right ankle impairment.

28 As for the impairment of the right foot, the Panel said that the joint ankylosis method[11] and diagnosis-based estimates method[12] were the two most appropriate methods to assess impairment. Of those two methods, it considered the joint ankylosis method to be the most appropriate.

29 The Panel assessed the appropriate impairment for scarring of the right ankle in accordance with s 13.5 of the Guides. It then aggregated the three impairments in accordance with the combined value chart on p 322 of the Guides to give a single whole body impairment figure.

30 In undertaking its assessment the Panel directed itself to identify, and disregard, any impairment that 'may have been present prior to or occurred following' the injury. It explained that 'in performing the task of assessing any pre-existing impairment, the Panel must have an evidentiary basis on which it can be positively satisfied of pre-existing impairment which is to be disregarded'.

31 The Panel noted that the defendant had, at the time of injury, no pre-existing injury or any significant medical condition of his right foot or ankle but that subsequently the strokes had resulted in a right hemiparesis. On that basis, the Panel accepted there to be some impairment of the right ankle which must be disregarded pursuant to s 28LL(3) of the Wrongs Act. It regarded the decision of the Court of Appeal in Lingenberg v Gallichio as requiring it to 'do its best to evaluate the extent to which impairment from the unrelated injury or cause is playing a part in the [claimant's] current impairment'.[13]

After taking into account the right ankle impairment to be disregarded, the Panel combined the whole person impairments attributable to the physical injuries to the right ankle and foot using the formula prescribed at page 322 of the Guides and concluded that the degree of whole person impairment resulting from the physical injury to the claimant alleged in the claim is permanent and is more than 5%.

The Panel considers that it has assessed impairment arising from the claimant's physical injury alleged in the claim in accordance with the Guides and considers that further explanation or detailed reasons of the basis on which it has calculated impairment is prohibited by Section 28LZG(4) of the Act.

33 I interpolate that the Panel was precluded by s 28LN(2) from specifying the degree of impairment.

34 On 17 January 2018, the plaintiff commenced this proceeding seeking judicial review of the determination of the Panel. Following amendments to the originating process made by leave, the plaintiff now moves on the second amended originating motion[14] which contains six grounds of review.

35 In brief, the six grounds of review are as follows:

(a) Ground 1 - given that the defendant had suffered strokes, the Panel ought to have included a neurologist and the Panel, as constituted, acted ultra vires because it did not have the expertise to assess the impairment arising as a result of the strokes;

(b) Ground 1A - the Panel acted ultra vires because it was impossible for it to assess the degree of impairment attributable to the injury by reference to the Guides by reason of the 'dominant effect' of the strokes;

(c) Ground 2 - the Panel failed to take into account a mandatory relevant consideration, namely that impairments from unrelated injuries or causes are to be disregarded in making an assessment.[15] The error was said to arise because the range of motion and joint ankylosis methods necessarily included impairment arising from the strokes and the Panel failed to distinguish the two causes in its clinical findings.

(d) Ground 3 - the Panel failed to assess the defendant in accordance with the Guides because it applied the range of motion method when the defendant had no ability to move the ankle and it applied the joint ankylosis method when the defendant did not have ankle or foot ankylosis;

(e) Ground 4 - the Panel took into account irrelevant considerations by applying the range of motion method and the joint ankylosis method to assess impairment; and

(f) Ground 5 - the Panel made findings which no rational or logical medical panel, or no medical panel acting reasonably, could have made.

The evidence tendered by the plaintiff in support of the proceeding

36 Before dealing with the grounds, it is necessary to address the evidence sought to be tendered by the plaintiff in support of the proceeding.

37 In addition to the formal affidavits of record which are in unexceptionable terms and set out the material before the Panel and matters of process, the plaintiff also sought to tender three reports of Mr Michael Dooley, orthopaedic surgeon, dated 26 July 2018, 31 July 2018 and 6 September 2018. Self-evidently, those reports were not before the Panel at the time of its determination. The tender of the reports was opposed by the defendant on the ground of relevance.[16]

38 It is convenient to identify the substance of the reports of Mr Dooley in order to rule upon their admissibility.

39 Mr Dooley's first report was given in answer to a letter of instruction dated 12 July 2018 which contained 12 questions numbered 8(a) to (l). By questions 8(a) to (c) and (h), the plaintiff's solicitors asked Mr Dooley to define various medical terms used to describe movements and deformities of the foot and ankle. Those terms included inversion, eversion, equinus, varus, valgus, plantar flexion and dorsiflexion. Mr Dooley was also asked about the use of the phrase 'forward flexion' (which, it will be recalled, was used by the Panel to describe the position of the defendant's ankle).[17] Mr Dooley responded by giving a brief definition of each term adding that he '[did] not know what the term "forward flexion" pertains to'. He said that, in relation to the ankle, one uses the term plantar flexion (ie towards the ground) or dorsiflexion (ie towards the patient or roof).

40 Questions (d) to (g) were of a different kind and concerned the appropriate method of assessment of impairment under the Guides. Those questions, and the answers given by Mr Dooley to them in his first report, were as follows:

(d) Does a hemiparesis, caused by a stroke and with no active movement of the ankle or foot, impact upon the assessment of impairment of the affected ankle and foot? If yes, in what way does a stroke impact upon the assessment of impairment of the affected ankle and foot?

Yes. If one is assessing impairment of the ankle and hindfoot based on the AMA Fourth Edition Guidelines and using the range of motion model, then one is dependent on a patient having the ability to actively move the ankle and hindfoot joints. If they have had a stroke that has led to musculoskeletal weakness, spasticity, deformity etc, then assessing impairment of an injury separate to a stroke would be extraordinarily difficult using the range of motion model.

(e) Is the assessment of impairment of the foot and ankle undertaken pursuant to section 3.2e at page 77 of [the Guides], being the range of motion method, significantly affected by a hemiparesis where there is no active movement of the foot or ankle consequent to a stroke?

Yes. As outlined above.

(f) Is the assessment of impairment of an ankle and foot, in a person with a hemiparesis who has no active movement of the foot or ankle consequent to a stroke, most appropriately undertaken by applying:

(i) section 3.2i, the Diagnosis-Based Estimates assessment method at page 84, and Table 64 of the Guides? or

(ii) section 3.2e, the range of motion method, at page 77 of the Guides? or

(iii) section 3.2f, the joint ankyloses method, at page 79 of the Guides? or

(iv) other, and if so what, section of the Guides?

This is a very difficult question to answer. If one takes the type of ankle fracture that [the defendant] sustained, i.e. a standard closed Weber C fracture, then one would have expected following recovery for him to have had some mild restriction of range of motion, i.e. dorsiflexion and plantar flexion of the ankle joints. One would have expected him to have noted in time some intermittent ankle pain in relation to impact physical activity, prolonged walking and standing etc. The observation or development of flattening of the foot and valgus deformity at the midfoot three months or so post injury is very unusual. Very rarely in association with an ankle fracture, a rupture of the tibialis posterior tendon can occur. If this occurred and was not diagnosed, then in ·time planovalgus, i.e. valgus and flat foot deformity can occur. Investigation of [the defendant] showed that tibialis posterior tendon was intact. Minor tendinopathy at its insertion would be extraordinarily common in a patient of his age. A stroke resulting in a significant hemiparesis throws a large spanner in the works in relation to assessment of range of motion of the ankle joint and hindfoot. In time, in relation to a stroke consequent upon weakness and spasticity, fixed deformity can occur. There is no satisfactory classification in the Guides to allow assessment of impairment in this regard.

(g) In the absence of joint ankylosis, is the application of section 3.2f, the joint ankyloses method, at page 79 of the Guides appropriate in determining impairment?

In my view, [the defendant] did not develop ankylosis of the ankle joint, hindfoot etc consequent upon his ankle injury. I do not believe that one could use ankylosis as a satisfactory measurement of impairment etc in [the defendant's] case.

41 Mr Dooley was also asked questions on whether a vascular necrosis of the talus that occurred three years previously could be detected on plain x-ray and how the navicular drop test is performed.[18] As will appear, these questions relate to ground 5 which is to the effect that the Panel's finding that the defendant had an avascular necrosis of the right talus was not rational.

42 On those matters Mr Dooley responded that, although the CT scan recorded some subchondral lucency, this does not mean that the patient has a vascular necrosis of the talus. Mr Dooley further stated that he had never dealt with an ankle fracture that has resulted in avascular necrosis of the talus. He said that any vascular necrosis of the talus would have been evident on plain x-ray.

43 In relation to the navicular drop test, Mr Dooley said that navicular drop refers to the prominence of the navicular bone in the setting where a patient is developing planovalgus (flat foot deformity) and rarely is there any true abnormality involved.

44 In response to an invitation to express any further comments, Mr Dooley added the following:

I accept that I have the advantage of reading the Medical Panel report in an ivory tower position. I do have to admit however that I am confused by various aspects of the report. In relation to physical examination, it is outlined that there was a fixed fifteen degree varus deformity of the hindfoot. By fixed, this usually refers to a situation where the deformity is incorrigible, i.e. cannot be changed. It is then stated that the so called fixed deformity could be corrected by ten degrees. It is stated that eversion could not be measured because the foot was in varus. It was noted however that the foot was held in eversion, i.e. the opposite to varus. It is stated that [the defendant] has severe dysfunction of the right tibialis posterior tendon. It is stated on investigation that the tendon is intact and at most there is mild degeneration towards its insertion. I cannot reconcile these two statements.

It is stated that [the defendant] sustained fractures of the distal tibia and fibula. This is not the case. He sustained a so called Weber C type injury that involved disruption of the medial ligament, capsule of the ankle joint, inferior tibiofibular joint and fibula. There was no fracture of the distal tibia. It is stated that his fracture of the distal tibia and fibula resulted in avascular necrosis of the talus. In over thirty years of orthopaedic practice, I have never seen a situation where it has been suggested that a fracture of the ankle has resulted in avascular necrosis of the talus. I accept that one should never say never and never say always.

There is no doubt that trying to assess impairment in relation to a fractured ankle whereby a patient subsequently suffers a stroke resulting in a dense paresis is very difficult. [The defendant] sustained what would be considered a standard Weber C type fracture. Around three months later, it was noted that there was developing planovalgus deformity of the hindfoot and foot regions. The cause of this in my view is unclear. Any potential relationship of this condition to the injury and the fracture of the ankle is unclear.

45 In his second report of 31 July 2018, Mr Dooley said that the methods used by the Panel to assess impairment meant that the consequences of the strokes were the dominating factors in relation to restriction of the range of motion or any attempt to assess ankylosis.

46 In his third report dated 6 September 2018, Mr Dooley said the defendant's situation is very complex. He observed that trying to ascertain impairment in relation to the right ankle injury in the setting of a patient who has subsequently had a major stroke is very difficult. He summarised his opinion in the following terms:

I would readily accept that a legal practitioner might note that medical practitioners often talk in jargon, unintelligible abbreviations and forked tongues. This Medical Practitioner admits that he cannot understand the flow, logic, reasoning of the latter part of the Medical Panel opinion. The Panel seems to be saying that they have decided on an impairment rating in relation to [the defendant's] right ankle. They provide no figures, calculations etc. They discuss pre-existing impairment or impairment relating to other conditions post injury. The commentary is vague and justified by references to various judgements, appeals etc. They sign off by saying that they do not have to give any further explanation or detailed reasons. They also comment that they do not have to give any opinion in relation to whether or not impairment relates to the alleged injury. I am confused. Why bother having an assessment by a Medical Panel if that Panel does not have to comment on whether or not the claimed impairment relates to the injuries sustained, how they evaluated the level of impairment and how they took into account pre-existing or unrelated medical conditions.

As I have previously noted, [the defendant] sustained a Weber type C fracture of his right ankle in June of 2014. He underwent appropriate treatment in this regard. Several months later it was noted that [the defendant] had developed a planovalgus (flat foot) condition of the mid foot region. It is unclear as to why this occurred. In August of 2015 [the defendant] had a stroke that resulted in a right hemiparesis. X-rays three and a half years following the right ankle fracture show in my view no evidence of osteoarthritic change. They show a healed fracture. There is no evidence of avascular necrosis affecting the talus. It is unclear to me as to the relationship of the tibia-os calcus angle in terms of assessing impairment in relation a Weber C type fracture. You have pointed out that the Medical Panel has a requirement to undertake an impairment assessment pursuant to the Fourth Edition of the AMA Guides. Clearly I am not aware of the various Acts as outlined in the Medical Panel reports. In such a difficult situation, I believe that it would be beneficial for a Medical Panel to acknowledge the complexity of the case, impairment assessment etc. Explaining from a medical point of view that how they arrived at a certain impairment value would again be helpful. It would also allow others to conclude whether or not that assessment was reasonable and had taken into account the complexities of the case.

47 In summary, the reports of Mr Dooley contained the following opinions:

(a) the imposition of the strokes, with consequent restriction on movement of the right ankle and foot, meant that using the range of motion method was extremely difficult. That was because the motion was restricted by both the injury and the strokes and the latter had a dominating effect;

(b) the defendant did not have an ankylosis of the right ankle;

(c) the defendant did not have vascular necrosis of the talus and such a consequence would not, in Mr Dooley's experience, result from the injury;

(d) the relationship of the tibia-os calcus angle in terms of assessing impairment in relation a Weber C type fracture was unclear; and

(e) the Panel made inconsistent findings about the angle of the right foot, describing it as being in valgus and varus, and an error in describing a fracture of the distal tibia.

48 In order for the evidence of Mr Dooley to be admissible, it must be relevant.[19] In order to address the relevance of the reports, it is necessary to set out the statutory context in which the Panel made its decision and the nature of the jurisdiction being exercised by the Court on review.

49 Pursuant to s 28LE of the Wrongs Act, a person is not entitled to recover damages for non-economic loss in respect of an injury in any proceeding in a court unless the person has suffered significant injury. An injury (other than a psychiatric injury or spinal injury) will be a significant injury if the degree of impairment meets the threshold level of more than five per cent.[20] Impairment is defined to mean permanent impairment.[21]

50 Division 3 of pt VBA of the Wrongs Act prescribes the process of assessment of impairment and requires that an assessment of the degree of impairment be made 'in accordance with' the Guides.[22]

51 The statutory scheme provides, in the first instance, for the assessment of the degree of impairment to be undertaken by an approved medical practitioner in accordance with the Guides.[23] Section 28LN provides that the approved medical practitioner who makes an assessment must provide a certificate of assessment which states whether the injury satisfies the threshold level.[24] The certificate must not state the specific degree of impairment.[25] In this case, Dr Kennedy assessed the defendant's degree of impairment and issued a certificate stating that the injury satisfies the threshold level.

52 The certificate, together with other prescribed information, must be served on the respondent who is then required to respond.[26] A respondent on whom a certificate of assessment is served may refer a medical question in relation to the assessment to a medical panel for determination.[27]

53 Where, as in this case, the question asked of a medical panel requires it to determine whether or not the impairment of the claimant satisfies the threshold level, s 28LZG(1) of the Wrongs Act requires the medical panel to make an assessment of the impairment in accordance with div 3 of pt VBA which, in turn, requires it to make an assessment in accordance with the Guides.[28] In answering a medical question, a medical panel is not bound by rules or practices as to evidence and can inform itself on any matter in any manner it thinks fit.[29]

54 Section 28LZH provides that a determination by the medical panel of the kind made in this case 'must be accepted by a court in any proceeding on the claim is a determination of significant injury for the purposes of [pt VBA]'.

55 In the foreword to the Guides the following is said:

The Fourth Edition continues to convey several basic principles. A key tenet is that the book applies only to permanent impairments, which are defined as adverse conditions that are stable and unlikely to change. Evaluating the magnitude of these impairments is in the purview of the physician, while determining disability is usually not the physician's responsibility. This edition emphasizes that impairment percentages derived by using Guides criteria represent estimates rather than precise determinations. Permanent impairments are evaluated in terms of how they affect the patient's daily activities, and this edition recognizes that one's occupation constitutes part of his or her daily activities.

56 The Guides expressly state that the Guides do not and cannot provide answers about every type and degree of impairment.[30] The variety of human condition disease and treatment is enormous and depends very much on individual circumstances. The Guides emphasise that the physician's judgment and his or her experience, training, skill and thoroughness in examining the patient and applying the findings to the criteria will be factors in estimating the degree of the patient's impairment.[31] The Guides identify that there is an element of 'art' to the practice of medicine and in the application of the Guides to a particular patient.[32]

57 Chapter 3 of the Guides relates to the musculoskeletal system. The introductory passages to ch 3 record that examinations for determining musculoskeletal system impairments are based on traditional approaches for recording medical history and performing physical examination. The Guides state that '[t]he impairment examination and report should not be separated from the generally accepted principles of medical practice or the consensus of medical knowledge and experience.'[33] The introductory passages also note that ancillary tests and professional opinions that help to delineate the impairing condition may contribute to the impairment evaluation. A number of useful diagnostic procedures are identified, including CT scans and magnetic resonance imaging (MRI). However, it is said that such procedures are to be done only if necessary and relevant and should not be ordered without consideration of costs as well as benefits.[34]

58 The lower extremity, which includes the hip, leg, knee, ankle and foot, is dealt with in s 3.2 of ch 3. Section 3.2 sets out various evaluation methods which are appropriate for an assessment of impairment of the lower extremity. Notably, the introductory passages to s 3.2 include the following statement: '[s]electing the optimal approach or combining several methods requires judgment and experience. Also needed is careful testing that produces accurate and consistent results.'[35]

59 The methods of evaluating impairment include the range of motion method provided for in s 3.2e. As its title implies, the method requires the clinician to measure movement of the relevant joint and the range of motion is then translated, by the relevant table, to a level of impairment. For ankle motion table 42 is the applicable table and provides as follows:

Whole-person (lower extremity) [foot]

impairment

Mild:

3% (7%)

[10%]

Moderate:

6% (15%)

[21%]

Severe:

12% (30%)

43%

60 Section 3.2f describes the joint ankylosis method. Essentially, it provides for a level of impairment if a joint is fused or has been surgically fixed so that the joint cannot be moved (arthrodesis). If the joint is fixed or fused in a sub optimal position, when compared to an optimal neutral position, the magnitude of impairment is increased.

61 For example, in relation to the foot (which is divided into hindfoot, midfoot and forefoot) the table provides that for the subtalar part of the foot, the optimal ankylosis position is neutral, without varus or valgus. The ankylosis impairment in the neutral position is four per cent for the whole person impairment. Malpositioning may increase the impairment depending on the degree of variation from the optimal ankylosis position.

62 The Guides also attribute an impairment for the loss of the tibia-os calcis angle, which is the angle between the longitudinal axis of the os calcis (heel bone) and the tibia.[36]

63 Section 28LZI of the Wrongs Act provides that an assessment or determination of a medical panel is not amenable to merits review by a court. A determination of a medical panel may, however, be the subject of an application for judicial review.[37] A determination may be quashed if the panel falls into jurisdictional error by asking itself the wrong question, taking into account irrelevant considerations or failing to take into account relevant considerations. The factors that the panel is bound to consider is determined by reference to the statute conferring its jurisdiction (in this case, the Wrongs Act).[38]

64 Given the grounds invoked by the plaintiff, it is also necessary to refer to the principles that apply where it is contended that the exercise of power is legally unreasonable. If a decision made in the purported exercise of a statutory power is in breach of the standard of legal reasonableness, then the decision or action is outside the scope of the authority conferred by the statutory power.[39]

65 The relevant standard is a legal standard and is not breached merely because a court disagrees, even emphatically, with the merits of the decision. It arises because, as explained in Minister for Immigration and Citizenship v Li ('Li'), there is a presumption of law that Parliament intends an exercise of power to be reasonable.[40] Put another way, it is an implied condition of the statutory conferral of power that a statutory power must be exercised 'within the bounds of reasonableness'.[41] In Minister for Immigration and Border Protection v SZVFW ('SZVFW'), Gageler J said that '[t]he implication arises through the operation of a common law presumption of statutory interpretation that a statutory power is conferred on condition that the power can be exercised only within those bounds.'[42]

66 Any assessment of the legal reasonableness of a decision must occur within the particular statutory and factual setting in which a decision is made. Indeed, 'the indicia of legal unreasonableness will need to be found in the scope, subject and purpose of the particular statutory provisions in issue in any given case'.[43] Usually, that assessment will be directed to either the process of reasoning adopted by the decision-maker, as reflected in the reasons for decision, or the particular outcome of the exercise of power.

67 In Minister for Immigration and Border Protection v Singh ('Singh'), Allsop CJ, Robertson and Mortimer JJ referred to the judgments in Li as 'identify[ing] two different contexts in which the concept [of legal unreasonableness] is employed'.[44] First, legal unreasonableness 'can be a conclusion reached by a supervising court after the identification of an underlying jurisdictional error in the decision-making process'.[45] Second, there is what French CJ in Li labels 'an area of decisional freedom',[46] namely that 'legal unreasonableness can also be outcome focused, without necessarily identifying another underlying jurisdictional error'.[47]

68 Examined from either perspective it is necessary to determine whether the exercise of power is seen by the supervising court as lacking 'an evident and intelligible justification'.[48] The Wednesbury[49] formulation of unreasonableness, namely that the decision is one that no reasonable decision maker could have arrived at, is a way of expressing the conclusion that the decision lacks an intelligible justification.[50]

69 More specifically, in relation to decisions of a medical panel, Kyrou J, in H J Heinz Company Australia Ltd v Kotzman ('Heinz'), carefully set out some general principles relating to the interpretation of the Guides which I adopt: [51]

The interpretation of the Guides is a question of law. The determination of a level of impairment is a question of fact.

It has been said that to the extent that an Act requires determinations of impairment to be made in accordance with the Guides, the Guides has the force of law and is a legislative document.

However, the Guides is, as its title suggests, a guide. It was written by expert medical practitioners and not by statutory draftspeople, and should not be overlaid with legalistic - or a lawyer's precise - interpretation. It is of paramount importance to be faithful to the Guides' plain words. The Guides should not be interpreted as if it was a statute.

The use of the Guides is designed to promote precision, certainty and consistency. Its purpose is to make as objective as possible the process of estimating impairment by reference to sufficient medical and non-medical information to justify the estimate.

If there is any inconsistency between the [Accident Compensation] Act and the Guides, the [Accident Compensation] Act will prevail. If there is any inconsistency between the text in the Guides and an example which seeks to illustrate what is said in the text, the text will prevail.[52]

In order for a medical panel to assess impairment 'in accordance with the [Guides]' as required by s 91 of the [Accident Compensation] Act, it must act in conformity with the Guides. This means that it must apply the methodologies, processes and criteria set out in the Guides for the relevant condition, body part or system and adhere to any minimum or maximum values set out in the Guides for that condition, body part or system. Where the Guides contains a table that is applicable to a condition, body part or system, an assessment based on that table will not be in accordance with the Guides unless the categories, descriptions, criteria, ranges, adjustments and other elements of the table that are relevant to the condition, body part or system are adhered to and complied with.

Some provisions of the Guides, including some tables, provide alternative methodologies or set out ranges, and require the exercise of professional judgment in selecting the most appropriate methodology or in determining where in the range the relevant condition or body part falls. However, the Guides does not permit the exercise of professional judgment at large, unconstrained by the specific requirements of each methodology or table that it sets out. Once a particular methodology or table is selected, its requirements, including any limitations, must be applied in the manner set out by the Guides even if the outcome may appear sub-optimal. This is so because the role conferred by the [Accident Compensation] Act on a panel is not to arrive at a correct or fair assessment, but rather to arrive at an assessment that is the product of the application of the Guides.

The Guides itself makes it clear that the protocols and methodologies it sets out are intended to be standardised processes which produce similar outcomes irrespective of who conducts the assessment. In particular, the statement in s 1.2 of the Guides ... highlights that in order for an assessment to be in accordance with the Guides, the Panel must follow the protocols and tables in the Guides.[53]

71 I return now to the question of the admissibility of Mr Dooley's evidence. It is convenient to deal first with the admissibility of his evidence as to the meaning of certain medical terms which was contained in his first report in response to questions 8(a) to (c) and (h).[54]

72 In Heinz, Kyrou J concluded that the interpretation of the Guides is a question of law.[55] Whether the meaning of a word used in a statute or instrument is a question of fact or a question of law has been the subject of much learning, not all of which is easily reconcilable. There may be a difference between the process of ascribing meaning to words (which may be a question of fact) and the process of construction (a question of law).[56]

73 The question whether a word or phrase in a statute is to be given its ordinary meaning or some technical or other meaning is a question of law.[57]

74 In Victorian Workcover Authority v Elsdon,[58] the Court of Appeal considered whether expert evidence could be adduced as to the meaning of the word 'fractures' in the Guides. The majority held that the evidence was inadmissible because 'fractures' is an ordinary English word and not a specialised or technical term.[59] However, the majority went on to say that, subject to questions of relevance, a court may receive expert evidence in determining whether there is any specialised meaning of words or phrases and, if so, what that meaning is.[60]

75 However, the meaning of the words defined by Mr Dooley is not controversial. I do not require evidence in order to understand the medical terms used by the Panel. The majority of those terms appear in the Macquarie Dictionary. They describe a movement, or angle, of parts of the body and none of them require any particular medical knowledge in order to be understood.

76 In relation to the phrase 'forward flexion', neither party submitted that the Panel used it in a relevant technical sense and therefore evidence as to whether it is a technical term is irrelevant.

77 Nevertheless, and although it does not add much, I will admit the first report in so far as it defines terms in the answers given in 8(a) to 8(c).

78 The balance of Mr Dooley's reports contain more substantive content and are directed to the cogency of the Panel's assessment of impairment (and the reasons given by it) and certain of its findings.

79 As will appear, counsel submitted that grounds 1A, 2, 3 and 4 amount to a contention that it was not open to the Panel to conclude that the defendant satisfied the statutory threshold for significant injury. The making of a finding that is not open may amount to an error of law and such an error may be jurisdictional in nature.[61] However, the question is whether the finding was open to the decision maker on the material before it. On that basis, evidence that was not before the decision maker would, in the usual course, be irrelevant.

80 However, as developed in oral submissions the argument of the plaintiff went further with the end point of grounds 1A, 2, 3 and 4 being that the combination of the injury and the subsequent strokes meant that the defendant's impairment could never be assessed by a reasonable panel as satisfying the threshold requirement. The plaintiff submitted that the evidence of Mr Dooley was relevant to establish that it was effectively impossible to assess the impairment caused by the injury by reference to the Guides without regard to the impact of the strokes. It was also submitted that the joint ankylosis method was not available because the evidence of Mr Dooley established that the defendant did not have joint ankylosis. More generally, Mr Dooley says that the defendant's condition makes it almost impossible to apply all of the available aspects of the Guides to estimate impairment and that he could not understand the flow, logic, or reasoning of the Panel.

81 The plaintiff does advance a ground of legal unreasonableness under ground 5, however that ground is confined to certain findings of the Panel. The first is the finding that the defendant had avascular necrosis of the right talus. Secondly, the plaintiff claims that the Panel made two 'internally inconsistent examination findings', namely:

(a) that the defendant had a valgus (away from the midline) deformity of the right heel while, in the same paragraph, stating that there was a fixed 15° varus (towards the midline) deformity of the hindfoot; and

(b) that the defendant had a fixed 15° varus of the hindfoot (where 'fixed' means unable to be corrected passively) while stating that it could be corrected to 5°.

82 Mr Dooley's evidence identified the inconsistencies and, in relation to avascular necrosis, that he had never seen a situation where it was suggested that a fracture of the ankle has resulted in avascular necrosis of the talus[62] and that the x-rays provided no evidence of avascular necrosis affecting the talus.

83 I propose to consider the admissibility of the Dooley reports on the basis that grounds 1A, 2, 3, 4 and 5 amount to an argument based on legal unreasonableness, including under ground 5, on the basis of internally inconsistent or plainly erroneous findings of fact.

84 In the recent case of Port Phillip Scallops v Minister for Agriculture, [63] Cavanough J admitted expert evidence noting that it was common ground that where legal unreasonableness (amounting to claimed jurisdictional error) is alleged as a ground of review, evidence that was not before the decision maker may be admitted.[64] His Honour found that expert evidence not before the decision maker was admissible to support the plaintiff's contention that the impugned decisions were taken in disregard of, or contrary to, fundamental scientific knowledge and principles.[65]

85 In reaching that conclusion, Cavanough J relied on the decision of Weinberg J in Australian Retailers Association v Reserve Bank of Australia.[66] In that case, Weinberg J reluctantly admitted evidence from experts in economic theory addressing the issue of whether a decision of the Reserve Bank of Australia was irrational or not in accordance with sound economic principles. His Honour observed that:

Wednesbury unreasonableness is, in some respects, simply a variant of the ground that a decision-maker lacked jurisdiction to make the decision because jurisdiction was dependent on an actual state of facts that did not exist, or that the decision-maker based the decision on a finding of a particular fact that did not exist. If additional evidence is available, in cases reliant upon such grounds, there is no reason in principle why such evidence should not also be admissible where the ground is couched in terms of unreasonableness.[67]

86 His Honour went on to say that the tender of such evidence should not be encouraged, nor is such evidence admissible as of right.[68] Rather, the question of admissibility will turn on the grounds of review and the circumstances of the case.[69]

87 Not without a high degree of hesitation I propose to admit the three reports of Mr Dooley into evidence. I do so because, taken at its highest, the evidence is relevant to the plaintiff's argument that the assessment lacks an intelligible foundation in the reasons given by the Panel. Ultimately, questions of legal reasonableness are resolved in a particular statutory setting and here the body on whom the power is given is an expert panel whose opinion on medical questions is taken to be final. Such questions will almost invariably be determined by reference to the reasons of the decision maker and any error of the kind alleged will be apparent from the reasons and will not require, or benefit from, any elucidation by expert evidence.

88 Much of the opinion of Mr Dooley trespasses impermissibly on whether the conclusion reached by the Panel is the correct or preferable one having regard to medical practice. There is no role for evidence on that question because it is not the function of the court to determine the correct medical outcome.

89 However, I do not propose to descend to particular passages in the report, and the defendant did not submit that I should. I am prepared to accept that, on the plaintiff's submissions, the evidence is capable of advancing its case under grounds 1A, 2, 3 and 5. For that reason I will admit the reports.

90 Having dealt with the admissibility of Mr Dooley's evidence, I turn now to address the grounds of review.

91 By this ground, the plaintiff contends that the Panel did not have the expertise to assess the impairment arising from the strokes. The plaintiff submits that the Panel ought to have included a neurologist and that the failure to so constitute the Panel resulted in jurisdictional error. For the reasons that follow, I reject that contention.

92 'Medical panel' is defined in s 28LB of the Wrongs Act to mean a medical panel under the Workplace Injury Rehabilitation and Compensation Act 2013 ('WIRC Act'). Section 537 of the WIRC Act provides that medical panels must be constituted as necessary for the purpose of that Act, the Accident Compensation Act 1985 and pt VBA of the Wrongs Act to carry out such functions as may be conferred on a medical panel. For the purpose of constituting medical panels, there is a list of members consisting of medical practitioners nominated by the Minister on the recommendation of the Convenor and appointed by the Governor in Council.[70]

93 Section 537(7) of the WIRC Act provides that the Convenor may convene a medical panel and determine the number of members that are to constitute the panel based on what he or she considers to be appropriate in each particular case. Section 540 of the WIRC Act provides that an act or decision of a medical panel is not invalid by reason only of any defect or any irregularity in or in connection with the appointment of a member.

94 There is no express requirement that the Convenor constitute a panel in a particular way or with a particular level of expertise or specialty having regard to the particular medical condition of the person to be assessed. Nor can such a limit be implied into the terms of s 537(7). The issue is for the judgment of the Convenor who must constitute a panel on the basis of what the Convenor considers to be appropriate in each particular case.

95 The Convenor is not a party to the proceeding and the decision to appoint Professor Sim and Mr Edwards was not itself challenged. That would provide a sufficient basis for rejecting ground 1, however I do not rest my decision on that basis. More importantly, the argument advanced by ground 1 lacks a textual hook in either the Wrongs Act or the WIRC Act and would require the importation of a limitation on power that the provisions cannot bear.

96 The plaintiff relies on a statutory purpose of an expert determination of medical questions and submitted that this purpose is advanced by a legal requirement to constitute medical panels with appropriate expertise, which is presumably to be objectively determined. The purpose of the medical panel regime is, in the first place, to provide for a definitive medical determination of medical questions and avoid litigation on those issues. Given the conclusive nature of a determination by a medical panel, it may be expected that a panel will be constituted by practitioners with appropriate expertise. However, the choice is given to the Convenor. The improbability of requiring a specialist for each of the conditions from which a claimant may suffer renders the plaintiff's approach unlikely. The approach proposed by the plaintiff would lead to demarcation disputes between specialities, or even sub-specialities that would undermine the statutory purpose of avoiding litigation on medical questions.

97 Such an approach is also inconsistent with authority. A similar argument was considered and rejected by Maxwell P and Cavanough AJA in Gamble v Emerald Hill Electrical Pty Ltd ('Gamble').[71] The plaintiff sought to distinguish Gamble on the basis that Gamble was a case considering the provisions of the Accident Compensation Act and that, at the time, there was a statutory limit of five members per panel. It was submitted that the removal of the maximum number of panel members indicates that Parliament intended that the required medical expertise be present in a panel even if it meant that there were more than five members in total. Further, it was said there was a factual distinction because the Court in Gamble considered the position where a claimant might have many conditions whereas in this case the defendant has 'a fractured right ankle and the [s]troke only'. The plaintiff also sought to rely on a direction made by the Convenor pursuant to s 28LZ of the Wrongs Act to the effect that the Convenor will convene a medical panel appropriate in specialty and number for the consideration of the alleged injuries.[72]

98 None of those matters would lead me to distinguish Gamble. The purpose of the legislative scheme is to provide for expert, and definitive, assessment of impairment. In the present case, the Panel was constituted by medical practitioners and the sufficiency of their expertise was a matter for the Convenor to consider.

99 Given my conclusion, it is not necessary to consider whether s 540 of the WIRC Act would provide an answer to a challenge to a determination of a panel on the basis that it was irregularly constituted because it did not include a practitioner of a particular specialty.

100 I would also note, before leaving this point, the irony that the plaintiff sought to impugn the determination of the Panel by the evidence of an orthopaedic surgeon yet contended that only a neurologist had sufficient expertise to opine on the relationship between the defendant's impairment and the consequences of the strokes. That suggests that, in any event, the factual premise of the argument advanced under ground 1 is unsound.

101 Although these grounds were argued together and share a common foundation, namely that the defendant's impairment arising from the supervening catastrophic impairment caused by the strokes precluded the Panel from applying the Guides, it is nevertheless desirable to make brief reference to the specific submissions made under these grounds.

102 Under cover of this ground, which was added by leave at the hearing, the plaintiff contends that the Panel's determination was ultra vires because an assessment of impairment arising from the injury cannot be undertaken in accordance with the Guides. This ground was said to constitute a novel ground of judicial review that is judicially untested.

103 The premise underpinning the ground is that the strokes had produced such significant impairment of the right upper and lower limbs that any assessment of impairment of the right ankle or foot would necessarily include an assessment of the impairment arising from the strokes. In support of its argument, the plaintiff relied on the reports of Mr Dooley and, in particular, his opinion that the defendant's situation renders it 'almost impossible to apply all of the available aspects of the Guides to estimate impairment.'

104 By ground 2, the plaintiff submits that the Panel failed to take into account a relevant mandatory consideration, namely, the obligation imposed by the Wrongs Act to disregard any impairment arising from the strokes.[73]

105 It is submitted that the Panel failed to consider and undertake an appropriate examination so as to distinguish between impairment arising from the injury and that arising from the strokes. The plaintiff submits that the range of motion method was not an appropriate method to assess the defendant's right ankle impairment. That is because the range of motion method requires an assessment of the active range of motion that can be achieved by the patient and that, here, the defendant has no active movement of his ankle.

106 The plaintiff further submitted that the Panel did not determine which of its clinical findings arose from the fractures and which arose from the strokes. This submission is said to be underpinned by the failure of the Panel to obtain the evidence of the defendant's treating physiotherapist between June 2013 and October 2014 which would have provided an independent history of symptoms and findings relating to the right ankle and foot before the impact of the strokes. To the extent that the Panel did identify particular features associated with the strokes, it is said that the Panel made erroneous or inconsistent findings. The plaintiff alleges that the Panel made inconsistent findings as to the position of the defendant's right foot by stating that he held his right foot in valgus[74] while saying in the same paragraph that the right foot was held in varus.[75]

107 By ground 3, the plaintiff alleges a failure by the Panel to take into account mandatory relevant considerations in that it failed to assess the defendant's right foot in accordance with the Guides. In particular, the plaintiff alleges that the Panel:

(a) ignored the implicit requirement in the range of motion method that the defendant be able to autonomously move the relevant joint;

(b) assessed impairment of the right foot by means of the joint ankylosis method in circumstances where there was no factual or evidentiary basis to support the premise that the defendant had a joint ankylosis;

(c) failed to determine the defendant's tibio-os calcis angle as required by the joint ankylosis method (assuming that method was appropriate) and failed to assess the angle of the valgus deformity of the defendant's left heel;

(d) failed to identify the category of the tables in the Guides to which the Panel considered the defendant to fit;

(e) failed to obtain enough clinical information in order to characterise the impairment in accordance with the Guides, as prescribed in s 1.3 of the Guides;

(f) failed to obtain reports from the defendant's physiotherapist.

108 The plaintiff argues under ground 4 that the Panel took into account irrelevant considerations by:

(a) applying the range of motion method when there was no active movement of the joint;

(b) applying the joint ankylosis method in assessing impairment of the right ankle when there was no joint ankylosis.

109 Grounds 1A, 2, 3, and 4 provide different angles of attack on the same target and they were argued together.

110 The plaintiff's argument, as I apprehended it, had the following steps:

(a) the Panel was obliged to assess impairment in accordance with the Guides;

(b) the Panel was obliged to ignore any impairment arising from a condition or injury other than the claimed injury;

(c) the tables of ch 3 of the Guides are based on the active range of motion, which is determined with the patient's full effort and cooperation;

(d) application of the Guides to a range of motion requires that the patient have the capacity for active movement;

(e) the defendant had no active range of motion in his right ankle and this was a consequence of the strokes; and

(f) the impact of the strokes so dominated the defendant's presentation that, even if there was pre-existing impairment, it was overtaken by the impact of the strokes which meant that any assessment was, in substance, an assessment of the impairment arising from the strokes. Any such assessment necessarily offended s 28LL(3) of the Wrongs Act.

111 The plaintiff also contended that the joint ankylosis method was not available because the defendant did not have ankylosis. I will consider this aspect separately.

112 The first three steps may be accepted. The balance of the argument has both a factual and legal dimension.

113 The factual basis underpinning the grounds was that the strokes were the reason why there was no movement in the defendant's right ankle.

114 Approaching the matter by way of principle, the plaintiff makes two points. First, it contends that where the person is not able to actively and autonomously move the relevant joint the range of motion method of assessment is not available. Secondly, where the restriction on the ability to move the joint is caused, even in part by a supervening event (in this case the strokes), and the patient has no relevant movement, then any assessment of impairment using the range of motion method will necessarily, and impermissibly, take into account unrelated impairment.

115 I will deal first with the factual premise. The Panel drew a distinction between the clinical findings in relation to the upper limb, which it regarded as consistent with the strokes, and the clinical findings in relation to the right foot which the Panel said was 'held in eversion and forward flexion, which the Panel considers is not consistent with the effects of a stroke'.

116 In my view, the Panel found as a fact that there was a current or operative restriction on movement of the right foot that was caused by the fractures rather than the strokes. The Panel was conscious that it needed to differentiate between impairment resulting from the injury and that arising from the strokes. In that context, the conclusion that the defendant was suffering from moderate continuing dysfunction of the right ankle following fractures of the distal tibia and fibula was a finding that, at least in part, the defendant's impairment was caused by the injury. That finding of fact was one for the Panel to make. It brought its own expertise to its assessment and had the benefit of a physical examination of the defendant. No jurisdictional error has been established.

117 It follows that the factual premise of the plaintiff's submission has not been made out.

118 For the reasons that follow, there was also no error of principle in the Panel approaching the assessment in the manner that it did. First, the fact that there was no range of motion did not, of itself, preclude the Panel from applying the range of motion method.

119 The point of the range of motion method is to measure the capacity for movement and then use that measurement as a basis for the impairment assessment. It follows from the text of s 3.2e and Table 42 of the Guides that a person may have no movement but still have an impairment assessment undertaken using the range of motion method.

120 For example, Table 42, which relates to ankle motion impairments, identifies a relevant motion as plantar flexion capability and provides for three alternatives. Where the capability extends from 11° to 20°, the Table gives a mild degree of whole person impairment of 3 per cent. Where the flexion capability is 1° to 10°, the Table assigns a moderate impairment of 6 per cent. Finally, where there is no plantar flexion capability, the Table records a severe impairment of 12 per cent. This shows that it can be used where there is no relevant movement.

121 The second aspect of the submission raises for consideration the question whether the range of motion method inevitably had the consequence that the impairment assessment included a non-related cause in breach of s 28LL(3). It is desirable to start with some maters of principle.

The correct approach to disregarding non-related impairment

122 It was not controversial and follows from s 28LL(3) that, in making an impairment assessment, any impairment from an unrelated injury or cause must be disregarded so as to ensure that the impairment assessment relates solely to that resulting from the claimed injury. It would be inconsistent with that obligation for a medical panel to assess the impairment of an injured limb at large without adverting to the potential for impairment to be caused by different injuries or causes.[76] The medical panel is obliged to identify any impairment arising from an unrelated injury or cause, whether pre-existing or subsequent, and ensure that its estimate of impairment disregards any other impairment.[77]

123 In identifying the unrelated impairment, and in estimating its extent, the panel is not required to apply the Guides.[78] It is obliged to evaluate the unrelated impairment on the material presented to it and do its best to evaluate the extent to which that impairment is playing a part in the person's current impairment.[79] The process of attribution does not require the panel to speculate, but requires it to disregard any impairment, either pre-existing or post-dating the injury, which is established by evidence to have resulted from a cause other than the relevant injury.[80]

124 The purpose of the assessment is to identify a current or operative loss of function. If a supervening event results in a complete impairment of the relevant part of the body, in the sense of a complete loss of function, then it cannot be said that the initial injury is the cause of an ongoing or operative impairment. Amputation of a limb provides a paradigm example. If a person sustains an injury to the right ankle resulting in a certain level of impairment and subsequently has his or her leg amputated for an unrelated reason, the initial injury is not productive of any ongoing impairment.

125 If the supervening event is not of that extent, and there remains some level of impairment that relates to the initial injury, then it is necessary for a medical panel to assess the level of impairment using the Guides but disregard the level of impairment caused by the supervening event. This latter assessment requires some evidentiary basis but is not required to be undertaken in accordance with the Guides. There is no error in using the Guides to assess the overall current level of impairment and then disregarding any non-related impairment.

126 It is also important to recall that the Panel is prohibited from specifying the degree of impairment.[81] It is a corollary of that proposition that it may not be necessary to assess the degree of pre-existing or supervening impairment provided that the Panel can, having disregarded the unrelated impairment, be satisfied that the person reaches the threshold level.[82]

127 In Alcoa Holdings Ltd v Lowthian ('Alcoa'), J Forrest J said that it was open to a medical panel to assess current impairment (which may arise from more than one cause) and then isolate and disregard any impairment the decision maker is satisfied is from an unrelated injury or cause.[83] It is also open to a medical panel, using its collective expertise and knowledge, to estimate the extent of the compensable injury related impairment after taking into account and disregarding non-related impairment. That approach was endorsed by the Court of Appeal in Lingenberg v Gallichio.[84]

128 In its submission the plaintiff complained that by applying the range of motion method in circumstances where there was no movement automatically placed the defendant in the 'worst category'. In other words the defendant got the highest impairment level referrable to the ankle, although his actual impairment was contributed to in part by the strokes. So much may be accepted. However, the plaintiff's argument takes a false step in requiring the process to ignore the unrelated impairment at every stage of the assessment. As J Forrest J explained in Alcoa, the requirement to disregard impairment from an unrelated injury or cause can be done by assessing the overall level of impairment using the Guides and then quarantining that part of it which derives from an unrelated cause of injury.[85] This latter exercise involves maters of judgement and degree and need not be done in accordance with the Guides.

129 This approach reflects the structure of the Guides, which provide a means for assessing impairment of a relevant part of the body. The Guides provide an objective and readily replicable assessment of current impairment. Generally, assessment in accordance with the Guides does not involve or require any consideration of the cause that reduces the relevant impairment effect, although in certain parts it contemplates an apportionment based on pre-existing impairment.[86]

130 Where a particular part of the body is afflicted by two unrelated injuries or causes, applying the Guides to estimate current impairment of that body part will factor in both causes. That is what happened here.

131 The Panel assessed the range of motion that the defendant had in his right ankle, concluding that there was no active movement. It said expressly that the ankle was held on 25° of equinus and there was 'no active movement possible'. Using the method in Table 42 would produce a whole body impairment of 12 per cent. That level exceeds the threshold, however the 12 per cent impairment derived from applying the Guides necessarily includes a degree of impairment caused by the strokes because the Panel had accepted that the ankle impairment arose from a combination of the injury and the supervening strokes.

132 The plaintiff submits that this offends s 28LL(3). Had the Panel stopped its analysis at that point, the argument may have some merit. However, the Panel did not end its consideration there, rather, it proceeded to take into account the non-related impairment that it had found existed. In other words, the Panel's approach assessed the impairment caused by both conditions and then discounted or adjusted the impairment that was caused by the strokes. No mathematical precision was required.

133 In the circumstances, that approach was not impermissible provided, in its overall assessment of impairment, it took into account and disregarded any non-related impairment caused by the strokes.[87] The Panel did so and expressly adverted to the fact that it was not required to give a specific figure for the impairment. The Panel was not obliged to assess the amount of impairment attributable to the strokes using the Guides. In my view, that approach is consistent with that approved by J Forrest J in Alcoa.

134 The approach taken by the Panel did not lack an intelligible justification, even though, in its reasons, the Panel did not descend to the detail of the impairment that it attributed to the strokes. In that context it is important to reiterate that the Panel was prohibited from specifying the precise degree of impairment and it was not obliged to determine the level of impairment caused by non-related events in accordance with the Guides but rather was entitled to make an assessment using its professional skill and judgment.

135 It is clear that Mr Dooley regarded the problem as a difficult one and he doubted that the impairment could properly be assessed under the Guides. Indeed, the plaintiff submitted that the defendant's condition was not capable of being assessed under the Guides regardless of the method chosen. The opinion of Mr Dooley does not assist the plaintiff.

136 There is sufficient flexibility in the application of the Guides to allow the Panel to arrive at an impairment assessment of the ankle, foot and scarring using the methods adopted by the Panel and then allowing for a discount or reduction on account of extraneous impairment. That methodology is faithful to the statutory command that the impairment assessment be confined to impairment caused by the relevant injury.

137 Given the express statements by the Panel that it must identify and disregard any non-related impairment, the argument that it failed to take into account a relevant consideration or took into account an irrelevant consideration must fail. Further, the methodology employed provided an intelligible basis on which to assess impairment. Although the plaintiff submitted that the problem confronting the Panel was novel, in my view, the approach taken by J Forrest J in Alcoa provides a ready pathway to resolve what was admittedly a difficult conundrum.

138 In my opinion, the decision to assess the impairment of the right ankle by reference to the range of motion was open to the Panel and did not constitute a jurisdictional error on any of the bases alleged.

Grounds 3 and 4: the Panel's use of the joint ankylosis method

139 The Panel assessed impairment of the right foot using the joint ankylosis method set out in s 3.2f. I have described the general terms of 3.2f above.

140 The plaintiff submits that the joint ankylosis method was not available because the defendant does not have a fused right foot or malposition in angulation or rotation of a fused joint in his right foot. The plaintiff also submits that the Panel failed to measure the defendant's tibia-os calcis angle.

141 The determination of the appropriate method to assess impairment involved a matter of professional judgement and degree. It is clear from the text of s 3.2f that it is directed to joints that are fused or fixed. The Panel found that the right foot was held in a particular position that was not consistent with the effects of a stroke. That Mr Dooley would not have made the same finding is irrelevant. I note that Dr Kennedy in his report also described the defendant as having 'ankylosis and a fixed flexion deformity'. Ultimately, the determinations were matters of clinical judgment open to the Panel.

142 The Panel applied the joint ankylosis method to assess the impairment of the right foot, and said that it did so in accordance with the foot section in s 3.2f and table 60 of the Guides. Table 60 relates to impairment for loss of the tibia-os calcus angle based on a measurement of the tibia-os calcus angle shown in figure 57. It does not appear that, in addition to using table 60, the Panel also factored in foot impairment due to the angle at which the foot is fixed. In other words, the Panel's findings as to the angle of the foot (which was at least 5° varus) did not find reflection in the assessment of impairment, which was based on the moderate flattening of the tibia-os calcus angle using table 60. I am not persuaded that this approach involved legal error in circumstances which the Panel ultimately concluded that the combined effect exceeded the threshold level.

143 In my view, the findings that the lower right limb was fixed and could not move permitted the Panel to proceed on the basis provided for in s 3.2f of the Guides. Even if the Panel were wrong to do so, that error would not amount to a jurisdictional error because it was for the Panel to determine the appropriate methodology for assessment. It conducted an examination and, based on that examination, determined that the joint ankylosis method was the appropriate method to measure the impairment of the right foot. That conclusion was open to it as a matter of law.

144 Under this ground the plaintiff submitted that the Panel made an error of law by making findings which no rational or logical panel acting reasonably could have made.

145 The findings that were made by the Panel that underpinned this ground were as follows:

(a) the Panel failed to take into account the plain x-rays of the defendant's right foot and ankle undertaken on 20 October 2017 when finding that the defendant had a necrotic right talus consistent with avascular necrosis;

(b) the Panel recorded internally inconsistent findings that the defendant had:

(i) a valgus (away from the midline) deformity of the right heel and, as was stated later in the same paragraph, that there was a fixed 15° varus (towards the midline) deformity of the hind foot; and

(ii) a fixed 15° varus deformity of the hindfoot that could be corrected to 5°; and

(c) the Panel took into account a three-year old imaging report in determining that the defendant had avascular necrosis of the right talus.

146 The plaintiff submitted that findings of fact, including inferences, may be reviewed on the basis that there was no evidence to justify the making of the decision.[88] Accordingly, the plaintiff submitted that the failure of the Panel to consider the plain right ankle x-ray finding was unreasonable, as the x-ray did not show any evidence of avascular necrosis of the talus. In support of this submission, the plaintiff referred to s 2.4 of the Guides which states that medical evaluation of impairment includes reference to, amongst other things, radiographic studies.

147 Further, the plaintiff submitted that, in regards to the inconsistencies in the Panel's findings, the issue for consideration is whether the inconsistencies are so significant that the failure materially affects the ultimate decision.[89] The plaintiff submitted that there are multiple inconsistencies in the Panel's findings and that these inconsistencies identify that the assessment was not undertaken in accordance with the Guides. Accordingly, the plaintiff submitted that the decision of the Panel was unreasonable.

148 In my view, ground 5 is not made out and I am not satisfied that the errors, even if they were established, would amount to an exercise of power that was legally unreasonable. The particular matters relied on involved questions of fact. There is no jurisdictional error in simply making a wrong finding of fact.[90]

149 The Panel recorded its examination findings as revealing the right foot to be held in eversion with a valgus deformity of the right foot. This would mean the hindfoot is fixed at an angle away from the midline. In the same paragraph, the Panel recorded a fixed 15° varus of the hindfoot which could be corrected with reduced eversion, but the foot was in varus. That reveals a deformity towards the midline. It is possible the Panel made an error in its description or is describing different parts of the foot, each being at a different angle. Certainly, Dr Kennedy observes the right foot had a fixed inversion deformity and Mr Dooley said a valgus deformity would be unusual for the type of fracture sustained. Ultimately, I am not persuaded these errors, if they be such, constitute a judicial error or render the reasoning unintelligible.

150 The Panel had the benefit of an examination and concluded that there was some residual impairment from the injury that was separate to that caused by the strokes. Matters of expression and the accuracy of clinical findings on examination might be relevant in a consideration of the merits of the opinion, however they do not render the conclusion an invalid exercise of power.

151 I am also not persuaded that any error in the description of the angle of deformity of the ankle and foot was material to the result. That is because, in relation to the foot the Panel measured the range of movement and the angle in which the ankle and foot were fixed was not relevant to that assessment. In relation to the foot, the Panel applied the joint ankylosis method and specifically applied table 60 which is only concerned with the tibia-os calcus angle. There was radiological evidence of a moderate flattening of the tibia-os calcus angle which would have been sufficient to attract a whole person impairment of at least 10 per cent in table 60.

152 Further, I am not persuaded that any misdescription in the angle of deformity of the ankle and foot, infected the Panel's ultimate conclusion that there was a degree of continuing impairment arising from the injury. Nor has it been shown to have materially affected the apportionment undertaken by the Panel as between the injury and the strokes. That is particularly so where the Panel was precluded from specifying the degree of impairment and under no obligation to give a mathematical apportionment between the different causes.

153 The Panel was under no obligation to undertake further tests or to obtain information from treating practitioners including the physiotherapist. It was a matter for the Panel to determine whether it had sufficient information before it in order to make the required assessment of impairment. Similarly, it is not open to the plaintiff to say that the failure to have regard to particular images constituted a failure to have regard to a relevant consideration. The considerations to which the Panel must have had regard were those that the statute required it to consider. Particular x-rays were no more than pieces of evidence that were before the Panel. There is no jurisdictional error in not referring to particular pieces of evidence provided the Panel directs itself to the correct legal question.

154 In my opinion, the decision of the Panel is not in breach of the standard of legal reasonableness. There was no jurisdictional error in the decision-making process of the Panel that would lead me to a conclusion of legal unreasonableness. Further, the Panel's decision does not lack an evident and intelligible justification. Accordingly, the decision is not outside the scope of the authority conferred on the Panel by the Wrongs Act.

155 For the above reasons, the application should be dismissed as none of the grounds have been made out. I shall hear from the parties on the form of orders and on the question of costs.

[1] The second and third defendants filed a submitting appearance. It is convenient to describe the first defendant simply as the defendant in these reasons.

[2] Wrongs Act 1958 ss 28LE, 28LF, 28LB (definition of 'threshold level') ('Wrongs Act').

[3] Ibid s 28LL(3).

[4] The two members of the Panel are the second and third defendants.

[5] Hemiparesis means partial paralysis.

[8] American Medical Association's Guides to the Evaluation of Permanent Impairment (Fourth Edition) s 3.2e ('Guides').

[13] [2013] VSCA 143; (2013) 40 VR 60, 68 [29], citing Alcoa Holdings Ltd & Anor v Lowthian & Ors and De Haas [2011] VSC 245 [73] ('Alcoa').

[14] The second amended originating motion is dated 24 October 2018.

[15] Wrongs Act s 28LL.

[16] Evidence Act 2008 ss 55, 56 ('Evidence Act').

[17] See [21] above.

[19] Evidence Act ss 55, 56.

[20] Wrongs Act s 28LB (definition of 'threshold level').

[21] Ibid s 28LB (definition of 'impairment').

[22] Ibid s 28LH(1).

[23] Ibid ss 28LG, 28LH(1).

[24] Ibid s 28LN.

[25] Ibid s 28LN(2).

[26] Ibid ss 28LT, 28LW.

[27] Ibid s 28LWE.

[28] Ibid s 28LH(1).

[29] Ibid s 28LZ(1).

[30] Guides s 1.3.

[37] Supreme Court (General Civil Procedure) Rules 2015 ord 56.

[38] H J Heinz Company Limited v Kotzman [2009] VSC 311 [38] ('Heinz'), citing Minister for Aboriginal Affairs v Peko-Wallsend Ltd [1986] HCA 40; (1986) 162 CLR 24, 39 ('Peko-Wallsend').

[39] Minister for Immigration and Border Protection v SZCFW [2018] HCA 30 [53] (Gageler J) ('SZVFW').

[40] [2013] HCA 18; (2013) 249 CLR 332, 351 [29] (French CJ), 362 [63] (Hayne, Kiefel and Bell JJ), 370 [88] (Gageler J) ('Li'), cited in Minister for Immigration and Border Protection v Singh [2014] FCAFC 1; (2014) 231 FCR 437, 445 ('Singh').

[41] SZCFW [2018] HCA 30 [53] (Gageler J).

[43] Singh [2014] FCAFC 1; (2014) 231 FCR 437, 447.

[45] Ibid, citing Li [2013] HCA 18; (2013) 249 CLR 332, 350-1 [27]-[28] (French CJ), 365-6 [72] (Hayne, Kiefel and Bell JJ).

[46] Li [2013] HCA 18; (2013) 249 CLR 332, 351 [28].

[47] Singh [2014] FCAFC 1; (2014) 231 FCR 437, 445.

[48] Li [2013] HCA 18; (2013) 249 CLR 332, 367 [76] (Hayne, Kiefel and Bell JJ); Singh [2014] FCAFC 1; (2014) 231 FCR 437, 443.

[49] Associated Provincial Picture House Ltd v Wednesbury Corporation [1947] EWCA Civ 1; [1948] 1 KB 223.

[50] SZVFW [2018] HCA 30 [10] (Kiefel CJ).

[51] See also, State of Victoria v Jerak [2018] VSC 680 [54]; Pickett v Parks Victoria & Ors [2018] VSC 473 [21]; Hart v Melbourne Underwater World Pty Ltd [2018] VSC 394 [8].

[52] [2009] VSC 311 [24]-[28] (citations omitted).

[53] Ibid [45]-[47] (citations omitted).

[54] The terms defined by Mr Dooley are set out above at [39].

[55] Heinz [2009] VSC 311 [24].

[56] Hope v Bathurst City Council [1980] HCA 16; (1980) 144 CLR 1, 7 (Mason J). Cf Collector of Customs v Agfa-Gevaert Ltd [1996] HCA 36; (1996) 186 CLR 389, 396-7 ('Agfa-Gevaert').

[57] Collector of Customs v Pozzolanic Enterprises Pty Ltd [1993] FCA 456; (1993) 43 FCR 280, 287, cited in Agfa-Gevaert [1996] HCA 36; (1996) 186 CLR 389, 395.

[58] [2013] VSCA 235; (2013) 42 VR 434.

[60] Victorian Workcover Authority v Elsdon [2013] VSCA 235; (2013) 42 VR 434, 454 [84], quoting Woodward v Repatriation Commission [2003] FCAFC 160; (2003) 131 FCR 473, 493-4 [113].

[61] S v Crimes Compensation Tribunal [1998] 1 VR 83, 89-90 (Phillips JA).

[63] [2018] VSC 589.

[66] [2005] FCA 1707; (2005) 148 FCR 446.

[70] Workplace Injury Rehabilitation and Compensation Act 2013 s 537(2) ('WIRC Act').

[71] [2012] VSCA 322; (2012) 38 VR 45, 56 [40] ('Gamble').

[72] Convenor's Directions as to the Procedures of Medical Panels (under Part VBA of the Wrongs Act 1958) 2015, Direction 30.

[73] Wrongs Act s 28LL(3).

[76] Chua v Newman-Morris [2009] VSC 582 [36].

[77] Alcoa [2011] VSC 245 [66].

[78] Ibid [67]; Chua v Lowthian [2011] VSC 468 [132].

[79] Alcoa [2011] VSC 245 [73].

[80] Chua v Lowthian [2011] VSC 468 [124].

[81] Wrongs Act ss 28LN(2), 28LZG(4).

[82] Chua v Lowthian [2011] VSC 468 [133].

[83] [2011] VSC 245 [66].

[84] [2013] VSCA 143; (2013) 40 VR 60, 68-9 [30].

[85] Alcoa [2011] VSC 245 [66].

[87] Alcoa [2011] VSC 245 [74].

[88] The plaintiff's submissions cite Australian Broadcasting Tribunal v Bond [1990] HCA 33; (1990) 170 CLR 321, 355, 359.

[89] The plaintiff's submissions cite Peko-Wallsend [1986] HCA 40; (1986) 162 CLR 24, [40].

[90] Waterford v The Commonwealth (1987) 163 CLR 52, 77 (Brennan J).