Coles Supermarkets Australia Pty Ltd v Byrne

DETERMINATION OF APPEAL PANEL
CITATION:	Coles Supermarkets Australia Pty Ltd v Byrne [2023] NSWPICMP 639
APPELLANT:	Coles Supermarkets Australia Pty Ltd
RESPONDENT:	Leanne Byrne
APPEAL PANEL
MEMBER:	Jane Peacock
MEDICAL ASSESSOR:	John Brian Stephenson
MEDICAL ASSESSOR:	Gregory McGroder
DATE OF DECISION:	5 December 2023
CATCHWORDS:	WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; appellant alleged error in the failure of the Medical Assessor (MA) to make a deduction under section 323 for the contribution of a pre-existing condition to the overall level of permanent impairment assessed and failed to give adequate reasons; a deduction can only be made if the prior condition of the knee has contributed to the overall level of permanent impairment assessed; here the level of permanent impairment assessed is based on the fact that there has been a knee replacement; the fact that the worker was asymptomatic is a factor to be taken into account but is not determinative; the respondent progressed within little time (6 years) after injury to a total knee replacement; on the available evidence the knee replacement was performed because of both the injury and the long standing changes to the knee; the prior condition of the knee should have been taken into account by the MA and as the contribution of the prior condition would be too difficult or costly to determine, a deduction of one-tenth which is not at odds with the available evidence, should have been made. Medical Appeal Panel satisfied as to error; Held – Medical Assessment Certificate revoked.

BACKGROUND TO THE APPLICATION TO APPEAL

On 31 July 2023 the employer Coles Supermarkets Australia Pty Ltd (the appellant) lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr SK Cyril Wong, a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on 3 July 2023.
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.
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.
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.
The assessment of permanent impairment is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4^th ed
1 March 2021 (the Guidelines) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5^th ed (AMA 5).

PRELIMINARY REVIEW

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.
The appellant sought that the worker be re-examined by a Medical Assessor member of the Appeal Panel. As a result of the Appeal Panel’s preliminary review, the Appeal Panel determined that it was not necessary for the worker to undergo a further medical examination because although the Appeal Panel found error, there was sufficient material before the Appeal panel to enable a determination to be made.

EVIDENCE

Documentary evidence

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.

Medical Assessment Certificate

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.

SUBMISSIONS

Both parties made written submissions. They are not repeated in full, but have been considered by the Appeal Panel.

FINDINGS AND REASONS

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.
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.
The matter was referred to the Medical Assessor by the Commission as follows:
“The following matters have been referred for assessment (s 319 of the 1998 Act):
·    Date of injury:   28 October 2014
·    Body parts/systems referred:        Left lower extremity (knee)
·    Method of assessment:                  Whole Person Impairment”
The Medical Assessor issued a MAC as follows:

Body Part or system

Date of Injury

Chapter,

page and paragraph number in NSW workers compensation guidelines

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

% WPI

WPI deductions pursuant to S323 for pre-existing injury, condition or abnormality (expressed as a fraction)

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

1. Left lower extremity (knee)

28 October 2014

Chapter 3

P13-23

Chapter 17

P523 - 564

20%

Nil

20%

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

20% WPI

The employer appealed. The complaint concerned both the assessment of the overall impairment of the left knee and the failure to make a deduction under s 323.
In summary, the worker Ms Leanne Byrne (the respondent) submitted on appeal that the Medical Assessor did not make a demonstrable error or make an assessment on the basis of incorrect criteria and the MAC should be confirmed.
The Medical Assessor took a history as follows:
“Brief history of the incident/onset of symptoms and of subsequent related events, including treatment: On 28 October 2014, Ms Byrne twisted her left knee at work while attempting to move a heavy cage to retrieve a box behind the cage. The pain persisted and Ms Byrne consulted her general practitioner at Erskin Park about a week later. After an MRI of the knee Ms Byrne was referred to orthopaedic surgeon Professor Al Muderis who diagnosed a medial meniscus tear at the left knee. Professor Muderis then performed an arthroscopic repair to the tear of the meniscus on 16 February 2015. The condition of the left knee had deteriorated with time. On 5 February 2018,
Ms Byrne felt a snap in her left knee which soon became swollen. She consulted Professor Muderis again on 20 March 2018 and the doctor recommended total knee replacement. The surgery was performed on 3 February 2020. Ms Byrne begun to experience pain in her right knee about a month after DOI and the right knee pain got worse with time due to overcompensating for her left knee. The right knee was treated with physiotherapy and no surgery was performed.
Present treatment: Ms Byrne is at present having no specific treatment for her left knee. She has no treatment for the right knee after the left knee replacement. Ms Byrne now takes for Celebrex daily and Dolacet when necessary twice a week.
Present symptoms: Ms Byrne complains of constant mild pain at the left knee and the pain gets worse on too much working and carrying heavy crates at work. The left knee gets swollen. The knee does not give way. The right knee has no symptoms now.
Details of any previous or subsequent accidents, injuries or condition: There was no other prior injury and no subsequent injury.
General health: Ms Byrne rates her general health as good with no chronic illness or routine medication.
Work history including previous work history if relevant: Ms Byrne attended school year 10. She joined the work force at age 14 working in a factory doing sewing. She then started to work for Coles and she is still there working full time.
Social activities/ADL: Ms Byrne lives with her husband, her dad and her daughter. Ms Byrne can drive normally. She can walk normally.”
The Medical Assessor reviewed the special investigations as follows:
“02/07/2015 X-rays knees - There is mild degenerative narrowing of the medial tibiofemoral and medial patellofemoral compartments, associated with small peripheral osteophytes. The lateral tibiofemoral joint spaces are well preserved.
21/09/ 2015 MRI left knee - Severe medial compartmental OA with a chronically torn and desiccated body and posterior horn/posterior root of the medial meniscus with resultant medial extrusion of the medial meniscus; small joint effusion and Baker's cyst.
20/06/2017 MRI left knee - Previous partial medial meniscectomy without definite retear; severe medial femorotibial arthritis with mild lateral compartment arthritis. Chronic sprain of ACL and MCL
02/02/2021 X-rays left knee – TKR noted in a satisfactory position with no apparent complication.”
The Medical Assessor conducted a physical examination which he recorded as follows:
“Leanne Byrne appeared well in no apparent physical distress. She was walking normally. She sat comfortably throughout the interview. She was informed at the time of examination not to engage in any manoeuvre beyond what she could tolerate or which might cause harm or injury. Her height was 155cm and she weighed 54kg.
Left total knee replacement

AMA5 T17-35 as modified in section SIRA4 section p21

Left knee

a. Pain

Moderate Continual

10

b. Range of Motion

25

c. Stability (max movement)

A-P <5mm 10 points;

10

M-L <5^o 15 points

15

Total point score before deduction

60

Deduction d, e, f

d. Flexion contracture - Nil

0

e. Extension Lag - Nil

0

Alignment-Valgus -3 degrees

0-4^o 3 points per degree

6

Sum deduction

6

Final point score after deduction

54 Points

AMA5 T17-35

50-84 points - Fair results

20 % WPI

Right knee
The right knee was at valgus 10^o with no swelling or tenderness. The right knee had flexion at 130 degrees with no flexion contracture. The right knee was stable with no other rateable signs.”

The Medical Assessor summarised his diagnosis and findings as follows:
“summary of injuries and diagnoses:
Leanne Byrne is a 55-year-old woman who had an accident at work sustaining a soft tissue injury to her left knee. Ms Byrne had an arthroscopic repair to the tear of the meniscus and later a total knee replacement. She also experienced pain at the right knee afterwards.
· consistency of presentation
There is no inconsistency found in this examination.”
The Medical Assessor explained his impairment assessment as follows:
“Ms Byrne had injury to the left knee while at work. I have assessed the whole person impairment at 20%.
In making that assessment I have taken account of the following matters: -
The left knee was evaluated according to AMA5 T17-35 as modified in section SIRA4 section p21. The final point score after deduction was 54 points indicating a fair result at 20% WPI.”
The Medical Assessor did not identify any prior condition.
The Medical Assessor made brief comment on the other evidence and medical opinion which was before him as follows:
“13 December 2021 Dr Peter Giblin in his IME report stated that Ms Byrne has moderate occasional pain in her left knee and this will wake her up at night. He rated the left total knee replacement had a total of 40 points, a poor result attracting 30% WPI.
9 June 2022 Dr Paul Miniter in his IME report stated that the left total knee replacement had a good outcome (94 points according to AMA5 Table 17-35). However, the doctor did not think the injury was work related and gave 100% deduction.
I have found the left knee to have a fair result from a total knee replacement; there was no apportionment required.”
The Medical Assessor has made an assessment based on the knee replacement finding a fair result.
The appellant submitted that this assessment was on the basis of incorrect criteria.
The appellant made a comparison between the pain levels reported by the worker at the assessment by the Medical Assessor, the assessment by Dr Giblin, (the IME qualified on behalf of the worker) and the assessment by Dr Miniter (the IME qualified on behalf of the appellant).
Because of what the appellant refers to as a discrepancy in pain levels reported to each
doctor and the appellant submits that preference should be given to that recorded by
Dr Miniter.
The appellant says that in addition there is also inconsistency in respect of the alignment valgus which was scored 0 by the IMEs but the Medical Assessor made a deduction of 6 points for the valgus found by him.
The appellant submitted:
“…the rating for the respondent’s pain level should be modified to reflect the findings of Dr Miniter on the basis there is no contemporaneous evidence of ongoing pain or the need for any analgesics. Furthermore the last certificate of capacity on file dated 23/07/2020 states the respondent was fit for pre-injury duties. She has been working in this role since.
The appellant submits the score for the alignment valgus should also be modified pursuant to paragraph 1.36 of the Guidelines to reflect the remaining tow assessments Dr Minter and Dr Giblin being 0.”
Paragraph 1.36 of the Guidelines provides which deals with inconsistent presentation as follows:
“AMA5 (p 19) states: ‘Consistency tests are designed to ensure reproducibility and greater accuracy. These measurements, such as one that checks the individual’s range of motion are good but imperfect indicators of people’s efforts. The assessor must use their entire range of clinical skill and judgment when assessing whether or not the measurements or test results are plausible and consistent with the impairment being evaluated. If, in spite of an observation or test result, the medical evidence appears insufficient to verify that an impairment of a certain magnitude exists, the assessor may modify the impairment rating accordingly and then describe and explain the reason for the modification in writing.’ This paragraph applies to inconsistent presentation only.”
The appellant’s submissions are misconceived.
The Medical Assessor did not find that the worker was inconsistent in her presentation rather he found she was consistent in her presentation. Paragraph 1.36 does not apply here.
The Medical Assessor was entitled to rely on his clinical findings on the day of examination and his examination was through and consistent. The pain levels reported to him are consistent with clinical findings. The assessment of a fair result was in accordance with correct criteria. The deduction made by the Medical Assessor for valgus alignment makes no difference to the calculation of fair result. There is no error.
The appellant also complains about the failure to make a deduction under s 323.
A deduction under s 323 can only be made if the pre-existing condition, abnormality or injury has contributed to the level of permanent impairment assessed. Where the extent of the deduction would be too difficult or too costly to assess the deduction should be one-tenth unless that is at odds with the available evidence.
The Medical Assessor has made no deduction.
The appellant points to the MRI scan taken three weeks after injury which shows the presence of degenerative changes. The treating surgeon A/Prof Munjed Muderis noted the MRI scan findings and that “the cartilage damage on the medial compartment as well as the patellofemoral compartment looks to be longstanding”. A/Prof Meuderis also noted:
“in relation to her cartilage damage in the medial joint line this will progress to arthritis and she may require total knee replacement in the future”.
The respondent worker points out that there is no evidence she was symptomatic prior to injury.
A deduction can only be made if the prior condition of the knee has contributed to the overall level of permanent impairment assessed. Here the level of permanent impairment assessed is based on the fact that there has been a knee replacement. The fact that the worker was asymptomatic is a factor to be taken into account but is not determinative. The respondent progressed within little time (6 years) after injury to a total knee replacement. On the available evidence the knee replacement was performed because of both the injury and the long standing changes to the knee. The prior condition of the knee should have been taken into account by the Medical Assessor and as the contribution of the prior condition would be too difficult or costly to determine, a deduction of one-tenth which is not at odds with the available evidence, should have been made. After deduction the assessment is 18% WPI.
The appeal Panel will revoke the MAC on this basis and issue a new MAC.
For these reasons, the Appeal Panel has determined that the MAC issued on
3 July 2023 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

APPEAL PANEL

MEDICAL ASSESSMENT CERTIFICATE

Injuries received after 1 January 2002

Matter number:	W1808/23
Applicant:	Leanne Byrne
Respondent:	Coles Supermarkets Australia Pty ltd

This Certificate is issued pursuant to s 328(5) of the Workplace Injury Management and Workers Compensation Act1998.

The Appeal Panel revokes the Medical Assessment Certificate of Medical Assessor SK Cyril Wong and issues this new Medical Assessment Certificate as to the matters set out in the table below:

Table - whole person impairment (WPI)