1. On 3 September 2025 Coolamon Shire Council (the appellant) 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 a Medical Assessment Certificate (MAC) on 5 August 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 Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5).

1. Michelle Jane Bartholomew (the respondent worker) sustained an injury to the lumbar spine on 11 March 2020 in her employment as an administrative assistant with the appellant.
2. The respondent worker lodged an Application to Resolve a Dispute (ARD) in the Personal Injury Commission (Commission) dated 3 March 2025 in which she claimed lump sum compensation in respect of the injury to her lumbar spine.
3. The matter was referred to Dr Peter Honeyman, Medical Assessor, for assessment of whole person impairment (WPI) of the lumbar spine as a result of the injury on 11 March 2020.
4. The Medical Assessor examined the appellant on 30 June 2025 and assessed 25% WPI of the lumbar spine. He made a deduction of one tenth pursuant to s 323 of the 1998 Act which resulted in a total of 23% WPI in respect of the injury on 11 March 2020.

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.
2. As a result of that preliminary review, the Appeal Panel determined that it was not necessary for the respondent worker to undergo a further medical examination because there was sufficient information on which to make a determination.

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. They are not repeated in full but have been considered by the Appeal Panel.
2. The appellant's submissions include the following:

(a) ground 1: failure to adequately address the medical evidence in the proceedings related to the respondent worker's pre-existing lumbar spine injuries in assessing the impairment which resulted from the prior injuries, and the applicable deduction under s 323 of the 1998 Act;

(b) the respondent worker suffered two prior injuries to her lumbar spine in November 1998 and on 8 May 2001. After the second injury, the respondent worker underwent an L5/S1 posterior decompression and lumbar interbody fusion procedure performed by Dr Sekhon on 31 July 2003;

(c) in the MAC, the Medical Assessor recorded a brief history of the respondent worker's pre-existing lumbar spine injury and stated "twenty years ago she had a fusion of L5/S1. After this surgery she was pain free. The original accident happened while she was doing kitchen services and she lifted a patient in a hospital. She was assessed under the Table of Disabilities";

(d) the Medical Assessor did not refer to any radiological evidence prior to

16 March 2020, despite the fact the ARD included an MRI report of the lumbar spine dated 8 January 20037 and CT reports dated 16 November 1998 and

20 June 2001;

(e) the Medical Assessor acknowledged that Dr Negus "notes the risk of degenerative disease above any fusions" and "reduces DRE values by 1/10". The Medical Assessor did not acknowledge (in any great detail) Dr Negus' reasons for making a one tenth deduction;

(f) the Medical Assessor acknowledged Dr Powell's opinion that the respondent worker "had developed adjacent segment disease which is a well-accepted sequelae of spinal fusion" and his application of a two thirds deduction "due to pre-existing disease";

(g) the Medical Assessor failed to adequately engage with the reasoning of Dr Powell who justified his deduction by referring to the "investigations performed at the time of the incident clearly established the presence of advanced degenerative pathology at the L4/5 level which represented adjacent segment disease";

(h) Dr Powell explained that the mechanism of the subject injury on 11 March 2020, "was at the relatively minor end of the spectrum" and was "sufficient to have caused a musculoligamentous injury and aggravation of some underlying degenerative pathology, though in itself would not normally be expected to result in a spinal fusion";

(i) the Medical Assessor had before him several reports which addressed the respondent worker's previous lumbar spine injury and the resultant impairment. There was evidence related to the respondent worker's previous injury and the resultant permanent impairment from Dr English (5 April 2004), Associate Professor Sekhon (15 April 2004), Dr Le Leu (10 September 2004), Dr Mansor and Dr Cousins (29 February 2005), and the GP clinical records dated

1 May 2007, 22 September 2012,10 September 2013, 16 April 2014,

27 May 2014, 30 September 2014, 18 June 2019 and 11 October 2019;

(j) in this case, the Medical Assessor had clear evidence related to the "actual consequences" of the respondent worker's previous injury which had resulted in a L5/S1 fusion procedure performed in 2003;

(k) the Medical Assessor failed to refer to the substance of the extensive evidence which addressed the extent of the previous injury and the resultant impairment. The Medical Assessor did not explain why the opinion of Dr Powell was not accepted or preferred, nor did he refer to the medical evidence related to the respondent worker's condition after the previous injury, including the assessment of permanent impairment made by Dr Le Leu in 2004. It was not apparent from the MAC if the Medical Assessor reviewed or considered Dr Le Leu's report which would be one of the most probative pieces of evidence of the "actual consequences of the earlier injury";

(l) the Medical Assessor's failure to consider the medical evidence before him, and "explain, even if briefly, why it was not accepted or not preferred" amounts to a demonstrable error;

(m) ground 2: application of the one tenth deduction under s 323(2) of the 1998 Act, in circumstances where this conclusion was at odds with the medical evidence and/or where it was not difficult or costly for the Medical Assessor to assess the deduction for the proportion of the impairment due to the previous injury;

(n) the Medical Assessor fell into demonstrable error and/or applied in correct criteria in his assessment of the deduction for the respondent worker's previous injury and in his reliance on the one tenth deduction under s 323(2) of the 1998 Act;

(o) it is not in issue that the respondent worker's injury on 11 March 2020 resulted from an acute lifting incident, and that she has experienced radiculopathy which has required ongoing management;

(p) the Medical Assessor's observation the respondent worker had "20 years without symptoms after her earlier injury" was inconsistent with the medical evidence before him which showed the respondent worker continued to experience symptoms from 2012 to 2019, after her injury on 8 May 2001;

(q) the Medical Assessor considered incorrect criteria in his decision to apply the one tenth deduction. The evidence above demonstrated the extent of the respondent worker's previous injury and the impairment which resulted from this injury;

(r) consistent with s 323(2) of the 1998 Act, where there is an absence of evidence or the extent of the deduction is 'difficult or costly to determine', a Medical Assessor is entitled to assume a one-tenth deduction, unless the assumption was "at odds with the available evidence";

(s) there was no "absence of evidence" which would justify application of the one tenth assumed deduction in this case. There was sufficient evidence for the Medical Assessor to determine the extent of permanent impairment which resulted from the prior injury. The Medical Assessor failed to engage with this evidence and did not explain why it was not accepted or preferred. In the circumstances, it was not permissible for the Medical Assessor to apply a one tenth deduction for the worker's pre-existing lumbar spine pathology;

(t) the Medical Assessor had ample evidence before him by which to assess the deduction. The evidence showcased the previous injuries and their consequence including the requirement for lumbar spine fusion surgery at L5/S1. The clinical records disclosed the respondent worker experienced ongoing back and referred leg pain up to approximately 2019. The fact the Medical Assessor knew the respondent worker underwent the fusion surgery at L5/S1 alone enabled him to make an assessment of permanent impairment resulting from the earlier injury. The report of Dr Le Leu in 2004, provided an assessment of the impairment which resulted from the previous injury, and indicated the worker's previous injury resulted in an impairment rating of DRE Lumbar category 4 (23% WPI);

(u) there was no absence of medical evidence, and it was not too difficult or costly for the Medical Assessor to assess the deduction for the proportion of the impairment due to the previous injury;

(v) the Medical Assessor's assumption of a one-tenth deduction under s 323(2) was at odds with the available evidence dealing with the prior injury which resulted in the fusion surgery at L5/S1;

(w) the Medical Assessor should have assessed the permanent impairment to the lumbar spine resulting from the earlier injuries and, by reference to the clinical records, should have seen the respondent worker had ongoing complaints of back and leg pain after the previous injury as late as 2019;

(x) accordingly, the Medical Assessor made a demonstrable error and/or applied incorrect criteria in his assessment of the deduction applicable for the previous lumbar spine injury, and in his reliance on the one tenth assumed deduction under s 323(2) of the 1998 Act (which was at odds with the evidence before him), and

(y) the MAC should be revoked and the respondent worker re-examined or the Appeal Panel determine the applicable deduction on the papers.

1. The respondent's submissions include the following:

(a) ground one: failure to adequately address medical evidence. At issue is the extent of the deduction to be applied as a result of the respondent worker's pre-existing disability;

(b) the respondent worker suffered earlier injuries to her back in 1998 and 2001. Those injuries were treated successfully by an interbody fusion performed on the 31st of July 2003;

(c) the clinical records of the medical centre provide a useful chronology - the respondent worker attended her doctor and made complaint of back pain on one occasion in 2007, on about five occasions between 2012 and 2013, and then on two further occasions in 2019. The respondent worker made no other complaint of back pain during other visits to the same medical centre over that period;

(d) the difficulty in relying upon the entries in the medical records is that they do not provide a complete history or picture of the complaint for which the respondent worker was seeking medical advice at the time. In Cruceeanu v VIX Technology (Aust) Ltd [2019] NSW WCC 235, Arbitrator Sweeney said (at [67]): "On several occasions in recent years, the Court of Appeal has cautioned against the use of medical records and the histories contained in medical reports to undermine the credibility of a witness.(See): Davis v Council of the City of Wagga Wagga [2004] NSWCA 34 (26 February 2004); Fitzgibbon v Waterways Authority and Others [2003] NSWCA 294 (3 December 2003); and Mason v Demasi [2009] NSWCA 227 (31 July 2009)";

(e) these cases suggest that a tribunal would be wary of preferring entries in the clinical records to the evidence of witnesses. They also emphasise that the primary function of medical records is to facilitate treatment and not as an unerring record of the medical history;

(f) given that the earlier injury occurred some 20 years before the subject accident, it is particularly difficult to assess what impact that earlier injury had in relation to the respondent worker's current disability. A limited number of visits to a doctor with complaint of back pain over a 20 - year period for the respondent worker who has always been involved in heavy manual work might be said to be typical, even without the earlier injury;

(g) the question of the pre-existing disability suffered by the respondent worker was an issue of which the Medical Assessor was aware. The Medical Assessor noted the opinion of both of Dr Negus and Dr Powell in respect to that issue. Given the comments of Arbitrator Sweeney, it is quite understandable that the Medical Assessor would have difficulty determining the extent of the deduction that would be appropriate in the circumstances. The application of s 323(2) of the 1998 Act was not only open to the Medical Assessor in the circumstances, but appropriate;

(h) in Wingfoot v Kosak [2013] HCA 43, the High Court affirmed that an administrative decision-maker is not to be critiqued "minutely and finely with an eye keenly attuned to the perception of error". When evaluating the rationale of the Medical Assessor, it must be borne in mind that "the reasons of an administrative decision-maker are meant to inform and not be scrutinized upon over-zealous judicial review by seeking to discern whether some inadequacy may be gleaned from the way in which the reasons are expressed." (See Minister for Immigration and Ethnic Affairs v Wu Shan Liang (1996) 185 CLR 259; [1996] HCA 6);

(i) in Insurance Australia Group Limited trading as NRMA Insurance v Keene [2021] NSWCA 287. The court stated the following: "The standard of reasons required of a medical assessor is different from the standard required of a court. It is borne firmly in mind that Dr Meakin was a qualified medical specialist, and ultimately his certificate reflected his own professional judgement as to the whole person impairment of Mr. Kane and whether it had been caused by the motor vehicle accident";

(j) imposing a requirement to communicate every step of his clinical observation and reasons would set an overwhelming burden. Interpreting the obligation on a Medical Assessor in such a manner, considering the decision-making framework and the statutory objectives outlined in the 1998 Act, would undermine the intended purpose of the Guidelines and the overall assessment of the scheme;

(k) ground two - the submissions in respect of appeal ground 1 are repeated and adopted;

(l) the respondent worker suffered a significant injury 20 years earlier. There were a handful of complaints in the medical records of the respondent worker over the succeeding period, but little other guidance for the Medical Assessor. The last medical record recorded by her treating doctor, prior to the subject injury, reports a complaint of vertigos and makes no mention of back pain, and

(m) for the reasons set out above, it is submitted that this is the very type of case that attracts the attention of s 323(2). It was not only open to the Medical Assessor to avail himself of that provision, but it was appropriate that he do so.

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.
3. The Appeal Panel reviewed the MAC and the evidence in this matter.

Ground 1 - s 323 Deduction - Failure to address the evidence

1. In the MAC on page 2 under "Details of any previous or subsequent accidents, injuries or condition, the Medical Assessor wrote:

"Twenty years ago she had a fusion of L5/S1. After this surgery she was pain free. The original accident happened while she was doing kitchen services and she lifted a heavy patient in a hospital. She was assessed under the Table of Disabilities."

1. In the MAC on page 3, under "Details and dates of special investigations", the Medical Assessor wrote:

"18/9/24 Dr J Negus IME: notes the risk of degenerative disease above any fusions. Reduces DRE values by 1/10.

20/11/24 Dr Leu IME: This was listed by the insurer but not provided in the notes (??)

26/11/24 Dr Richard Powell IME: noted she had developed adjacent segment disease which is a well-accepted sequalae of spinal fusion. Her rates DRE 4 but due to preexisting disease, reduces by 2/3rds."

1. The Medical Assessor noted that the respondent worker suffered an acute low back injury that required bilateral facetectomies and fusion at L4/5 and has ongoing bilateral radiculopathy where a spinal stimulator has provided partial relief.
2. At Part 8 of the MAC, the Medical Assessor wrote:

"e. Is any proportion of loss of efficient use or impairment or whole person

impairment, due to a previous injury, pre-existing condition or abnormality?

f. If so, please indicate which body part/system is affected by the previous injury,

1. Under "Reasons for Assessment" at Part 10 c the Medical Assessor wrote:

"Drs Negus and Powell agree on rating the fusion operation. And agree the lifting at work did cause the injury. They also agree the previous surgery predisposed to the level above being affected, but disagree on the deduction. I am in agreement and deduct 1/10th."

1. At Part 11 of the MAC, the Medical Assessor wrote:

"a. In my opinion the worker suffers from the following relevant previous injuries, pre-existing conditions or abnormalities: She has a previous fusion at L5 S1 which predisposes degenerative changes at the joint above.

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) She had near 20 years without symptoms following the initial injury.

(ii) She had an acute lifting injury that has resulted in this injury

(iii) She has ongoing significant radiculopathy that requires ongoing management.

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. Dr Jonathan Negus, consultant orthopaedic surgeon, in a report dated 18 September 2024 assessed 24% WPI of the lumbar spine and applied a one tenth deduction for the pre-existing condition. He noted that the respondent worker previously had a L5/S1 decompressive laminectomy and posterior lumbar interbody fusion with reduction of spondylolisthesis on 1 July 2003 and "back pain present since fusion, but no leg pain prior to current incident".
2. Dr Richard Powell, consultant orthopaedic surgeon, in a report dated 26 November 2024, assessed the respondent worker as having 24% WPI. He noted that there was clear evidence of significant pre-existing pathology and considered that the mechanism of injury was at the "relatively minor end of the spectrum with the involvement of bending, lifting and twisting manoeuvres". Dr Powell wrote:

"It was considered sufficient to have caused a musculoligamentous injury and aggravation of some underlying degenerative pathology, though in itself would not normally be expected to result in a spinal injury....

The investigations performed at the time of the incident clearly established the presence of advanced degenerative pathology at the L4/5 level which represented adjacent segment disease, which was primarily related to the pre-existing condition at LS/S1 which in turn was developmental and degenerative in nature.

In consideration of all these factors, I would make a deduction of two thirds of the above figure to reflect the extent of the pre-existing condition. This results in 8% whole person impairment."

1. In a report dated 15 April 2004, Associate Professor Lali Sekhon, treating neurosurgeon, reported the respondent worker continued to have pain in both buttocks and down the backs of her legs.
2. In a report dated 10 September 2004, Dr Leon Le Leu, consultant occupational physician, reported that the respondent worker experienced pain going into the right buttock and down the right leg to the knee. Dr Le Leu wrote:

"Her situation is best covered by a higher level of DRE lumbar category IV which gives 23% impairment. This can be translated to a pre 1 January, 2002 impairment using the conversion factor on page 427 of Guides to the Evaluation of Permanent Impairment, Fifth Edition. This gives a back impairment of 30%. At her age it would be reasonable to attribute 15% of that impairment to natural causes giving 26% back impairment."

1. In a report dated 5 April 2004, Dr Peter English, general practitioner, noted that he was putting the respondent worker back on Oxycontin 20 mgs b.d. as Tramal 200mgs SR b.d. did not adequately control her pain and also made her quite nauseous.
2. On 29 February 2005, Dr Marzida Mansor and Professor Cousins of the Pain Management and Research Centre Royal North Shore Hospital reported the worker suffered ongoing pain radiating to her right knee and associated with a tingling sensation in her right foot.
3. The clinical notes of Coolamon Regional Medical Centre contained the following entries:

(a) On 1 May 2007: Dr English recorded the reason for contact was 'pain - back - lumbosacral';

(b) on 22 September 2012: Dr English recorded the reason for contact was 'sciatica'. The corresponding handwritten written record stated the worker had 'done something to her back' and was experiencing symptoms in her right buttock and leg;

(c) on 10 September 2013: Dr Amir recorded the reason for contact was 'back pain';

(d) on 16 April 2014: Dr Amir recorded the reason for contact was 'back pain';

(e) on 27 May 2014: Dr Amir recorded the reason for contact was 'back pain';

(f) on 30 September 2014: Dr English recorded the reason for contact was 'back injury';

(g) on 18 June 2019: Dr Amir recorded the worker had developed leg pain arthritic pain groin pain rt sided started 3 months ago have bone scan and X-ray facet joint arthritis. Dr Amir prescribed Lyrica for 'neuropathic pain', and

(h) on 11 October 2019: Dr Xu recorded the worker attended for a review and repeat script and her 'lower back pain ontrolled (sic) with current medications' initially started on the left side now both hips pain with radiation to groins. On examination he noted that there was localised tenderness in the right lower back and "range of lumbar spine movement in normal range."

1. In her statement dated 18 February 2025 that respondent worker stated that she began working with Coolamon Ganmain Hospital as a domestic service worker in 1986 and did not have any significant back pain until November 1998 when she hurt her back helping a nurse lift a bed. She said that her back injury was made worse on 8 May 2001 when she slipped in a puddle at work.
2. The respondent worker wrote:

"6. As a result of my injuries, I was treated by my family doctor, Dr English ...I was treated by various specialists and ultimately referred to Dr Lali Sekhon. A neurosurgeon. Dr Sekhon operated on my back on 31 July 2003 when he performed an L5/S1 Decompressive Laminectomy and Posterior Lumbar Interbody Fusion.

7. For a couple of years after the accident, I suffered significant pain. I had extensive rehabilitation and medical treatment, and I consumed a large amount of pain killers.

8. With treatment, my injury gradually improved. I was able to stop taking medication after about 3 years and I found that a regular exercise regime helped.

9. I returned to work with the hospital doing light duties about 12 months after the accident but ultimately my employment was terminated.

10. In 2010, I started working for my son's takeaway business which traded as Bartys Takeaway in Coolamon. I worked full time, and I assisted with customer service, cooking and cleaning. I didn't have any back pain when I was working and I found that as long as I kept myself fit, I did not have any problems. I didn't have treatment for back pain during that period of time.

11. In 2018 I resigned my job with Bartys. I had found a better job working with Allawah Community Centre which was part of Coolamon Shire Council, where I worked as an administrative assistant. I initially worked part time but I increased my hours to become a full time employee."

1. The appellant submits that the Medical Assessor failed to adequately address the medical evidence in the proceedings related to the respondent worker's pre-existing lumbar spine injuries in assessing the impairment which resulted from the prior injuries, and the applicable deduction under s 323.
2. The Appeal Panel accepts that the Medical Assessor failed to adequately address the medical evidence in this matter and, in particular, the evidence concerning the respondent worker's earlier injuries to her lumbar spine in 1998 and May 2001, the surgery on

31 July 2003 and complaints of back pain after that surgery. The Medical Assessor in making his assessment relied on a history of the respondent worker being pain free after the surgery in 2003. This history was not supported by the evidence which clearly showed that the respondent worker had significant levels of pain following the surgery in 2003 for several years and then attended her doctor complaining of back pain on one occasion in 2007, on about five occasions between 2012 and 2013, and then on two further occasions in 2019. 3. The Medical Assessor, at Part 11 b. of the MAC, stated that he had taken into account when assessing "the previous injury, pre-existing condition or abnormality direct contribution" to the whole person impairment that results from the injury, that the respondent worker "had near 20 years without symptoms following the initial injury". The Appeal Panel is satisfied that this is an error and that the respondent worker was not symptom free after the surgery in 2003. 4. The deduction made by the Medical Assessor under s 323 was based in part on a history that was incorrect. The Appeal Panel is satisfied that the Medical Assessor made a demonstrable error as he was unaware of significant factual matters, that is, the occurrence of symptoms in the lumbar spine after the surgery in 2003. 5. This ground of appeal is made out.

Ground 2 - deduction of one-tenth at odds with the evidence

1. The appellant submits that the application of the one-tenth deduction under s 323(2) of the 1998 Act was:

(a) at odds with the medical evidence, and

(b) was not difficult or costly for the Medical Assessor to assess the deduction for the proportion of the impairment due to the previous injury.

1. As noted above, the evidence demonstrates that the respondent worker was not "symptom free" after the surgery to her lumbar spine in 2003.
2. The Appeal Panel noted that the Medical Assessor only referred to the radiological evidence from MRI scans in 2020 and 2021 and not to the earlier report of the MRI scan undertaken in 2002.
3. The report of MRI Lumbar spine of Dr A Scott, radiologist, dated 26 March 2002 found:

"There is quite marked hypertrophic degenerative arthropathy in the facet joints, which is especially marked at L4/5 level". Dr Scott concluded: "Facet joint degenerative arthritis is quite marked at the L4/5 level bilaterally."

1. In the report of MRI Lumbar spine of Dr Hamish McKay, radiologist, dated 18 March 2020 concluded:

"The most significant finding is asymmetrical but quite marked degenerative change of the facet joints at L4/5 (ie level above fusion), with facet joints osteophytes contributing to moderate to severe left L4/5 foraminal stenosis and compression of the exiting left L4 nerve root."

1. The MRI scan of 26 March 2002 is evidence of a pre-existing condition, namely, marked arthritis in the facet joints at L4/5. This was not considered by the Medical Assessor in his assessment of what proportion of the impairment was due to the pre-existing condition.
2. Taking into account the evidence in this matter and, in particular, the radiological investigations, the Appeal Panel is satisfied that the deduction of one-tenth was at odds with the evidence. The Appeal Panel further considers that a deduction for pre-existing injury and condition was not difficult or costly for the Medical Assessor to assess because there was radiological evidence available concerning the pre-existing injury as well as a number of medical reports of treating doctors and the clinical notes of the general practitioner.
3. This ground of appeal is made out.

1. Paragraphs 1.27 - 1.28 of the Guidelines provides that:

"The degree of permanent impairment resulting from pre-existing impairments should not be included in the final calculation of permanent impairment if those impairments are not related to the compensable injury. The assessor needs to take account of all available evidence to calculate the degree of permanent impairment that pre-existed the injury.

In assessing the degree of permanent impairment resulting from the compensable injury/condition, the assessor is to indicate the degree of impairment due to any previous injury, pre-existing condition or abnormality. This proportion is known as 'the deductible proportion' and should be deducted from the degree of permanent impairment determined by the assessor. For the injury being assessed, the deduction is 1/10th of the assessed impairment, unless that is at odds with the available evidence."

1. Paragraph1.6(a) of the Guidelines provides that:

"Assessing permanent impairment involves clinical assessment of the claimant as they present on the day of the assessment taking into account the claimant's relevant medical history and all available relevant medical information ..."

"(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.

Note. So if the degree of permanent impairment is assessed as 30% and subsection (2) operates to require a 10% reduction in that impairment to be assumed, the degree of permanent impairment is reduced from 30% to 27% (a reduction of 10%).

(3) The reference in subsection (2) to medical evidence is a reference to medical evidence accepted or preferred by the medical assessor in connection with the medical assessment of the matter.

(4) The WorkCover Guidelines may make provision for or with respect to the determination of the deduction required by this section."

1. In Cole v Wenaline Pty Limited [2010] NSWSC 78 (Cole). Schmidt J said:

"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.

31 ...That is a matter of fact to be assessed on the evidence led in each case".

1. In Ryder v Sundance Bakehouse [2015] NSWSC 526 the operation of s 323 was explained by reference to Southwell v Qantas Airways Limited [2024] NSWSC 497 (Southwell) at [50] and earlier authority. The Appeal Panel accepts that enquiries should be made as to what the extent of the resulting impairment is, whether the pre-existing condition contributed to the impairment and if it did what proportion of the impairment was due to the pre-existing condition.
2. The Appeal Panel notes that as explained in Southwell at [51]-[58] this requires a consideration of whether the pre-existing condition contributed causally to the impairment suffered as the result of the workplace injury, as well as whether a portion or part of that level of impairment was due to the pre-existing condition, rather than the workplace injury.
3. Even if before a workplace injury a pre-existing condition was asymptomatic, a deduction will be required if some portion of the level of impairment following injury was due to the pre-existing condition, rather than to the injury: Vitaz v Westform (NSW) Pty Ltd [2011] NSWCA 254 at [43].
4. Having found error that the Medical Assessor erred in the making of a deduction pursuant to s 323 of the 1998 Act in relation to the lumbar spine, the Appeal Panel must consider what deduction should be made for the pre-existing condition in the lumbar spine.
5. There is no issue that the respondent worker had a pre-existing injury to her lumbar spine. The Appeal Panel must determine the extent that the level of impairment following the subject injury was due to the earlier pre-existing injury and condition.
6. The Appeal Panel notes that the respondent worker stated that she was lifting at least 15kg when she sustained the injury to her lumbar spine on 11 March 2020. The Appeal Panel considers that this is quite a significant weight for a woman of the respondent worker's build to lift. This weight was not taken into account by Dr Powell, when he considered the mechanism of injury. The respondent worker had an acute onset of symptoms with radiation of pain down her right leg in the injury on 11 March 2020.
7. The Appeal Panel referred to the radiological investigations noted above. The MRI scan of 26 March 2002 reported that facet joint degenerative arthrosis was quite marked at L4/5 level bilaterally. The Appeal Panel concludes on the basis of that scan that the respondent worker had marked degenerative disease (arthritis) at L4/5 in 2002. This was most probably a constitutional condition. The Appeal Panel considers that the degenerative changes at L4/5 would then have been aggravated by the L5/S1 fusion performed in 2003 leading to the development of adjacent segment disease at L4/5.
8. The Appeal Panel considered the clinical notes of the general practitioners. The Appeal Panel accepts that there were some complaints of back pain after pain over the years, but the respondent worker managed to work in her son's takeaway food business and then with the appellant. The respondent worker passed the Pre-Employment Functional Assessment conducted by Ms Moloney of Rehab Co on 27 March 2019.
9. The Appeal Panel considered that taking into account the respondent worker's prior injuries to the lumbar spine in 1998 and 2000, the degenerative arthritic changes at L4/5 shown on the MRI scan of 26 March 2002, the L5/S1 posterior decompression and lumbar interbody fusion procedure performed on 31 July 2003 and history of back problems, a deduction of four tenths should be made pursuant to s 323 of the 1998 Act in respect of the impairment of the lumbar spine.
10. The Appeal Panel therefore assesses 25% WPI of the lumbar spine and deducts four tenths which results in 15% WPI as a result of the injury on 11 March 2020.
11. For these reasons, the Appeal Panel has determined that the MAC issued on 5 August 2025 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

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 Dr Peter Honeyman and issues this new Medical Assessment Certificate as to the matters set out in the Table below:

Chapter, page and paragraph number in NSW workers compensation guidelines

Chapter, page, paragraph, figure and table numbers in AMA 5 Guides

Proportion of permanent impairment due to pre-existing injury, abnormality or condition

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

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