State of New South Wales (Hunter New England Local Health District)

WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; review of Medical Assessment Certificate (MAC); assessment by Medical Assessor (MA) of 14% whole person impairment (WPI) of right lower extremity (knee); appeal on basis of error in application of Table 16-10 of American Medical Association Guides to the Evaluation of Permanent Impairment, 5th ed (AMA 5) in not addressing use of amitriptyline and its effects on sensory deficits; no requirement for MA to assess nature and extent of sensory deficits with or without use of amitriptyline for purpose of classifying sensory deficit; Appeal Panel agreed with Grade 2 rating; Appeal Panel found no failure to make an adjustment for effects of medication as amitriptyline was not a long term treatment and has not resulted in apparent substantial or total elimination of the permanent impairment; Held - MAC confirmed.

1. On 10 September 2025 Phillip Frost (the appellant) lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr David Lewington, a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on

27 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. The appellant sustained an injury to right lower extremity (knee) in the course of his employment as a carpenter with State of New South Wales (Hunter New England Local Health District) (the respondent) on 27 August 2021.
2. The appellant filed an Application to Resolve a Dispute (ARD) dated 10 December 2024.
3. In a Certificate of Determination - Consent Orders dated 10 February 2025 Member Cameron Burge remitted the matter to the President for referral to a Medical Assessor for assessment of permanent impairment as a result of injury to the right lower extremity (knee) on 27 August 2021.
4. The matter was referred to Dr David Lewington, Medical Assessor, for assessment of whole person impairment (WPI) of the right lower limb (knee).
5. The Medical Assessor examined the appellant on 25 August 2025.
6. The Medical Assessor assessed 14% WPI of the right lower extremity (knee) as a result of the injury on 27 August 2021.

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.

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 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 - error in the application of Grade 2 (as opposed to Grade 1) when applying Table 16-10 of AMA 5. At page 2, the Medical Assessor notes the appellant's use of Amitriptyline but otherwise makes no record of frequency of use, dosage or the appellant's history of symptom relief arising from the use of this medication;

(b) it is accepted the appellant does not meet the criteria for complete motor or sensory peripheral nerve loss, and, therefore assessment pursuant to Table

16-10 of AMA 5 is appropriate;

(c) the Medical Assessor erred by not addressing the appellant's use of Amitriptyline and its impact upon the nature and extent of his symptoms and sensory deficits. This omission impacts the classification and grading of the sensory deficit or pain assessed pursuant to Table 16-10 of AMA 5;

(d) the history obtained by the Medical Assessor is inadequate to meaningfully understand the nature and extent of the appellant's sensory deficits, both with and without the use of Amitriptyline_,_ for the purposes of classifying and grading the sensory deficit;

(e) with reference to Table 16-10, the history obtained by the Medical Assessor does not adequately or at all address the nature of the sensory deficits described for the purposes of classifying and grading the sensory deficit or pain;

(f) it is acknowledged that the "clinical judgement" of the Medical Assessor is to be utilised but this does not overcome the deficit in history or the failure to contemplate the benefits to the appellant from the use of medications;

(g) ground 2 - the Medical Assessor has erred by failing to make an adjustment for the effects of treatment, pursuant to cl 1.32 of the Guidelines. The Guidelines allow the Medical Assessor to adjust the percentage of impairment by 1%, 2% or 3% where the effect of long-term treatment results in a reduction or elimination of the appellant's permanent impairment;

(h) it was open to the Medical Assessor to apply cl 1.32 and appropriate for the Medical Assessor to do so, in circumstances where the evaluation of impairment pursuant to Table 16-10 of AMA 5 is compromised by the appellant's use of Amitriptyline;

(i) the appellant's use of Amitriptyline is solely to manage his sensory deficits resulting from peripheral nerve disorders and has not been considered by the Medical Assessor, pursuant to the method of assessment applied under Table 16-10 of AMA 5. In these circumstances it would have been appropriate for a Medical Assessor to make an adjustment for the use of this medication;

(j) clause 1.32 of the Guidelines does not apply for use of "...analgesics or anti-inflammatory medication for pain relief'. Amitriptyline is not an analgesic, and that this flows logically from page 482 of AMA5, which when providing guidance about the use of Table 16-10 of AMA5, states it is "... for pain that is due to nerve injury or disease that has been documented with objective physical findings or electrodiagnostic abnormalities. It is not to be used for the pain in the distribution of a nerve that has not been injured ...";

(k) the Medical Assessor accepts the appellant has sustained a nerve injury and the medication prescribed is precisely to alleviate symptoms from a nerve injury. This is clear and distinct from an analgesic used for generalised pain relief as contemplated by cl 1.32 of the Guidelines;

(l) an adjustment to impairment should be made utilising cl 1.32 of the Guidelines to accommodate and recognise the contribution to the alleviation of symptoms and impairment from the use of Amitriptyline;

(m) alternatively, the Medical Assessor Appeal Panel should consider the appropriate grading of the appellant's sensory deficits pursuant to Table 16-10 of AMA 5, excluding symptom relief from Amitriptyline, and

(n) this latter proposal is not practical or possible and, accordingly, an adjustment pursuant to cl 1.32 of the Guidelines as the appropriate method to adjust impairment for the alleviation of symptoms from medication usage.

1. The respondent's submissions include the following:

(a) essentially, the appellant contends the evidence and methodology in the ARD and Reply (Independent Medical Examiner (IME) reports of Prof Ghabrial and Dr Bentivoglio in particular) should have been preferred, noting that they produced some other result than that which the Medical Assessor reached. That is to say, the appellant is advocating for a particular (different) result, rather than demonstrating an error or the application of incorrect criteria in the MAC. The proper question to be asked is whether the Medical Assessor reached a sound and rationale finding with respect to his assessment of the right lower extremities (right knee);

(b) taking into consideration the meticulous history the Medical Assessor took of longstanding problems at the right knee impacting on the peripheral nerve impairment, he went to great lengths to explain his findings appropriately particularly at paragraph 10 (c) page 7 of the MAC;

(c) the Medical Assessor saw it fit to apply the criterion prescribed for the assessment of such injuries as stipulated in the Guidelines and AMA 5 which set out the criterion for calculating motion impairment of the right knee. The appellant assessment pursuant to Table 16-10 of AMA 5 is appropriate_;_

(d) there was no other means of assessing the right knee at the Medical Assessor's examination. There is no requirement for the Medical Assessor to take into consideration the implications or efficacy of medication to arrive at a sound assessment as per the criterion described above. Neither of the IMEs relied on upon by either party applied the correct criterion, and neither referenced the use of medications in explaining how they arrived at their varying assessments with respect to the sensory component of the assessment;

(e) whilst the appellant is critical of the Medical Assessor's methodology of assessment of the right lower extremity, it was open to the Medical Assessor to apply same, provided he gave a fair and reasonable consideration of the issues at play and supported same with an explanation. The Medical Assessor, in fact, sets out substantial information and material which ground his ultimate findings. The Medical Assessor was correct in not giving undue weight to the efficacy or lack thereof of Amitriptyline in arriving at 14% WPI for the right knee;

(f) the Medical Assessor explained his reasons satisfactorily. Essentially, the Medical Assessor preferred his approach when examining the appellant on the day, and it differed from that of the IMEs;

(g) the appellant's submissions criticise the Medical Assessor for failing to take an adequate history with respect of the appellant's use of Amitriptyline and how failing to do so may have impacted the overall assessment. However, an explanation has not been provided by the applicant to support his submission as to what the appropriate alternative criterion the Medical Assessor should have used. The use of Amitriptyline is a recent addition which has only become apparent due to a thorough taking of the history from the appellant by the Medical Assessor;

(h) the use of Amitriptyline had never previously been medication used by the appellant until very recently. This is evidenced by the absence of the mention of Amitriptyline in any of the evidence relied upon by either party which included the clinical material, both IME reports of Prof Ghabrial (dated 29 April 2024) and Dr Bentivoglio (dated 16 October 2024) and even the appellant's own statements as recent as 4 February 2025 and 26 May 2025;

(i) as such, the Medical Assessor simply could not give much, if any, weight for the very recent use of new medication being trialled by the appellant for what appears to be the very first time. The thorough history taking of the Medical Assessor is the reason we are aware that the appellant is taking Amitriptyline;

(j) due to the recency of the use of Amitriptyline by the appellant and the fact the appellant had not taken this medication on a long-term basis it was not open to the Medical Assessor to even apply any adjustment for the long-term effect of treatment as per the Guidelines;

(k) the Medical Assessor ultimately lays out the reasoning for the use of his discretion in determining the correct assessment criterion in calculating and noting the preferred criterion for the assessment of the right lower extremity (right knee), which was open to him in the Guidelines and AMA 5;

(l) the appeal amounts to simply a contention that the Medical Assessor has reached an opinion with which the appellant disagrees without any accompanying reasons is sufficient to displace it, and in whose place the appellant would prefer his own IME's opinion to be substituted;

(m) the Medical Assessor is required at law to explain his reasoning and has done so with respect to the right lower extremity (right knee). The appellant has offered a submission by way of a critique of the Medical Assessor, without providing supporting evidence, and

(n) the appellant has failed to show any "demonstrable error" nor the application of incorrect criterion on the face of the MAC. The MAC ought to be confirmed.

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 - The MAC contains demonstrable errors and the incorrect utilisation of the impairment assessment criteria in relation to the application of Grade 2 (as opposed to Grade 1) when applying Table 16-10 of AMA5

1. The appellant submits that the Medical Assessor erred by not addressing the appellant's use of Amitriptyline and its impact upon the nature and extent of his symptoms and sensory deficits. The appellant asserts that this omission impacts the classification and grading of the sensory deficit or pain assessed pursuant to Table 16-10 of AMA5.
2. Under "Present treatment" on page 2 of the MAC, the Medical Assessor wrote: "Panadol Amitriptyline".
3. Under "Social Activities/ADL" on page 3 of the MAC, the Medical Assessor wrote:

"Lives with his wife on a 40 acre property. He has difficulty negotiating up and down stairs or getting on and off of his tractor. He manages to do domestic tasks by pacing and modifying. He is no longer able to do the heavier tasks around the property and has sold his cattle. He uses a ride on mower to mow the lawns."

1. In the MAC under "Findings on physical examination" the Medical Assessor wrote:

"All range of movement testing the patient was advised to do their best but within their own limitations of pain and comfort levels.

There is 3 cm wasting of the right thigh compared to the left associated with reduced power in knee extension.

Range of movement of the right knee is 10° to 105° with normal movements of the left knee associated with minor crepitus.

There is subjective reduction in pinprick sensation in the distribution of the right femoral nerve.

1. Under "Details and dates of special investigations" the Medical Assessor referred to the studies including:

"iii. Nerve conduction studies in 2 March 2022: were reported to show a reduction of the right femoral compound muscle action potential, consistent with disuse atrophy. There was no evidence of a generalised or focal sensory nerve involvement or motor nerve dysfunction. The neurologist writes 'there is no electrophysiological evidence of a generalised or focal neuropathy including femoral (nerve)'. The neurologist goes on to write that there is no evidence of a generalised or focal 'myopathy, lumbar plexopathy, sciatic nerve lesion, lumbar radiculopathy, or other neuromuscular disease'.

iv. Repeat nerve conduction study conducted 27 October 2022: yielded no change in the findings. It was noted that the indication for repeat electrophysiological studies was "decreasing strength right leg. Hypersensitivity proximal to the patella. Previous nerve conduction studies (2 March 2022) normal."

1. Under "Summary of injuries and diagnoses" the Medical Assessor wrote:

"On 27 August 2021, hyper flexion injury to right knee associated with damage to the medial femoral condyle, tear to the quadriceps distal rectus femoris tendon, medial meniscal tear requiring partial meniscectomy and lateral meniscus tear not requiring meniscectomy. He has ongoing pain in the right knee and symptoms of femoral nerve dysaethetic pain/neuralgia and sensory alteration".

1. At Part 10a. under "My opinion and assessment of whole person impairment" the Medical Assessor wrote:

There is mild crepitation in the right knee attracting 5% LEI using Table 17 31, Page 544

There is 3 cm wasting of the right knee thigh musculature attracting 12% LEI referencing

Table 17.6 and is modified under Paragraph 3.14 of WCC Guides, 4th Edition (Reissued 1 March 2021).

AMA 5, Page 537, Table 17 10: Table for Knee Motion Impairment, is modified by the WCC Guides 4th Edition, Page 15, Paragraphs 3.16 and 3.17, as copied below.

Motion Mild 4% (10%) Moderate 8% (20%) Severe 14% (35%)

Flexion Less than 110° Less than 80° Less than 60° + 1%(2%) per 10° less than 60°

Varus 2° Valgus to 0°(neutral) 1° to 7° Varus 8° to 12° Varus, add 1° (2°) per 2° over 12°

Valgus 10° to 12° 13° to 15° 16° to 20°, add 1° (2°) per 2 over 20°

The added ROM L.I for the right knee ROM Impairment is 30% LEI.

Table 17-37 on Page 552 of AMA 5 is used to assess complete motor or sensory peripheral nerve loss in the lower limb which is not appropriate in this case. Partial sensory deficits are rated using the upper extremity Table 16 10 and then referring back to Table 17-37 as the measure of maximal impairment from which partial impairment can be calculated. There is Grade 2, equivalent to 80% sensory deficit and using Table 17 37 for dysaethesia there is 80% of 7% equalling 6% LEI and 80% of 2% LEI for sensory deficit equalling 2% LEI (after rounding), for a Total of 8% LEI. Diagnosis Based Impairment (DBE)

Referencing Table 17-33, Page 546, A.M.A 5, Partial Meniscectomy attracts 2% LEI.

Referencing Table 17-2 for permissible combinations, the greatest allowable impairment rating is obtained by range of movement method, 30% LEI combined with peripheral nerve 8% LEI to yield 36% LEI and under Table 17-3, equivalent to 14% WPI."

1. At Part 10.c of the MAC, the Medical Assessor commented on the other medical opinions and findings:

"Dr Ghabrial, orthopaedic surgeon medicolegal report 29 April 2024: assessed right knee 18% WPI, based on femoral nerve motor component 15% WPI and sensory component 3% WPI. No deductible proportion.

There is methodological error in that Table 17- 37 is only for complete motor or sensory loss of peripheral nerve and this is clearly not the case. The IME does not offer any other mode of assessment of impairment.

Dr Bentivoglio, orthopaedic surgeon medicolegal report 16 October 2024 assessed 7% WPI based on 5% LEI for post-traumatic chondromalacia patella, 2% LEI for partial meniscectomy and femoral nerve, equivalent to 10% LEI. No deductible proportion. Regarding the femoral nerve it appears both IMEs adopted the view that nerve conduction studies reported a significant femoral nerve lesion:

IME Dr Bentivoglio writes," damage to his femoral nerve is demonstrated apparently on 2 separate nerve conduction studies. He would have a maximum of 39% lower extremity impairment from Table 17-37. The IME writes," presumed abnormality seen on nerve conduction studies". The IME writes, "there is possibly some sensory abnormality involving his femoral nerve."

IME Dr Ghabrial writes "Nerve conduction studies suggested an injury to the right femoral nerve" and "the whole person impairment of the right femoral nerve and sensory injuries which were confirmed with nerve conduction studies and showed no improvement months later.

I would point out that the nerve conduction studies were reported as essentially neurologically normal with the results consistent with disuse atrophy (muscle wasting due to disuse as opposed to a femoral nerve lesion). The repeated nerve conduction studies were reported as showing no change. This has been clearly stated by the neurologist/neurophysiologist who performed the test and reported on the findings including the finding of a reduced femoral nerve compound muscle action potential as consistent with disuse atrophy as further detailed under Section 6 of the certificate. Disuse atrophy is properly assessed under muscle atrophy impairment. Symptoms of a femoral neuralgia/dysaethesia and subjective sensory changes can exist without confirmatory changes on nerve conduction studies and should be assessed under the appropriate tables as outlined in this certificate."

1. The appellant in his statement dated 4 February 2025 wrote:

"Furthermore, due to my pre-existing heart condition, I am restricted with the type of medications that I can use. Therefore, I regularly take Osteo Panadol (6 times per day), and Palexia (Tapentadol) when needed at night. Even though these provide some relief, the pain is quite persistent."

1. In his more recent statement dated 26 May 2025, the appellant made no reference to the medications that he was taking or to any change in medication.
2. Professor Ghabriel in his report of 29 April 2024 made no reference to the medications taken by the appellant at the time of his examination.
3. Dr Bentivoglio, in his report of 16 October 2024, noted that the appellant took various medication including Panadol Osteo, Endone and Palaxia. No reference was made to any proposed change in medications or to Amitriptyline.
4. In the Functional Capacity Evaluation Report of 7 March 2025, Ms Taylia Reedy, occupational therapist, noted that the appellant's medications were:

1. In the SIRA Certificate of Capacity dated 10 April 2025, Dr Kline, general practitioner, noted that the appellant was taking Palaxia. She noted "Duloxetine prescribed by pain specialist - unable to tolerate". In the SIRA Certificates of Capacity dated 17 March 2025 and

17 February 2025, no reference was made to medications. 2. In the SIRA Certificate of Capacity dated 7 May 2025, Dr Jazz Wei Jian Bon, general practitioner, made no reference to medications or to any change of medication. 3. The appellant asserts that the history obtained by the Medical Assessor is inadequate to meaningfully understand the nature and extent of the appellant's sensory deficits, both with and without the use of Amitriptyline, for the purposes of classifying and grading the sensory deficit. 4. The Appeal Panel notes that the Guidelines and AMA 5 make no reference to any requirement or need to assess the nature and extent of the sensory deficits, both with and without the use of medication, for the purposes of classifying and grading the sensory deficit. The Appeal Panel considers that although Amitriptyline provides some mild relief it does not change the grading of the sensory deficit. 5. The appellant has not identified any requirement in the Guidelines or AMA 5 for the Medical Assessor to take into consideration the implications or efficacy of medication in order to arrive at a proper assessment in accordance with the Guidelines or AMA 5. Neither of the IMEs relied on upon the parties applied the correct criterion, and neither referenced the use of medications in explaining how they arrived at their varying assessments with respect to the sensory component of the assessment. 6. The Appeal Panel considers when reading the MAC as a whole, that the Medical Assessor provided sufficient reasons for grading the peripheral nerve impairment as Grade 2. In particular, the Appeal Panel notes that under "ADL" the Medical Assessor reported that the appellant has difficulty negotiating up and down stairs or getting on and off his tractor but manages to do domestic tasks by pacing and modifying. The Medical Assessor noted that the appellant sold his cattle but uses a ride on mower to mow the lawns. 7. Table 16-10 AMA 5 provides that the description sensory deficit or pain for a Grade 1 classification is as follows: "Deep cutaneous pain sensibility present, absent superficial pain and tactile sensibility (absent protective sensibility) with abnormal sensations or severe pain, that prevents most activity". The description for a Grade 2 classification is as follows: "Decreased superficial cutaneous pain and tactile sensibility (decreased protective sensibility) with abnormal sensations or moderate pain, that may prevent some activities." 8. The Appeal Panel considers that the appellant is only prevented from doing some activities and is certainly not prevented from doing most activity. A Grade 2 rating is appropriate taking into account the activities performed by the appellant and the findings on examination made by the Medical Assessor. 9. Further, the Appeal Panel notes that even if the appellant had been assessed as Grade 0 (100%) under Tables 16-10 and 17-37 of AMA 5, impairment for the femoral nerve sensory deficit would be 2% LEI combined with 7% LEI for dysaesthesia totalling 9% LEI. Then 30% LEI (for restricted range of movement) combined with 9% LEI for sensory loss/dysaesthesia totals 36% LEI which converts to 14% WPI per AMA 5 p 527 T 17.3. It follows that assessment of the sensory deficit as grade 0, 1 or 2 under Table 16-10 would not alter the WPI percentage. (Cl 3.32 of the Guidelines provides: "When assessing the impairment due to peripheral nerve injury (AMA 5 pp 550-52) assessors should read the text in this section. Note that separate impairments for the motor, sensory and dysaesthetic components of nerve dysfunction in AMA 5 Table 17-37 (p 552) are to be combined").

Ground 2 - failing to make an adjustment for the effects of treatment

1. The appellant submits the Medical Assessor failed to make an adjustment for the effects of treatment, as permitted by cl 1.32 of the Guidelines.
2. Clause 1.32 of the Guidelines provides that:

"Where the effective long-term treatment of an illness or injury results in apparent substantial or total elimination of the claimant's permanent impairment, but the claimant is likely to revert to the original degree of impairment if treatment is withdrawn, the assessor may increase the percentage of WPI by 1%, 2% or 3%. This percentage should be combined with any other impairment percentage, using the Combined Values Chart. This paragraph does not apply to the use of analgesics or anti-inflammatory medication for pain relief."

1. The first reference to the appellant taking Amitriptyline is in the MAC. The Medical Assessor examined the appellant on 25 August 2025. Clearly Amitriptyline has not been a long-term treatment.
2. Clause 1.32 provides that the treatment must result in apparent substantial or total elimination of appellant's permanent impairment. Amitriptyline has not resulted in apparent substantial or total elimination of appellant's permanent impairment.
3. The Appeal Panel notes that no other doctor made adjustment for effects of treatment.
4. The Appeal Panel was not satisfied that the treatment including medication taken by the appellant was long-term treatment or treatment that resulted in an apparent substantial or total elimination of his permanent impairment, as required by cl 1.32 of the Guidelines. The Appeal Panel finds no error nor the application of incorrect criteria by Medical Assessor in not making an adjustment for the effects if treatment.
5. For these reasons, the Appeal Panel has determined that the MAC issued on