WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; appeal against section 323 deduction where appellant underwent laminectomy and subsequent adjacent disc fusion in 1995; appellant had 7 years off and then obtained employment as long haul truck driver in 2003; in 2021 appellant developed symptoms in his back and came to a further fusion procedure in 2022, fusing the adjacent segment from the 1995 surgery; whether one-tenth deduction pursuant to section 323(2) erroneous; whether section 323 deduction for respiratory system assessment ought to have been made; Held - statutory assumption not available as adequate medical evidence available and at odds with 10% whole person impairment (WPI); Medical Assessor (MA) reasons inadequate; Donhad Pty Ltd v Asbury considered; evidence of long asymptomatic employment with appellant employer relevant to assessment of contribution; Medical Assessment Certificate (MAC) revoked and 25% deduction substituted; MA also failed to give adequate reasons re respiratory system assessment in the face of both specialists agreeing that deduction appropriate; MAC revoked; 40% deduction made.

1. On 22 August 2025 the appellant, Toll Transport Pty Ltd t/as Toll Global Logistics, lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr Peter Honeyman, a Medical Assessor, who issued an Amended Medical Assessment Certificate (MAC) on 25 July 2025.
2. The appellant relies on the following grounds of appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act):
   • the assessment was made on the basis of incorrect criteria, and
   • the MAC contains a demonstrable error.
3. The delegate is satisfied that, on the face of the application, at least one ground of appeal has been made out. The Appeal Panel has conducted a review of the original medical assessment but limited to the ground(s) of appeal on which the appeal is made.
4. Rule 128 of the Personal Injury Commission Rules 2021 (the PIC Rules) and Procedural Direction PIC7 - Appeals, reviews, reconsiderations and correction of obvious errors in medical disputes set out the practice and procedure in relation to the medical appeal process under s 328 of the 1998 Act. An Appeal Panel determines its own procedures in accordance with r 128(1) of the PIC Rules.
5. The assessment of permanent impairment is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed

1 March 2021 (the Guides) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5). "WPI" is reference to whole person impairment. "Baseline WPI" is a reference to the total WPI assessed before deduction for the effect of pre-existing injury, condition or abnormality pursuant to s 323 of the 1998 Act. "Assessor" is reference to Medical Assessor".

1. On 31 July 2025 an amended referral was made for a WPI assessment of injuries to the lumbar spine, respiratory system and scarring (TEMSKI) that occurred on 25 October 2021.
2. Mr Bullock was employed as a driver and had been working for the respondent since 2002. In 1994 he suffered an injury to his back, as a result of which he firstly underwent a laminectomy on 25 May 1995, which was revised on 2 November 1995 to a double fusion. He was off work for about seven years thereafter.
3. His work as a driver of heavy vehicles aggravated his back over the years until in 2021 he reported the problem. He came to a further fusion in 2022 whereby the metal from the two-level fusion was removed and extended, so that it became a three-level fusion. A spinal stimulator has subsequently been added to help with the pain.
4. Subsequently Mr Bullock developed sleep apnoea after putting on weight following the 2022 surgery. Mr Bullock estimated his weight at 100 kg at the time of the surgery and it is currently around 132 kg.
5. He has the use of a CPAP machine which has been beneficial in that his breathing is now reportedly good according to his wife, and he sleeps well.
6. The Medical Assessor assessed 26% WPI regarding the lumbar spine, from which he deducted one-tenth, leaving a subtotal of 23%. He found 8% for injury to the respiratory system and 2% for the scarring, leaving a combined table value of 30% WPI.

1. The Appeal Panel conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with the Procedural Direction PIC7.

1. The appellant employer sought that Mr Bullock be re-examined by a member of the Appeal Panel. However, as the issue was predominantly about the extent of the deduction pursuant to s 323 of the 1998 Act, the relevant evidence was before the Medical Assessor, and a re-examination would not have assisted our deliberations. The other issue concerned the assessment of injury to the respiratory system, and again that was concerned with the historical record, so that a re-examination would not have assisted our discussion.

1. The Appeal Panel has before it all the documents that were sent to the Medical Assessor for the original medical assessment and has taken them into account in making this determination.

1. The parts of the medical certificate given by the Medical Assessor that are relevant to the appeal are set out, where relevant, in the body of this decision.

1. Both parties made written submissions which have been considered below by the Appeal Panel.

1. The procedures on appeal are contained in s 328 of the 1998 Act. The appeal is to be by way of review of the original medical assessment but the review is limited to the grounds of appeal on which the appeal is made.
2. In Campbelltown City Council v Vegan [2006] NSWCA 284 the Court of Appeal held that the Appeal Panel is obliged to give reasons. Where there are disputes of fact it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. Where more than one conclusion is open, it will be necessary to explain why one conclusion is preferred. On the other hand, the reasons need not be extensive or provide a detailed explanation of the criteria applied by the medical professionals in reaching a professional judgement.

1. As noted under the relevant factual background, the Medical Assessor recognised that there was some complexity in the case when he said:

"The complexity is that he first injured his back in 1994 and underwent a laminectomy. In 1995 this was revised to a double fusion and he largely became pain-free but he was off work for about seven years."

1. The Medical Assessor also noted at the same point in taking the history, that the 2022 surgery removed metal from the two-level fusion and extended it up so that it was then a three-level fusion.
2. The Medical Assessor said:

"[Mr Bullock] says that at the time he went off work, he estimated he was 100 kg and he is currently around 132 kg."

1. On physical examination, the Medical Assessor said at [5] of the MAC:

Severe canal stenosis at L3/4, followed by L4/5. Severe facet joint osteoarthritis at L3/4 producing compression of both descending L4 roots in the lateral recesses. Impingement of the descending L5 nerve roots in the lateral recesses secondary to facet joint related osteophytes at L4/5. Compression of the right exiting L5 and descending S1 nerve roots secondary to an asymmetric, predominantly osteophytic right sided protrusion, also contributed by facet joint arthritis.

Essentially non-diagnostic scan at the level of previous instrumentation Low-grade right L2-3 paraforaminal annulus tear and disc bulge without neural impingement. Facet joint arthropathy

1. Post L3 to S1 fusion with extensive background granulation tissue and inflammatory changes in
2. the posterior vertebral soft tissue.

There is mild/moderate developmental canal stenosis at L3/4.

29/11/21 Dr Gehr IME: Supported worked cause to the renewed low back pain.

23/5/23 (after surgery) rates DRE4 without deduction for pre-existing surgery.

8/11/23 Dr Freiberg (sleep)IME: Confirms Sleep Apnoea, secondary to post injury developed obesity. Epworth 16

6/12/21 Dr Muratore IME: does not support work relatedness.

23/6/23 Dr Johnson (sleep) IME: Supports weight gain has contributed to diagnosis of sleep apnoea.

13/9/23 Dr Powell IME: does not support "employment" with Toll Holdings represents a substantial contributing factor in the progression of the pre-existing disease process and the subsequent need for surgery. He assesses DRE4 then deducts DRE4 for pre-existing surgery.

27/9/24 Dr Johnson IME: Assess Epworth score of 9, and WPI 6%."

1. At [7] of the MAC the Medical Assessor summarised Mr Bullock's case by saying:

"Degenerative changes at L3/4, secondary to a former double fusion at L4/5, L5/S1, associated with a radiculopathy, resulting in a further fusion of L3/4. Failure to control ongoing leg pains resulted in insertion of a spinal stimulator."

1. Paragraphs [8e] and [8f] are templated questions regarding previous injury, to which the Medical Assessor noted:

"Yes, as noted in the history, there was a previous 2 level fusion performed in 1995."

1. In giving his reasons for assessment at [10a] of the MAC the Medical Assessor explained his reasoning regarding the sleep apnoea condition, saying:[1]

"The Sleep Apnoea is assessed as well controlled with Epworth of 6. Using T13.4 p317, he fits class 1, with mid-range 5% WPI. He requires the ongoing use of CPAP to control his sleep apnoea, which adds 3% for treatment resulting in 8% WPI. I do not consider there is evidence of pre-existing sleep apnoea to warrant a deduction."

1. In considering the evidence before him at [10c] of the MAC the Medical Assessor said:[2]

"Dr Gehr and Dr Powel largely agree on diagnosis and rating; their disagreement lies in how to account for the existing fusion. Dr Gehr ignores the significant risk of fusion to the disc joint above, where as Dr Powel quotes this risk as 4% per year, so he considers the injury as not work related. I disagree.

Dr Freiberg has scored Epworth sleepiness at 16, with no pervious sleep apnoea, vs a later assessment by Dr Johnson at 9 with an assessment there was prior problems and that pain contributes to current sleepiness despite use of CPAP. I have assessed Epworth as further improved and that some sleep disturbances as pain related."

1. With regard to any deduction the following appeared at [11] of the MAC:

"11. DEDUCTION (IF ANY) FOR THE PROPORTION OF THE IMPAIRMENT THAT IS DUE TO PREVIOUS INJURY OR PRE-EXISTING CONDITION OR ABNORMALITY

a. In my opinion the worker suffers from the following relevant previous injuries, pre-existing conditions or abnormalities:

(i) There has been a previous fusion with acknowledged risks to the joint above.

b. He has been assessed regularly with medicals to drive heavy transport, which

includes assessments for sleep apnoea. Therefore, I it is reasonable to assume he had none at the time he stopped work.

b. The previous injury, pre-existing condition or abnormality directly contributes to the

following matters that were taken into account when assessing the whole person

impairment that results from the injury, being the matters taken into account in 10a, and in the following ways:

(i) His description of work involved no regular heavy work in loading and unloading goods.

(ii) Vibration is a recognised occupational risk for development and acceleration of back problems, and manufacturers of heavy transport vehicles build anti vibration into usual seating. I understand his work was mostly on sealed roads.

(iii) Extended sitting with unverifiable back support/posture is the suggested occupational component.

c. The extent of the deduction is difficult or costly to determine so in applying the provisions of s.323(2) I assess the deductible proportion as one tenth. (can only be used when not at odds with available evidence)"

1. The appellant employer noted that on 31 March 2022, Member Bachelor had found that the injury was "the aggravation of a significant pre-existing condition in the lumbar spine." There was an inconsistency between the extent of the s 323 deduction found by the Medical Assessor and the evidence before him, it was submitted.
2. It was further outlined that the Medical Assessor failed to have regard to available evidence regarding Mr Bullock's weight in respect of his respiratory condition.
3. The appellant employer submitted that where there had been an earlier fusion as was the case with Mr Bullock in 1995 with another employer, it could be expected that notwithstanding the successful outcome of the initial fusion, adjacent segment disc disease will probably follow. Thus, the impairment subsequent to a spinal fusion was not going to decrease over time but rather increase by virtue of the effects of the surgical process itself. This was illustrated by the history in the present case, where Mr Bullock had received compensation for his back injury prior to his employment with the appellant employer.
4. It was, submitted, hardly coincidental that the 2022 surgery was directed specifically at the adjacent level to the 1995 surgery.
5. There was no doubt, the appellant employer said, that the nature of the injury was the aggravation of Mr Bullock's spine whilst he was employed by the appellant employer, but it argued that the real question in the case was the extent to which the aggravation had contributed to the impairment now suffered.
6. The appellant employer argued that the very nature of the surgery in 1994 and 1995 would indicate a significant degree of impairment and of itself would probably have been classed as a DRE IV, had the Guides been applicable at the time.
7. Thus, it said, there was a measurable degree of impairment prior to the injury with the appellant employer which was significant.
8. The appellant employer noted that this this issue was engaged by the experts retained on both sides of the record and it submitted that the opinion of its medico-legal expert, Dr Powell should be preferred over the opinion of Mr Bullock's expert, Dr Gehr. Both experts provided subsequent reports justifying the approach taken, and both experts acknowledged the effect of Chapters 1.27 and 1.28 of the Guides regarding previous injuries.
9. In light of the thorough engagement by both medico-legal experts it was submitted that the Medical Assessor's consideration of the issue was "superficial" in that he did not discuss the significance of the earlier injury, which resulted in the 1995 surgery, nor did he attempt to separate out that prior impairment in determining the s 323 deduction.
10. The application of the one-tenth deduction pursuant to s 323(2), the appellant employer argued, was not applicable, as there was no absence of medical evidence in Mr Bullock's case.
11. The matters referred to by the Medical Assessor at [11] did not "squarely engage" with the relevant considerations, the appellant employer submitted. The engagement by both medicolegal experts with the issue demonstrated a need by the Medical Assessor to engage with s 323(1) rather than simply rely on the statutory assumption contained in s 323 (2).
12. The deduction of one-tenth was inconsistent with the evidence before the Medical Assessor, the appellant employer submitted.
13. Whilst Drs Gehr and Powell engaged with the process in subsequent reports, without any agreement as to the result, they both had a clear regard to the significance of the evidence and the relevant guidelines. The Medical Assessor, the appellant employer said, had not engaged with the significance of the earlier fusion, and had treated the issue superficially. He had not had regard to the degree of impairment that the former surgery had caused, nor to the deterioration that would be a natural consequence of that surgery.
14. This was a case, it was argued, in which the provisions of s 323(1) were applicable and there was no need to rely on the "fallback position" of s 323(2), which had been misapplied.
15. There was no basis for the assertion that it would be costly to engage in the process required under s 323(1). Moreover, it was argued, the Medical Assessor did not consider the additional reports of Dr Gehr or Dr Powell which specifically dealt with this issue.
16. The Medical Assessor appeared to have drawn "an artificial line" at the commencement of

Mr Bullock's employment with the appellant employer by ignoring the prior surgery and its contribution to the impairment caused by the subject injury, it was argued. 17. The evidence before the Medical Assessor demonstrated the nature of the earlier injury by contemporaneous reports and descriptions of the surgical procedures, the appellant employer noted. Accordingly, the extent of the deduction was not difficult or costly to determine as s 323(2) requires and therefore the sub-section had not been enlivened.

1. The appellant employer noted that the expert evidence in this regard came from respiratory physicians and that the question of Mr Bullock's weight was relevant. We referred to the various records regarding Mr Bullock's weight that were before the Medical Assessor.
2. Mr Bullock's expert, Dr Freiberg, had erred when he assumed that in October 2021

Mr Bullock weighed 95kg, the appellant employer said. This compromised his first report and although in his subsequent report Dr Freiberg obtained a correct history regarding the weight, he accepted the appropriateness of making a deduction for the pre-existing snoring and borderline obesity. 3. The appellant employer submitted that its expert, Dr Johnson, specifically engaged with the weight issue and Mr Bullock's pre-existing condition in his reports. 4. On the face of the MAC the Medical Assessor had failed to engage with this issue and it was submitted that his reasoning process regarding this aspect of the claim was "lacking." We were referred to Wingfoot Australia Partners Pty Ltd v Kocak[3] in that regard. 5. The appellant employer further submitted that the Medical Assessor had made a factual error in basing his opinion on an assumption that Mr Bullock weighed 100kg when he went off work, which was the same error made by Dr Freiberg in his first report. 6. Further, the observation by the Medical Assessor that he assessed the "Epworth sleepiness score at six," without explaining that finding was also a demonstrable error, as he failed to discuss the sleep studies, the clinical records as to weight, or provide adequate reasoning. The appellant employer also submitted that the statement "I do not consider there is evidence of pre-existing sleep apnoea to warrant a deduction" was not accompanied by any reasoning process, and did not have any regard to the opinions of both qualified respiratory physicians who had both considered the pre-existing borderline obesity in calculating the impairment.

1. Mr Bullock noted that the entire premise of the appeal regarding the lumbar spine assessment related to the assessment of the contribution by the proper application of s 323 of the 1998 Act.
2. Mr Bullock submitted firstly that the appellant employer's submissions were misconceived, as the Medical Assessor had done no more than exercise his function as described in Wingfoot.[4]
3. Mr Bullock submitted that Wingfoot was authority for the proposition that the Medical Assessor could not predicate his own conclusions on anything other than his own medical experience and own medical expertise. In making this assessment. Mr Bullock submitted that the Medical Assessor could not be bound by other opinions that were before him because of the dicta in Wingfoot.
4. The appellant employer's submission to the contrary were accordingly of "no moment".
5. Secondly, the appellant employer's submissions were "futile" because the reports of Dr Gehr and Dr Powell pertaining to the s 323 issue had been considered by the Medical Assessor in any event.
6. This, Mr Bullock said, was apparent from "page 6 of his MAC" - by which we assume

Mr Bullock was referring to the comments made by the Medical Assessor at [10c] of the MAC. 7. Thirdly, Mr Bullock submitted that the appellant employer had assumed effectively that a greater deduction was required simply because surgery had occurred many years before the subject injury. 8. Mr Bullock relied on the templated headings to [11] of the MAC, submitting that "considered fairly and read with the totality of the ... reasons," the Medical Assessor was cognisant that a consideration of the actual consequences that flowed from the pre-existing underlying issues had to be undertaken. 9. We were referred to Cole v Wenaline Pty Ltd[5] and it was submitted that in conformance with that decision, the Medical Assessor had considered the evidence as to the "actual consequences" of the earlier issues at [11b] of the MAC. 10. There was no error, it was submitted, by the Medical Assessor applying his own specialised knowledge, tailored to the facts of this particular matter. 11. We were also referred to Ryder v Sundance Bakehouse[6] and its well-known reference to the "but for" test. The Medical Assessor had, it was argued, considered the relevant evidence and the correct legal question. 12. We were again referred to Wingfoot where Mr Bullock repeated his argument that it was not of any moment what a layperson, or what earlier medico-legal doctors considered because the Medical Assessor was required to apply his own forensic analysis and reach his own determination. Logic, Mr Bullock said, demonstrated that the facts of this case did call for the application of s 323(2), as it was difficult to determine the extent any deduction for a 1995 surgery, where Mr Bullock had later worked since 2003 in long haul heavy vehicle driving work. 13. As to the appeal against the assessment of the respiratory system, Mr Bullock also submitted that it should be rejected. 14. The estimate of Mr Bullock's weight at 100kg was, it was submitted, of no moment in the context of the medical assessment and the medical dispute that the assessor was required to resolve. 15. The appellant employer had erred in its submissions inasmuch as it alleged that the Medical Assessor had based his assessment on Mr Bullock's lay estimation as it was not evident in the analytical parts of the MAC that the Medical Assessor did in fact, predicate his determinations on this opinion from Mr Bullock, it was submitted. 16. Mr Bullock again relied on the dicta in Wingfoot stating that the that the Medical Assessor "was not required to provide an opinion that was consistent with the medico-legal evidence." 17. The basis on which the Medical Assessor formed his conclusions were apparent, it was submitted, upon a "fair reading of the MAC". 18. The Medical Assessor was "not required to resolve the tension" between the expert opinion nor was he required to assess WPI in the manner which the appellant employer had suggested.

1. Section 323 of the 1998 act provides relevantly:

"(1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality.

(2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence."

1. In Donhad Pty Ltd v Asbury [7] Griffiths AJ summarised the relevant authority regarding the application of s 323, from [52]:

"52. The task of a medical assessor under s 323 was described by Schmidt J in Cole at [38]:

What s 323 required, however, was that the evidence be considered, so that it could be determined, firstly, what the level of impairment after the second injury was. Secondly, whether a proportion of that impairment was due to the first injury. Thirdly, what that proportion was. Undoubtedly in undertaking this exercise, the medical members of an Appeal Panel must utilise their medical judgment, knowledge and experience. Nevertheless, all stages of the statutory exercise must be taken in the light of the evidence and without the making of assumptions not provided for by the section.

1. Earlier in the reasons for judgment in Cole, her Honour made the following observations regarding s 323 (emphasis added):

29. ... The section is directed to a situation where there is a pre-existing injury, pre-existing condition or abnormality. For a deduction to be made from what has been assessed to have been the level of impairment which resulted from the later injury in question, a conclusion is required, on the evidence, that the pre-existing injury, pre-existing condition or abnormality caused or contributed to that impairment.

30. Section 323 does not permit that assessment to be made on the basis of an assumption or hypothesis, that once a particular injury has occurred, it will always, 'irrespective of outcome', contribute to the impairment flowing from any subsequent injury. The assessment must have regard to the evidence as to the actual consequences of the earlier injury, pre-existing condition or abnormality. The extent that the later impairment was due to the earlier injury, pre-existing condition or abnormality must be determined. The only exception is that provided for in s 323(2), where the required deduction 'will be difficult or costly to determine (because, for example, of the absence of medical evidence)'. In that case, an assumption is provided for, namely that the deduction 'is 10% of the impairment'. Even then, that assumption is displaced, if it is at odds with the available evidence

34. ... Section 323 requires that a conclusion be reached as to whether or not any proportion of permanent impairment assessed resulted from an earlier injury, pre-existing condition or abnormality. In a case such as this, that conclusion must be reached on the evidence led as to the actual consequences of the earlier and later injuries, unless the assumption provided in s 323(2) applies.

1. This approach was endorsed and explained by Campbell J in Ryder v Sundance Bakehouse [2015] NSWSC 526 at [45] (emphasis added):

What s 323 requires is an inquiry into whether there are other causes, (previous injury, or pre-existing abnormality), of an impairment caused by a work injury. A proportion of the impairment would be due to the pre-existing abnormality (even if that proportion cannot be precisely identified without difficulty or expense) only if it can be said that the pre-existing abnormality made a difference to the outcome in terms of the degree of impairment resulting from the work injury. If there is no difference in outcome, that is to say, if the degree of impairment is not greater than it would otherwise have been as a result of the injury, it is impossible to say that a proportion of it is due to the pre-existing abnormality. To put it another way, the Panel must be satisfied that but for the pre-existing abnormality, the degree of impairment resulting from the work injury would not have been as great.

1. Finally, it is desirable to note the following observations by Wright J in Southwell at [49]-[50] which also approve the approach in Cole:
   1. On its terms, however, s 323(2) does not apply if it has not been determined that a deduction is to be made under subs (1) because a part or portion of the level of impairment suffered was due to the pre-existing condition. Subsection (2) relates only to 'the extent of a deduction under this section' not to whether such a deduction is required. As Schmidt J held, in effect, in Cole v Wenaline Pty Ltd [2010] NSWSC 78 (Cole) at [30] and [31], s 323(1) does not permit the assessment of whether a deduction is required to be made on the basis of an assumption or hypothesis, that once there is found to be a particular pre-existing condition, it will always, 'irrespective of outcome', contribute to the impairment flowing from any subsequent injury. Rather, the assessment of whether a deduction is required must have regard to the evidence as to the actual consequences of the pre-existing condition and whether any proportion of the permanent impairment present after the workplace injury was due to the pre-existing condition.

50. Thus, it has been held, in cases such as Elcheikh v Diamond Formwork (NSW) Pty Ltd (in liq) [2013] NSWSC 365 at [126] (Schmidt J) and Secretary, Department of Communities and Justice v Lewandowski [2023] NSWSC 334 at [52] (Griffith AJ), that what must be determined under s 323 involves, at least, three enquiries:

• Firstly, what the extent of the resulting impairment is.

• Secondly, whether the pre-existing condition contributed to the impairment.

• Thirdly, if it did, what proportion of the impairment was due to the pre-existing condition."

1. The extent of the resulting impairment - here called the baseline WPI - is not in dispute, being assessed at 26%. The cause of the prior injury was also not in dispute, but the extent of its contribution to the baseline WPI was.
2. The appellant employer said that the prior injury of 1994 was responsible for a greater deduction than the statutory ten percent. A review of the relevant evidence is accordingly required.

1. Before embarking on that review, it is necessary to correct an apparent misconception in the assumption that underpinned many of Mr Bullock's submissions.
2. Mr Bullock is undoubtedly correct in his reliance on the dicta in Wingfoot, as far as it goes.
3. Mr Bullock cited the opinion of the plurality at [47] in his submissions:

"The function of a Medical Panel is to form and to give its own opinion on the medical question referred for its opinion. In performing that function, the

Medical Panel is doubtless obliged to observe procedural fairness, so as to

give an opportunity for parties to the underlying question or matter who will

be affected by the opinion to supply the Medical Panel with material which

may be relevant to the formulation of the opinion and to make submissions to the Medical Panel on the basis of that material. The material supplied may include the opinions of other medical practitioners, and submissions to the Medical Panel may seek to persuade the Medical Panel to adopt reasoning or conclusions expressed in those opinions. The Medical Panel may choose in a particular case to place weight on a medical opinion supplied to it in forming and giving its own opinion. It goes too far, however, to conceive of the function of the Panel as being either to decide a dispute or to make up its mind by reference to competing contentions or competing medical opinions. The function of a Medical Panel is neither arbitral nor adjudicative: it is neither to choose between competing arguments, nor to opine on the correctness of other opinions on that medical question. The function is in every case to form and to give its own opinion on the medical question referred to it by applying its own medical experience and its own medical expertise."

1. However that dicta does not, with respect, give a Medical Assessor a carte blanche, as

Mr Bullock appeared to assume. The High Court also stated at [48]:

"The reasons that (the legislation) obliges the medical panels are set out in a statement of reasons to accompany the certificate as to its opinion were the reasons which led the medical panel to form the opinion that the medical panel was required to form for itself on the medical question referred for its opinion. What is to be set out in the statement of reasons is the actual path of reasoning by which the medical panel arrives at the opinion the medical panel actually formed for itself."

1. In El Masri v Woolworths Ltd [2014] NSW SC 134 Campbell J said at 50 that:

"The statement of reasons must explain that actual path of reasoning in sufficient detail to enable a court to see whether the opinion does or does not involve any error of law."

1. In Vegan cited above, per Handley J (McColl JA agreeing):

"121 Where it is necessary for the Panel to make findings of primary fact, in order to reach a particular conclusion as to the existence, nature and extent of any physical impairment, it may be expected that the findings of material facts will be set out in its reasons. Where facts are in dispute, it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. More importantly, where more than one conclusion is open, it will be necessary for the Panel to give some explanation of its preference for one conclusion over another. That aspect may have particular significance in circumstances where the medical members of a Panel have made their own assessment of the applicant's condition and have come to a different conclusion from that reached by other medical practitioners, as set out in reports provided to the Panel.

122 On the other hand, to fulfil a minimum legal standard, the reasons need not be extensive or provide detailed explanation of the criteria applied by medical specialists in reaching a professional judgment: (authority omitted). At least, that will be so where the medical science is not controversial: if it is, a more expansive explanation may be required."

1. Accordingly, it was not quite correct, with respect, to submit as Mr Bullock did, that the opinions of other medico-legal specialists or indeed other evidence before the Medical Assessor was of "no moment".

1. The first ground of appeal was that the Medical Assessor had erred in applying the provisions of s 323 of the 1998 Act. As noted, the Medical Assessor determined that the statutory assumption of 1/10th provided by s 323(2) should be applied, saying at [10c]:

"Dr Gehr and Dr Powel largely agree on diagnosis and rating; their disagreement lies in how to account for the existing fusion. Dr Gehr ignores the significant risk of fusion to the disc joint above, where as Dr Powel quotes this risk as 4% per year, so he considers the injury as not work related. I disagree."

1. He also purported to explain the reasons for making the 1/10th deduction at [11]:

There has been a previous fusion with acknowledged risks to the joint above.

..He has been assessed regularly with medicals to drive heavy transport, which includes assessments for sleep apnoea. Therefore, I (sic) it is reasonable to assume he had none at the time he stopped work.

(i) His description of work involved no regular heavy work in loading and unloading

(ii) Vibration is a recognised occupational risk for development and acceleration of back problems, and manufacturers of heavy transport vehicles build anti vibration into usual seating. I understand his work was mostly on sealed roads.

(iii) Extended sitting with unverifiable back support/posture is the suggested occupational component.

c. The extent of the deduction is difficult or costly to determine so in applying the provisions of s.323(2) I assess the deductible proportion as one tenth. (can only be used when not at odds with available evidence)"

1. The comment in [11] that "it is reasonable to assume he had none at the time he stopped work" would seem to refer only to the sleep apnoea. Although the Medical Assessor acknowledged the previous fusion, his subsequent remarks at [11] were concerned with causation issues, which had already been accepted by the parties. He did not consider the extent to which the prior injury and subsequent surgery might contribute to the baseline impairment caused by the subject injury, as required by the above authorities.
2. The only opinion he gave was that contained in the template at paragraph [11c] - which include the words in parenthesis, "(can only be used when not at odds with the available evidence)". He made no attempt to justify his assessment, notwithstanding that at [8e and f] of the MAC he said that the cause of the pre-existing impairment was the 2-level fusion of 1995.
3. We found the summary of the reports of Dr Gehr and Dr Powell at [10c] to be unhelpful. The Medical Assessor appears to have rejected Dr Gehr's opinion, acknowledging that there was "a significant risk of fusion to the disc joint above" and he also rejected Dr Powell's estimate at "4% per year." He failed to advise which of the five reports from Dr Gehr he was referring to, nor which of the three reports from Dr Powell he relied on.
4. At [6] the Medical Assessor did nominate reports from Dr Gehr dated 29 November 2021 and 23 May 2023, and Dr Powell's report of 13 September 2023. However the mentions were brief, and not relevant to the question of pre-existing impairment.
5. The reasons given by the Medical Assessor were accordingly inadequate. We were unable to determine how it was he was able to determine that the statutory assumption of 10% was not at odds with the abundant evidence regarding the prior history that was before him. It is accordingly necessary to consider that evidence to establish the appropriate extent of the contribution by the past injury to the baseline impairment.

1. Dr Gehr, in his first report dated 29 November 2021 noted that there had been an L5 decompression and an L4-5 fusion "in the mid nineties". He said:[8]

"The injury occurred initially in 1994. He was working as a machine operator, at that time, he walked into the change room. At that time, he bent down to put on his boots and socks and he had pain in his lumbar spine going down both legs. He tells me he had two spinal operations, initially a laminectomy and then a two-level spinal fusion. Both operations were done by Dr. Giblin. He tells me the second operation helped.

Dr. Giblin in his note dated 8/11/2021 states he has a past history of an injury to his back, WC, and an L5 decompression, and L4/S1 fusion done at the time. He states that the pain settled down and went back to work, truck driving. He also states that his employment has been the main contributing factor to his current presentation. He states the original injury was to L4/5 and for that he had the spinal fusion and that over time he developed a degenerative spondylolisthesis of L3/4. He states in this note that this happens because of the fusion below and also due to the nature and conditions of his employment.

He tells me on 25/10/2021 he had the onset of severe lumbar spine pain and saw his GP. He tells me that pain had been building up for several months prior to that. He was sent for imaging."

1. In his summary Dr Gehr said that Mr Bullock had undergone the two spinal procedures in 1995. He said:

These surgical procedures were successful and allowed him to return to work as a truck driver. He had recurrence of symptoms in 2021. Had to stop work on 25/10/2021. He tells me prior to this date, he had been virtually pain free and able to work without the use of medication.

1. He did not assess any prior impairment, saying:

"I am not making a deduction for the previous spinal surgery as he had made a full recovery from it and is 20 years prior. It does not seem reasonable or rational to deduct this."

1. Dr Gehr repeated his opinion of 29 November 2021 when he next addressed the subject on 11 May 2024. He also diagnosed:[9]

"....I refer to my report dated 29/11/2021 in which I made the following diagnoses:

Lumbar spine pain with right radiculopathy with persisting symptoms despite discectomy and two level fusion 26 years ago. Further emergence of symptoms in 2021...."

1. Dr Gehr issued a further report dated 19 December 2024. He repeated his diagnosis and said relevantly:[10]

"[Dr Powell] has made a deduction for the previous two-level fusion. In doing so, he has arrived at a figure of WPI of 3%. I pointed out in both my reports why I did not make this deduction based on the following:

He had been able to return to heavy physical work after a successful outcome from a two-level fusion. It would appear to me to be unreasonable to make such a deduction where

the surgery was so successful.

I do note the reference in Guidelines page 6, paragraph 1.27, 1.28, however, I believe that assessors are at all times required to be reasonable in their determination of impairment. That is why I made no previous deduction given that he had been back at work for 20 years."

1. Dr Powell issued three reports to the respondent. On 13 September 2023 he said:[11]

"[Mr Bullock] has a long history of problems relating to the lower back. The initial injury occurred in 1994 as a result of lifting cables whilst in the employment of MM Cables.

Specialist opinion was obtained by Dr Matthew Giblin, who undertook an L5 decompression in 1994, followed by an L4 to S1 posterolateral instrumented fusion in

"In late 2021, Mr Bullock became aware of the gradual onset of lower back pain. There was no specific precipitating incident that he could recall. Symptoms developed over a period of several months.

His work as a truck driver involved the transferring of frames holding glass onto the tray of the semitrailer. These frames were suspended and Mr Bullock would reverse the truck underneath the load, which was then lowered onto it. He would then have to climb onto the tray of the truck to secure the load. He would then drive between

1. Dr Powell noted the diagnosis of adjacent segment disease, he said:

"[Investigations] indicated the fusion remained solid, though [Mr Bullock] had developed significant facet joint arthropathy at the L3/4 level with an associated spondylolisthesis. Degenerative disc changes were also noted at L2/3."

1. He recorded that Mr Bullock had come to surgery in the form of an extension of the posterolateral instrumented fusion to the L3/4 level in September 2022.
2. In assessing Mr Bullock's WPI, Dr Powell said:[13]

"Mr Bullock developed lower back symptoms in an insidious fashion without any specific precipitating incident almost 20 years after he commenced employment with Toll Holdings.

Investigations have confirmed the development of adjacent segment disease.

Dr Sergides, in his correspondence, dated 1 July 2022, quoted a paper "Sears et al Spine Journal 2011", that indicated the risk of the development of adjacent segment disease following a two-level fusion is approximately 4% per year.

It is clear from the information provided that Mr Bullock is suffering from a disease process involving the lumbar spine."

1. As to his assessment of the extent of any pre-existing impairment, Dr Powell said:[14]

"There is clear evidence of significant pre-existing pathology which needs to be taken into account. This represents the previous very successful fusion performed by

Dr Matthew Giblin. If this procedure were to be assessed in isolation it would be DRE Category IV with 20% whole person impairment (I have not included additional loading for the second fusion level as it is wholly deducted). After deduction of the 20% for the previous fusion, there is a nett whole person impairment of 3%. The higher level of deduction is justified on the basis of the well documented prior history of lower back problems and the fact that the level of pre-existing impairment can be easily calculated on the basis of the available information within the same Guidelines applied to the current level of assessment."

1. In his report dated 19 February 2024, Dr Powell said, when advising about other proposed treatment:[15]

"Mr Bullock is suffering from well established chronic lower back pain which has been present for over 30 years. He has undergone an extensive management programme including a series of surgical procedures including multilevel fusion. He has developed adjacent segment disease with progression of the degenerative disease process throughout the lumbar spine. He is now 63 years of age and in addition to his chronic lower back pain, has a number of significant comorbidities including peripheral neuropathy."

1. On 24 February 2025, Dr Powell confirmed his opinion on extensive questioning from his instructing solicitors regarding the opinions of Dr Gehr. In one answer, he said:[16]

".....There is clear evidence of significant pre-existing pathology in the lumbar spine that can be readily quantified. The development of adjacent segment disease following a spinal fusion is a well-documented and accepted condition in the medical literature. Mr Bullock's subsequent deterioration in his lumbar spine condition is consistent with the natural history of the pre-existing disease process."

1. Mr Bullock made three statements, the first being dated 14 December 2021, in which he described the circumstances of his injury:[17]

"6. I was getting sore in my back driving trucks for Toll and began noticing the soreness around four to six months before October 2021.

1. In my role, I was required to perform long haul trips on the freeway. My back would constantly get pounded against in the truck which was hurting my entire back.
2. I was also required to unload and reload trucks. This involved constantly going up and down, climbing in and out of the truck.
3. I had to put metal bars across the load to keep it square in the frame. The bars were around 3 to 5kg however, they could be difficult to move at times. If the bars were not square, it was difficult to pull the back of the trailer back into shape again. While doing this task, I was bending over and crouching trying to get it back into place again and this would hurt my back too.
4. I also had to climb up the back of trucks to get the front pusher off the frame which was at the front of the trailer. I had to reach inside to release the front pusher. The constant leaning would leave my back sore.
5. I have not returned to work since 23 October 2021."
6. We note that no mention was made of any vibration to either of the medicolegal specialist, and that history we assume came from the consultation between Mr Bullock and the Medical Assessor. We have already commented that the opinion by the Medical Assessor at [11] was outside his expertise, but its intent appeared to be to nullify the history of vibration being causative. The Medical Assessor said that because vibration was a recognised occupational risk that manufacturers of heavy transport vehicles had built anti vibration into the seating. From Mr Bullock's own description it appears that it was simply the rigours of driving heavy vehicles on long haul trips that aggravated his back.

1. Thus, the history taken by both medicolegal specialists and the Medical Assessor confirmed that the nature and conditions of Mr Bullock's employment with the appellant employer had aggravated the pre-existing pathology in his lumbar spine that had been the result of the two surgical procedures in 1995.
2. Dr Gehr found that Mr Bullock had a "recurrence of his symptoms," or a "further emergence of symptoms" in 2021. Dr Powell found that the lower back symptoms developed "in an insidious fashion without any specific precipitating incident almost 20 years after he commenced employment with Toll Holdings."
3. The reference to "4% per year" by the Medical Assessor was in fact a reference to an opinion by another specialist, Dr Segides, who had quoted a paper "Sears et al Spine Journal 2011", that indicated the risk of the development of adjacent segment disease following a two-level fusion is approximately 4% per year.
4. Dr Gehr did not differ from the opinion he reproduced by Dr Giblin, that the development of a degenerative spondylolisthesis at L3/4 following a spinal fusion at L4/5 happened because of the fusion below "and also due to the nature and conditions of [Mr Bullock's ] employment."
5. The original surgery by Dr Giblin on 25 May 1995 was a L5/S1 laminectomy. The subsequent revision of 2 November 1995 extended fusion to L4/S1. The opinion quoted by Dr Gehr was from a report by Dr Giblin dated 8 November 2021, lodged by the appellant employer.[18]

"A C.T. Scan has been done it confirms severe canal stenosis at L3/4 and I felt he had a bit of early spondylolisthesis at that level, it has been associated also with facet degenerative change. He has facet arthritis at L4/5 impinging the LS nerve roots.

Clinically, this gentleman's symptoms most likely relate to the degenerative changes at the level above his fusion."

1. Dr Giblin's opinion on 8 November 2021, therefore related to the then proposed surgery to the adjacent segment, namely L3/4, which occurred in September 2022 as a result of

Mr Bullock's employment with the appellant employer. 2. We confirm that diagnosis, and the validity of the opinion expressed by Dr Powell and

Dr Giblin (although Dr Giblin's report was not actually before us) that a fusion carries with it the probability that there will be a later development of adjacent segment disease. 3. The relevant question therefore is as to what proportion of the baseline WPI was due to

Mr Bullock's prior injury. 4. Dr Gehr's opinion was properly rejected by the Medical Assessor on the basis that he had ignored the "significant risk of fusion to the disc joint above." We would also observe that the authorities considered above do not include a test as to whether such a deduction were "reasonable or rational," so that Dr Gehr was applying incorrect test in any event to the application of s 323. Reference was made to the provisions of Chapters 1.27 and 1.28 of the Guides, which purport to be a summary of s 323, but it is the legislation which is binding. We note that Dr Gehr also appeared to believe that being reasonable was a test that excluded the provisions of Chapter 1.27 and 1.28. 5. Dr Powell, on the other hand, argued that the appellant employer was not liable because of the prior injury, which he argued had been the main contributing factor to Mr Bullock's injury, and not his employment with Toll Holdings. Be that as it may, Dr Powell nonetheless deducted 20%, being the minimum rating that can be given to a lumbar DRE category IV as provided by Table 15 - 3 of AMA5.[19] That, too, was not appropriate test the application of the section. 6. The appropriate test was discussed by Griffiths J in Asbury, above. To paraphrase Campbell J's dicta in Ryder, would the baseline impairment have been as great, but for Mr Bullock's prior injury? 7. It would appear that the date 25 October 2021 was agreed as the relevant date of injury, as that was the day Mr Bullock last worked. It was not alleged that there was any frank injury on that date, and the evidence confirms that the nature of the injury was the aggravation

Mr Bullock's previous 2-level fusion from 1995. That surgical procedure carries with it a strong chance that adjacent segment disease will follow, and we are satisfied that is what has occurred in Mr Bullock's case. 8. However, in applying the terms of the section, it is necessary to consider all the relevant evidence, and it is significant that Mr Bullock was able to work for 20 years doing the arduous and heavy work of a long-haul truck driver, as Mr Bullock described in his statement above, without symptoms. He only became symptomatic some six months before the date of injury, so that the consequences of the 1995 fusion could not be described as immediate. That they occurred eventually was not surprising, but the contribution by that arduous work to their occurrence is a matter that needs to be considered - especially after such a long period of quiescence. 9. This case does not fall within s 323(2), as there is adequate medical evidence to enable the decision to be made without recourse to the assumption contained therein. In all the circumstances we consider the extent of the contribution caused by the pre-existing adjacent segment disease to the baseline impairment as being 25%. 10. This ground accordingly succeeds.

1. The submissions from both parties were singularly lacking in reference to either legislation or authority.
2. The Medical Assessor explained his assessment at [10b] of his MAC, to repeat:

"The Sleep Apnoea is assessed as well controlled with Epworth of 6. Using T13.4 p317, he fits class 1, with mid-range 5% WPI. He requires the ongoing use of CPAP to control his sleep apnoea, which adds 3% for treatment resulting in 8% WPI. I do not consider there is evidence of pre existing sleep apnoea to warrant a deduction."

1. The Epworth scale is defined as the "Epworth Sleepiness Scale" at page 317 of AMA5:

"The clinician can evaluate sleepiness with the Epworth Sleepiness Scale,2 which assesses the likelihood of dozing (never = 0 to high chance = 3) in different situations: sitting and reading, watching television, sitting in a public place, riding as a passenger for an hour, taking an afternoon nap, sitting and talking to someone, sitting after a nonalcohol lunch, and stopped in traffic in a car. A score of 10/24 is equal to excessive sleepiness, or class 2 impairment. This scale correlates with the multiple sleep latency test (MSLT), which supports pathologic sleep in narcolepsy and idiopathic hypersomnia. See Table 13-4 for impairment due to sleep and arousal disorders."

Reduced daytime alertness; sleep pattern such that individual can perform most activities of daily living

Reduced daytime alertness; interferes with ability to perform some activities of daily living

Reduced daytime alertness; ability to perform activities of daily living significantly limited

Severe reduction of daytime alertness; individual unable to care for self in any situation or manner

Table 13-4 Criteria for Rating Impairment Due to Sleep and Arousal Disorders

1. Dr Freiberg, qualified for Mr Bullock, said in his report dated 8 November 2023:[20]

"At the time of his workplace injury on the 25 October 2024 [Mr Bullock] weighed 94kg or a BMI of 32."

1. This assumption was challenged by the appellant employer, and Dr Freiberg conceded such in his later report dated 29 November 2024:[21]

"At the time of my original IME assessment I was told that his weight prior to his workplace injury was 95kgs or a BMI of 32.

I note Dr Anthony Johnson in his report dated the 23rd June 2023 took a history that Mr Bullock reported his weight was 88-90kgs at the time of his workplace injury.

The most recent confirmed weight measure prior to his workplace injury was 11Bkgs on the 4th May 2019.

It was demonstrated on the 29th November 2021 that he was 120kgs. This is approximately one month after his workplace injury therefore Mr Bullock's history of a pre injury weight less than 100kgs is unlikely.

Applying the May 2019 confirmed measurement of pre injury weight at 11Bkgs...

1. Dr Freiberg's assessment in his first report was:[22]

"I would therefore classify Mr Bullock as a 20% Impairment of Whole Person due to sleep and arousal disorders. I would add 3% because he now requires long term nocturnal ventilation as a result of his workplace injury. I would deduct 5% because of his pre-existing intermittent snoring, borderline obesity, and Mallampati class 4 airway.

Therefore Mr Bullock has an 18% Whole Person Impairment due to sleep and arousal disorders."

1. In his second report, however, his opinion was:[23]

"I would therefore classify his impairment as a 9% Impairment of Whole Person due to sleep and arousal disorders.

Dr Anthony Johnson has done similar deductions and loadings for his pre existing obesity and narrow upper airway features as well as his need for CPAP therapy. Applying Dr Anthony Johnson's 2% deduction for the pre existing snoring and borderline obesity and 3% addition for the use of CPAP therapy this results in a 10% Impairment of Whole Person due to sleep and arousal disorders which is indeed a class 2 impairment....."

1. Dr Anthony Johnson, qualified for the appellant employer, said on 23 June 2023:[24]

"[Mr Bullock] estimates that he was approximately 88 - 90 kg in 1994 and a similar weight in 2002 when he went back to work as a truck driver. He did put some weight on during his time as a truck driver and I note he was unable to estimate it but I note that his weight on 23 February 2009 was recorded in the files at 115 kg. In May 2019 it was 118 kg."

"The relevant factors that contributed to his sleep apnoea would be his weight gain and I consider this to have likely been due to his inactivity as a result of working as a truck driver and then having a back injury and then back surgery. His weight gain would also be related to his diet including his alcohol consumption."

1. In a second report dated 27 September 2024, Dr Johnson said:[26]

"Using Work Cover Guides which amend the AMA guides to evaluation permanent impairment, fifth edition and using table 13.4 Criteria for impairment to sleep arousal disorder. His current sleep related impairment would be class 1, 1-9% impairment of the whole person, reduced day time alertness and sleep patterns such that he can perform most activities daily living and I assess his whole person impairment to his sleep arousal disorder to be 5%. He [sic - I] deducted 2% because of pre-existing intermittent snoring and borderline obesity I would add another 3% as he is required to use CPAP long-term, giving his whole person impairment due to his sleep and arousal disorder resulting from his work to be 6%."

1. On 25 February 2025 Dr Johnson wrote further in answer to queries from his retaining solicitors:[27]

"a.Noting the claimant was recorded by Dr Eugene Gehr on 29 November 2021 as weighing 120kg (some one month after he went off work complaining of back pain), do you agree with Dr Freiberg that it was impossible for Mr Bullock to have weighed "88-90kgs at the time of his workplace injury in October 2021" as he self-reported?

I would consider given the marked reduction in the weight gain documented, that it's likely that he had preexisting sleep apnoea and the 2 % deduction applied for preexisting borderline obesity in my original report is inadequate.

As in my previous report I assessed his whole person impairment due to his sleep and arousal disorder to be in Class 1, 5% whole person impairment. I deducted 2 % because of intermittent snoring and borderline obesity, but I would now deduct 3% due to this given his obesity was not borderline and add 3 % as he is required to use CPAP long term.

So I consider his whole person impairment due to his sleep and arousal disorder arising from his work as a truck driver to be 5%."

1. In discussing the evidence before him, the Medical Assessor said at [10c]:

"Dr Freiberg has scored Epworth sleepiness at 16, with no pervious sleep apnoea, vs a later assessment by Dr Johnson at 9 with an assessment there was prior problems and that pain contributes to current sleepiness despite use of CPAP. I have assessed Epworth as further improved and that some sleep disturbances as pain related."

1. In the light of the forgoing, it is difficult to resist the inference that the Medical Assessor had not fully considered the evidence before him. The issue was not that Dr Freiberg's assessment had been contradicted by the contemporaneous evidence about Mr Bullock's weight gain as relayed by Dr Johnson, but that Dr Freiberg himself had conceded that error, and reduced his assessment to 9% as a result.
2. The methodology was difficult to comprehend, but it seems that the experts in this field assess the Table 13-4 rating, reduce that amount by the contribution the pre-existing condition (in this case, weight) made, and then add an amount related to the use of the C-PAP machine. As noted, no submissions were made about the guidelines and we accordingly accept the methodology applied.
3. Another problem is that the specialists speak in terms of a percentage contribution to the Table 13-4 rating. Thus the final deduction made by Dr Johnson was 3% from the 5% WPI he assessed - an actual percentage contribution of 60%. Dr Freiberg originally deducted 5% from 20% - an actual percentage contribution of 20%. - and 2% from 9% in his second report - an actual percentage of 18%.
4. The Medical Assessor has not explained his comment that "I do not consider there is evidence of pre existing sleep apnoea to warrant a deduction", and in the face of the opinions from both specialists the comment does not acknowledge the common ground that, because of Mr Bullock's pre-existing weight, a deduction was called for. In view of the controversy on this subject this failure constituted error.
5. We are not confident about the reports of Dr Freiberg - particularly when he assessed a 5% deduction in his first report, but reduced it to 2% in his second, without any explanation other than he simply applied Dr Johnson's lesser estimate. The actual contribution has been assessed between 18% and 60%. Doing the best we can with the evidence we estimate the contribution to the baseline impairment for the respiratory system assessment to be 40%.
6. For these reasons, the Appeal Panel has determined that the MAC issued on 25 July 2025 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

Toll Transport Pty Ltd t/as Toll Global Logistics

This Certificate is issued pursuant to s 328(5) of the Workplace Injury Management and Workers Compensation Act 1998.

The Appeal Panel revokes the Medical Assessment Certificate of Medical Assessor Peter Honeyman and issues this new Medical Assessment Certificate as to the matters set out in the Table below:

Chapter, page, paragraph, figure and table numbers in AMA5

deductions pursuant to S323 for pre-existing injury, condition or abnormality

Sub-total/s % WPI (after any deductions in column 6)

Total % WPI (the Combined Table values of all sub-totals)

[3] [2013] HCA 43 at [48].

[4] Wingfoot Australia Partners Pty Ltd v Kocak [2013] HCA 43 (Wingfoot)

[5] [2010] NSWSC 78.

[6] [2015] NSWSC 526.

[7] [2025] NSWSC 1548.

[11] Appeal papers page 94. In fact Dr Giblin's contemporaneous reports demonstrate that the first surgery - "a right sided L5/S1 laminectomy, undercutting facectomy and neurolysis"- was performed on 25 May 1995. The revision surgery was performed on 2 November 1995 - "an L5/1 posterior interbody graft with L4/S1 postero-lateral graft with instrumentation." 12 Nothing turns on the inconsistency.