WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; appeal against Medical Assessor's (MA) assessment of permanent impairment of the lumbar spine and the left lower extremity (hip); the MA erred in assessing permanent impairment when the appellant was scheduled to have hip replacement surgery in the imminent future; demonstrable error; application of incorrect criteria as the MA did not defer the medical assessment (in accordance with cls 1.15 and 1.16 of the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed 1 March 2021 (the Guidelines); re-assessment required once appellant's condition had stabilised; re-assessment to consider permanent impairment of the left lower extremity (hip), permanent impairment of the lumbar spine, and any deduction to the assessed impairment findings necessary pursuant to section 323; New South Wales Police Force v Registrar of the Workers Compensation Commission of New South Wales, Queanbeyan Racing Club Ltd v Burton, Merza v Registrar of the Workers Compensation Commission and Anor, Cole v Wenaline Pty Limited, and Ryder v Sundance Bakehouse considered; Held - Medical Assessment Certificate (MAC) revoked; new MAC unable to be issued at this time pending the stabilisation of the appellant's condition.

1. On 16 April 2025, Kim Daley (the appellant) lodged an Application to Appeal against the Decision of a Medical Assessor (the Appeal). The relevant medical dispute between the parties was assessed by Medical Assessor Todd Gothelf (the Medical Assessor), who issued a Medical Assessment Certificate (MAC) on 21 March 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 President's delegate was satisfied (in accordance with her 21 May 2025 direction) that, on the face of the Appeal, at least one ground of appeal has been made out. The Appeal Panel was therefore convened, and it has conducted a review of the original medical assessment, limited though to the grounds of appeal on which the Appeal is made.
4. Clause 128 of the Personal Injury Commission Rules 2021 (the Rules) and Procedural Direction PIC7 set out the practice and procedure in relation to the appeal process under s 328 of the 1998 Act. An appeal panel determines its own procedures in accordance with cl 128(1) of the Rules.
5. The relevant assessment of permanent impairment the subject of the medical dispute between the parties is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed, 1 March 2021 (the Guidelines), and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5).

1. The appellant has been employed by the NSW Police Force (the respondent) since she was attested as a constable on 21 December 1999. She became a senior constable on

28 February 2007, and continues in this role. 2. She sustained injury to her lower back and to her left groin/hip area while undertaking training in the course of her employment with the respondent, on 29 November 2022. She explains in her 30 July 2024 statement (found at page 5 of the Application to Resolve a Dispute (ARD)) that she was then:

"...required to physically take down my partner for the training using martial arts techniques. This included rolling on top of each other on the floor putting each other in positions of restraint and then handcuffing on the floor. I was partnered up with Sergeant Amber CARR who I estimate weighed approximately 70 kg. This training went the entire day and was physically strenuous, tiring and physical."

1. The respondent conceded liability in relation to the appellant's injury, and made relevant payments to the appellant for weekly benefits compensation and for medical expenses pursuant to s 60 of the Workers Compensation Act 1987 (the 1987 Act), until it issued a notice pursuant to s 78 of the 1998 Act dated 14 June 2023 (found at page 20 of the ARD), denying ongoing liability in this regard and advising:

"Although we acknowledge that you sustained an injury during your employment, EML do not consider you to currently have an ongoing work-related condition based on the information provided by Dr Anthony Smith, as the work-related injury has resolved."

1. The appellant subsequently (by a letter from her solicitors to the respondent's insurer dated 20 February 2024 - found at page 32 of the ARD) claimed compensation from the respondent in relation to her permanent impairment and her pain and suffering as a result of the injury, in accordance with ss 66 and 67 of the 1987 Act. She relied in this regard upon an opinion from Dr Bodel, in the doctor's report dated 29 January 2024 (found at page 45 of the ARD), that she had sustained 11% permanent impairment as a result of the injury.
2. The respondent issued a further notice pursuant to s 78 of the 1998 Act dated 29 May 2024 (found at page 39 of the ARD), in which it advised that it:

"...maintains its previous dispute (section 78) of 14 June 2023 and (section 287A) 5 July 2023 for any entitlement for weekly compensation payments under section 33 and medical treatment expenses under section 60 of the Workers Compensation Act 1987...It follows, that we dispute entitlement for you to claim lump sum compensation with respect to left hip and/or lower back pursuant to sections 66 and 67 of the Workers Compensation Act 1987."

1. As a result, the appellant lodged the ARD with the Personal Injury Commission (Commission) on 13 January 2025. The ARD claimed:

(a) ongoing weekly benefits compensation from 10 August 2023;

(b) payment of various medical expenses of the appellant's pursuant to s 60 of the 1987 Act;

(c) lump sum compensation pursuant to s 66 of the 1987 Act in relation to 11% permanent impairment, and

(d) lump sum compensation pursuant to s 67 of the 1987 Act in relation to pain and suffering.

1. The ARD became before Member Homan from the Commission, who successfully conciliated the appellant's claims in the ARD and issued a Certificate of Determination (COD) with the consent of the parties on 26 February 2025.
2. The appellant's claims for weekly benefits compensation and for payment of medical expenses pursuant to s 60 of the 1987 Act were resolved by the COD. The COD also acknowledged the respondent's consent for the level of the appellant's permanent impairment in relation to both her lumbar spine and her left lower extremity (hip) to be referred to medical assessment, as the respondent did not dispute injury in this regard.
3. The relevant referral to medical assessment was made by the Commission's 26 February 2025 direction, which resulted in the MAC being issued by the Medical Assessor on

1. The Appeal Panel has conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with Procedural Direction PIC7.
2. As a result of that preliminary review, the Appeal Panel determined that it was not necessary for the worker to undergo a further medical examination at this stage, because it possessed sufficient information in the material before it for it to be able to decide the Appeal.

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:

(a) the ARD and its attachments, and

(b) the respondent's Reply (Reply) and its attachments.

1. The parts of the MAC that are relevant to the Appeal are set out below. It is unnecessary however to refer to the MAC in more detail, given the specific grounds of appeal relied on by the appellant, in accordance with her submissions.
2. The Medical Assessor takes a brief history of the appellant's 29 November 2022 injury, and her subsequent treatment for her back and left hip conditions. He notes that in June 2024,

Dr Qurashi recommended that she undergo a left hip replacement (see the doctor's report dated 5 June 2024 - found at page 69 of the ARD), and he also notes that that surgery was to be undertaken on 22 April 2025 (one month and one day after his assessment of her). 3. He records:

(a) the appellant rated her current left hip pain as "a nine out of ten and constant";

(b) the appellant denied any problems with her left hip prior to 29 November 2022;

(c) the appellant remained on reduced hours employment duties "mostly due to the left hip";

(d) the appellant had a normal gait, and

(e) on examination, the appellant's left hip "had a smooth passive motion with reported pain in the groin on internal rotation of the hip".

1. His diagnosis in relation to the appellant's left hip is:

"Left hip strain, labral tear, aggravation of degenerative arthritis. An MRI of the left hip 18 January 2023 revealed mild OA changes of the left hip, a complex tear of the anterior superior labrum with degenerative wear of the superolateral labrum. An X-ray 21 March 2024 revealed severe left hip arthritis. Ms Daley was seen by Dr Qurashi, Hip Surgeon, and treatments were conservative. More recently Dr Qurashi recommended surgical treatment for a total hip replacement. Surgery is scheduled for 22 April 2025. Ms Daley reported persistent left hip pain. The physical examination revealed a loss of active motion...The history is consistent with the physical examination findings and is consistent with the documentation provided. The diagnosis of injuries is consistent with the mechanism of injury and is consistent with the current status of the condition."

1. At paragraph 8 in the MAC, the Medical Assessor answers questions as follows:

"b. Have all body parts/systems stabilised/reached maximum medical improvement? NO

c. If not, please list those injuries not yet stable/at maximum medical improvement: Left Hip

d. If stabilisation/maximum medical improvement, of any or all injuries has not been reached, when, in your opinion, will this occur? Ms Daley is scheduled for a left total hip replacement 22 April 2025. I expect MMI approximately 6 months after the surgery if all goes well."

1. Nevertheless, the Medical Assessor proceeds to assess the appellant's permanent impairment, finding:

(a) 0% permanent impairment in relation to the appellant's lumbar spine - a DRE category I assessment - as he found no guarding, no asymmetrical loss of motion, and no radicular signs or symptoms;

(b) 10% permanent impairment in relation to the appellant's left lower extremity (hip);

(c) a 50% deduction (pursuant to s 323 of the 1998 Act) in relation to the assessed impairment to the appellant's left lower extremity (hip) - to take into account the appellant's pre-existing left hip arthritis, and

(d) a final permanent impairment assessment of 5%.

1. Both parties made written submissions. They are not repeated in full, but have been fully considered by the Appeal Panel.
2. In summary, the appellant submits that the Medical Assessor's assessment was made on the basis of incorrect criteria as he misapplied the Guidelines, particularly cls 1.15 and 1.16. He should not have assessed her permanent impairment as she was scheduled to have left hip replacement surgery. He should have deferred the assessment. She submits:

"The consequences of the Medical Assessor's non-compliance are not simply academic, as a medical assessment of the Appellant will have to be undertaken subsequent to the hip replacement. Rather, the Medical Assessor's non-compliance has meant that the assessment undertaken pursuant to section 323 was also erroneous, and premature, because any consideration of the applicability of section 323 could not be undertaken until the final WPI in respect of the injury was assessed [emphasis in original]."

1. The appellant quotes from Cole v Wenaline Pty Limited [2010] NSWSC 78 (Cole) and Ryder v Sundance Bakehouse [2015] NSWSC 526 (Ryder) to submit that the Medical Assessor (in considering an impairment deduction pursuant to s 323 of the 1998 Act) "did not address whether the proportion of the final assessed impairment was actually due to the pre-existing abnormality i.e. whether the pre-existing abnormality actually made a difference to the outcome in terms of the degree of impairment". The Medical Assessor could not know what the appellant's final level of permanent impairment would be (following her left hip replacement surgery) and therefore could also not know "what level of contribution the underlying issues may have had to the ultimately assessed impairment".
2. In reply, the respondent concedes:

"The Respondent does not dispute that if the Appellant is to undergo further surgery in the form on [sic] total hip replacement, the permanent impairment may possibly increase following the stabilisation of the condition following the surgery. However, having been aware that the Appellant is to undergo this surgery, with all due respect, the Appellant ought to have advised the Respondent and the Personal Injury Commission in regard to same without having proceeded with the current claim for permanent impairment and more importantly, the examination and assessment by the MA...The MA has in the circumstances, assessed the Appellant's left hip as presented to him on the date of the assessment/examination before the surgery took place. The Respondent does not dispute that the Appellant's condition of the left hip could substantially change following the surgery and, therefore, may not have reached maximum medical improvement (MMI) at this stage."

1. The respondent submits however that the appellant "does not appeal the assessment and decision of the MA in respect of the lumbar spine impairment", and that the 0% permanent impairment assessment in this regard should be confirmed.
2. The respondent also submits that the Medical Assessor's application of a 50% impairment deduction pursuant to s 323 of the 1998 Act was available to him on the evidence and fully explained by him. It submits:

"Although the Respondent accepts that the assessment was carried out despite the Appellant having to undergo a total hip replacement procedure, the claim is based on the applicant's current condition and the impairment has been assessed by the MA based on restrictions of movements. Further, this does not impact on the decision relating to deduction under section 323 of the 1998 Act for pre-existing condition."

1. In Campbelltown City Council v Vegan [2006] NSWCA 284, the Court of Appeal held that an 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.
2. 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 - that is those errors identified by a party in its submissions - see New South Wales Police Force v Registrar of the Workers Compensation Commission of New South Wales [2013] NSWSC 1792.
3. The Appeal Panel in this regard has to ensure that it does not disturb any unchallenged findings in the MAC. In Queanbeyan Racing Club Ltd v Burton [2021] NSWCA 304, Basten JA stated (at [35]):

"The Appeal Panel was correct in the present case to address the subject matter of the ground of appeal, set aside the medical assessment certificate and issue another certificate including the amended assessments and [emphasis in original] the original unchallenged assessment. In doing so it neither purported to reassess the unchallenged finding nor to adopt the medical assessor's reasoning with respect to that finding; neither course was part of its statutory function."

1. It is not strictly correct (as submitted by the respondent - see paragraph 28 above) to suggest that the appellant's submissions do not complain about the Medical Assessor's assessment of the permanent impairment in her lumbar spine. They in fact submit in general terms that no assessment should have been undertaken of her permanent impairment until after her left hip replacement, without differentiating between her back and her left hip. It is possible in this regard that the left hip replacement surgery may affect her lumbar spine.
2. Clause 1.15 of the Guidelines reads:

"Assessments are only to be conducted when the medical assessor considers that the degree of permanent impairment of the claimant is unlikely to improve further and has attained maximum medical improvement. This is considered to occur when the worker's condition is well stabilised and is unlikely to change substantially in the next year with or without medical treatment."

"If the medical assessor considers that the claimant's treatment has been inadequate and maximum medical improvement has not been achieved, the assessment should be deferred and comment made on the value of additional or different treatment and/or rehabilitation."

1. In the opinion of the Appeal Panel, the Medical Assessor has failed to comply with these Guidelines, and in fact acknowledges as such in the MAC when he specifically states that the appellant's left hip condition has not reached maximum medical improvement (see paragraph 22 above). The fact that he nevertheless assesses her permanent impairment is an application of incorrect criteria (that is, cls 1.15 and 1.16 of the Guidelines) and a demonstrable error. The error in this regard is readily apparent from the MAC as the lack of maximum medical improvement is specifically stated in the MAC. As Hoeben SCJ stated in Merza v Registrar of the Workers Compensation Commission and Anor [2006] NSWSC 939 (at [39]):

"I do not propose to, nor is it necessary, that I define what is 'demonstrable error' for the purposes of s 327 of the Act in an exhaustive way. It is sufficient for the purposes of this matter that I conclude that 'demonstrable error' is an error which is readily apparent from an examination of the medical assessment certificate and the document referring the matter to the AMS for assessment."

1. The respondent accepts (see paragraph 27 above) that the level of the appellant's permanent impairment in her left lower extremity (hip) "could substantially change" following her left hip replacement. The Appeal Panel agrees in this regard.
2. Once he became aware of the appellant's proposed imminent left hip replacement surgery, the Medical Assessor should have deferred his assessment in accordance with cl 1.16 of the Guidelines.
3. For these reasons, the Appeal Panel has determined that the MAC should be revoked, and a new medical assessment certificate regarding the level of the appellant's permanent impairment will need to be eventually issued. That new medical assessment certificate cannot of course however be issued at the moment. The Appeal Panel will therefore confine its certificate revoking the MAC to a certificate pursuant to cls 1.15 and 1.16 of the Guidelines, deferring the appellant's assessment of whole person impairment on the basis that maximum medical improvement has not been achieved, and will not be achieved until the appellant's condition has stabilised following her left hip replacement surgery on 22 April 2025.
4. The eventual new medical assessment certificate regarding the level of the appellant's permanent impairment can only follow a re-assessment of that impairment once her condition has stabilised following her left hip replacement surgery. It will be incumbent upon her to request the Commission to undertake this re-assessment once stabilisation has occurred.
5. The re-assessment can consider a permanent impairment assessment of the appellant's lumbar spine if there is evidence that her left hip replacement surgery has affected her lumbar spine so as to place her in a category other than DRE category I (as found by the Medical Assessor).
6. The re-assessment will however re-consider the deduction to be applied to the appellant's assessed permanent impairment pursuant to s 323 of the 1998 Act. In this regard, the Appeal Panel agrees with the appellant (see paragraph 26 above) that the deduction can only be calculated once a final assessment of permanent impairment has been made following maximum medical improvement being achieved. A deduction is only applicable if a previous injury, pre-existing condition or abnormality makes a difference to the outcome [emphasis added] of an assessment of permanent impairment. That outcome can only occur once maximum medical improvement has been achieved.
7. As Schmidt SCJ observed in Cole (at [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."

"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 judgement, knowledge and experience. Nevertheless, all stages of the statutory exercise must be undertaken in the light of the evidence and without the making of assumptions not provided for by the section."

1. Further, in Ryder, Campbell SCJ observed (at [45]):

"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 [emphasis in original] of impairment resulting from the work injury. If there is no difference in outcome, that is to say, if the degree [emphasis in original] 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 [emphasis in original] of impairment resulting from the work injury would not have been as great."

1. The Appeal Panel considers, in accordance with Cole and Ryder that a deduction pursuant to s 323 of the 1998 Act is unable to be calculated until evidence is available to allow a correct and final assessment of permanent impairment, and indeed until that assessment has been made. In the appellant's case, the Medical Assessor made a deduction pursuant to s 323 of the 1998 Act in circumstances where the evidence before him (and accepted by him) was that the appellant's left hip condition had not reached maximum medical improvement. He erred in nevertheless calculating permanent impairment, and a re-assessment of the appellant's permanent impairment is therefore required in due course. It will only be after that re-assessment that a deduction pursuant to s 323 of the 1998 Act can be considered. In attempting to calculate the deduction before maximum medical improvement had been achieved, the Medical Assessor also erred. He determined a deduction before he was entitled to determine an entitlement.

1. The MAC is revoked.
2. The appellant's permanent impairment will need to be re-assessed once her condition has stabilised following her left hip replacement surgery.
3. The appellant is granted leave in due course to approach the Commission for this re-assessment by providing it with medical records which confirm that she has reached maximum medical improvement following her left hip replacement surgery on 22 April 2025.
4. The Appeal Panel orders that a copy of this decision be provided to the Medical Assessor undertaking the eventual re-assessment.

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 Todd Gothelf and issues this new certificate as to the matters set out below:

In accordance with cls 1.15 and 1.16 of the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4th ed, 1 March 2021, an assessment of the applicant's whole person impairment is deferred on the basis that maximum medical improvement has not been achieved, and will not be achieved until her condition has stabilised and reached maximum medical improvement following her left hip replacement surgery on 22 April 2025.