Insurance Australia Limited t/as NRMA Insurance v Rillstone

DETERMINATION OF REVIEW PANEL
CITATION:	Insurance Australia Limited t/as NRMA Insurance v Rillstone [2024] NSWPICMP 566
CLAIMANT:	Elliott Rillstone
INSURER:	NRMA
REVIEW PANEL
MEMBER:	Stephen Boyd-Boland
MEDICAL ASSESSOR:	Shane Moloney
MEDICAL ASSESSOR:	Drew Dixon
DATE OF DECISION:	14 August 2024
CATCHWORDS:	MOTOR ACCIDENTS – Motor Accident Injuries Act 2017; degree of permanent impairment; physical injury; combined certificate; Medical Assessor Curtin assessed left knee significant post-surgical scarring, finding a 2% whole person impairment (WPI); Medical Assessor Nair assessed left knee, left knee multiligamentous injury finding an 11% WPI and also finding a 2% WPI for scarring; Medical Assessor Curtin then issued a combined certificate certifying that the claimant’s total WPI arising from the accident was 15%; Held – Medical Review Panel (Panel) found the left knee injury being meniscal tears, patella-femoral arthritis and flexion contracture resulted in a WPI of 6%; Panel confirmed a finding of 2% WPI for scarring; Panel revoked the earlier certificate, reissued the certificate and issued a new combined certificate.
DETERMINATIONS MADE:	CERTIFICATE OF DETERMINATION 1. The following injuries caused by the motor accident give rise to a permanent impairment of 8% and is not greater than 10%: 1. left leg medial and lateral meniscal tears, patella-femoral arthritis and left knee scarring 8%.

STATEMENT OF REASONS

INTRODUCTION

On 30 October 2018, Elliott Rillstone (the claimant) sustained injury in a motor vehicle accident (the accident).
Mr Rillstone was riding his pushbike on a bike path when a car came out of a driveway and failed to give way to him. He was knocked off his pushbike and sustained a dislocation of the left knee. The ambulance attended the scene of the accident and transported him to the Northern Beaches Hospital.
Insurance Australia Ltd t/as NRMA Insurance (the insurer) is the relevant insurer.
In this context claims and entitlements to benefits and compensation are governed by the provisions of the Motor Accident Injuries Act 2017 (the MAI Act).
Claims are initiated by lodgement of an Application for Personal Injury Benefits and also an application for Damages under Common Law arising out of the motor accident against (the insurer). The legislation provides a scheme of statutory benefits (under Part 3) and lump sum damages (under Part 4).
Statutory benefits include weekly benefits for lost earnings and treatment and care needs for accident-related injuries.
Claims for damages include damages for economic losses and possibly non-economic loss resulting from accident-related injuries.
Damages for non-economic loss are regulated by the provisions in Part 4, Division 4.3 of the MAI Act. Entitlement to those damages is restricted by s 4.11 to persons who have a greater than 10% whole person impairment (WPI) as a result of the injuries sustained in the accident.
If there is a dispute about the degree of the claimant’s permanent impairment, damages for non-economic loss cannot be awarded and the dispute must be referred to a Medical Assessor for determination.
Permanent impairment is to be assessed in accordance with Chapter 6 of the Motor Accident Guidelines (the Guidelines) which are largely based on the American Medical Association’s Guides to the Evaluation of Permanent Impairment, Fourth Edition (AMA 4 Guides).
Pursuant to Schedule 2, cl 2 of the MAI Act, various matters are declared to be medical assessment matters, including “(a) the degree of permanent impairment of the injured person that has resulted from the injury caused by the motor accident (including whether the degree of permanent impairment is greater than a particular percentage).”
Chapter 7, division 7.5 of the MAI Act provides for medical assessments by the Personal Injury Commission (Commission) including provisions relevant to an original medical assessment, further medical assessments and the review of medical assessments by this Review Panel.
Various medical disputes have arisen, and medical assessment matters were referred to the Commission for assessment.
This dispute is in relation to whether the degree of permanent impairment sustained by the claimant as a result of the injury caused by the accident is greater than 10%. This constitutes a medical dispute within the meaning of the MAI Act.

The Medical Assessments

Medical Assessor Geoffrey (Paul) Curtin

The following injuries were referred by the Commission to Medical Assessor Geoffrey (Paul) Curtin for assessment:
(a) left knee significant post-surgical scarring.
The results of the medical assessment were set out in the certificate dated 24 March 2023.
Medical Assessor Geoffrey (Paul) Curtin found that the following injuries were caused by the motor accident:
(a) left knee significant post-surgical scarring.
The Medical Assessor Geoffrey (Paul) Curtin determined the degree of permanent impairment as follows:

Body part or System

Guidelines

AMA Guidelines

Permanent

Yes/No

Current %WPI

%WPI from pre-existing or subsequent causes

%WPI due to motor accident

Left Knee

TEMSKI

Yes

2%

0%

2%

Medical Assessor Anil Nair

The following injuries were referred by the Commission to Medical Assessor Anil Nair for assessment:
(a) left knee.
The results of the medical assessment were set out in the certificate dated 26 May 2023.
Medical Assessor Anil Nair found that the following injuries were caused by the motor accident:
(a) left knee multiligamentous injury.
The Medical Assessor Anil Nair determined the degree of permanent impairment as follows:

Body part or System

Guidelines

AMA Guidelines

Permanent

Yes/No

Current %WPI

%WPI from pre-existing or subsequent causes

%WPI due to motor accident

Left Knee

Table 64 Page 85

Yes

10%

0%

10%

Left Knee

Table 64 Page 85

Yes

1%

0%

1%

Left Knee

TEMSKI

Yes

2%

0%

2%

Medical Assessor Geoffrey (Paul) Curtin Combined Certificate

The claimant was assessed by Medical Assessor Geoffrey (Paul) Curtin who issued an assessment outcome (medical assessment) in a certificate dated 24 March 2023. The injury that was referred to Medical Assessor Geoffrey (Paul) Curtin was left knee significant post-surgical scarring. Medical Assessor Geoffrey (Paul) Curtin determined that the WPI arising from the left knee significant post-surgical scarring was 2%.
The claimant was assessed by Medical Assessor Anil Nair who issued an assessment outcome (medical assessment) in a certificate dated 26 May 2023. The injury that was referred to Medical Assessor Anil Nair was left knee. Medical Assessor Anil Nair determined that the WPI arising from the left knee injury was 10% and 1%, being 11%. Medical Assessor Anil Nair then added scarring at 2%. Medical Assessor Anil Nair determined that the WPI was 13%.
Medical Assessor Geoffrey (Paul) Curtin issued a combined certificate dated 29 May 2023, certifying that the claimant’s total WPI arising from the accident is 15%. That combined certificate included the WPI of 13% determined by Medical Assessor Anil Nair and the WPI of 2% determined by Medical Assessor Geoffrey (Paul) Curtin.
Pursuant to s 7.26 (4) of the MAI Act if a medical assessment under this division is based on the assessments of two or more single Medical Assessors (resulting in a combined certificate as to the total degree of permanent impairment) (a "combined certificate assessment"), the combined certificate assessment cannot be the subject of review under this section except by way of the review of any of the assessments of the single medical assessor on which the combined certificate assessment is based.

The review

The insurer lodged an application for review of the assessment of Medical Assessor Anil Nair set out in the certificate dated 26 May 2023.
On 27 July 2023 the delegate of the President determined there was reasonable cause to suspect a material error in that assessment. It was accepted that the Medical Assessor has failed to disclose his path of reasoning for assessing the left knee injury as 10% and 1%.
The President of the Commission then convened a panel to conduct the review.
The injuries that were referred to Medical Assessor Anil Nair were left knee injury.
Clause 14F of Schedule 1 of the Personal Injury Commission Act 2020 (the PIC Act) provides that the new review provisions apply in relation to a decision of a decision maker. A ‘new decisionmaker’ is defined in cl 14A(1) of Schedule 1 of the PIC Act. As the medical assessment, the subject of the review, was made on or after 1 March 2021, the new provisions apply.
The new review provisions provide at s 7.26(5) of the MAI Act that a review panel consists of two Medical Assessors and a Member assigned to the Motor Accidents Division of the Commission.
Part 5 of the PIC Act enables the Commission to make rules with respect to practice and procedure for the Commission including proceedings before a panel reviewing a decision of a Medical Assessor – see s 41(2) of the PIC Act.
Rules 127 to 130 of the Personal Injury Commission Rules 2021 (PIC Rules) are made pursuant to Part 5 of the PIC Act. A review panel determines how it conducts the proceedings and may determine the proceeding solely based on the written application.
The Review Panel was comprised of two specialist medical practitioners and a legal member. The Review Panel met on a number of occasions and provided Directions to the parties.
The review is a process involving the Review Panel seeking evidence, including additional material provided by the parties and further submissions, and potentially further medical examination, then meeting on a number of occasions to discuss the evidence before the Review Panel and to reach a view on the relevant issues and reduce that to written reasons.
The Review Panel is not required to choose between competing medical opinions and is required to form its own opinion: Insurance Australia Group Ltd v Keen [2021] NSWCA 287 at [40], [41] and [45] and Insurance Australia Ltd v Marsh [2022] NSWCA 31 at [11], [21] and [64].
Both the claimant and the insurer are legally represented and have the opportunity to provide submissions and to identify and narrow the issues in dispute so as to meet the objectives of the MIA Act.
Whilst the review is by way of a new assessment of all matters with which the medical assessment is concerned this occurs in the context of the initial assessment and certificate, the application for review of the assessment and the determination to conduct a review.
We note that the injury that was referred to Medical Assessor Geoffrey (Paul) Curtin was left knee significant post-surgical scarring. That assessment is not the subject of this review.

Material before the Review Panel

The Review Panel issued directions to the parties required each party to file an indexed, paginated bundle of documents they relied for the review.
The claimant lodged:
The insurer lodged a bundle of documents described as “2023.09.29 Insurer's Final Index of Documents - Review Application” being 171 pages.
The insurer relied upon submissions dated 25 January 2022 and 23 June 2023.
The claimant relied upon submissions dated 3 July 2023.
Pursuant to s 7.26(6A) of the MAI Act the Review Panel agreed that Medical Assessor Shane Moloney would conduct the medical re-examination of the claimant for the purposes of the review.
Re-examination of Elliott Rillstone on 10 November 2023 by Medical Assessor Shane Moloney was arranged.
In Rahman v Insurance Australia Ltd t/as NRMA Insurance [2022] NSWSC 1079 Justice Basten referred to Court of Appeal comments on the volume of material which is routinely provided to Medical Assessors. Justice Basten confirmed that in reasons accompanying a certificate there was not a need to refer to all the documentation to which he or she has had access, but rather to be discriminating as to that material.

The insurer’s submissions

The insurer, in its submission of 28 January 2023, refers to the Guidelines and AMA 4 Guides. The submissions specifically consider, Unilateral muscle atrophy, right knee range of motion, arthritis, ligament laxity, medial meniscus debridement and scarring.
The insurer, in its submission of 23 June 2023, refers to both the certificate of Medical Assessor Nair and combined certificate of Medical Assessor Curtin.
The submission make reference to obvious errors in the combined certificate of Medical Assessor Curtin. There was reference to an obvious error in the determination of WPI. The insurer did not include reference to any of the legislative provisions in relation combined certificates or authorities relating to obvious error.
The insurer in its submission of 23 June 2023 identified three specific issues in relation to Medical Assessor Nair’s assessment.
That Medical Assessor Nair:
(a)    failed to set out his path of reasoning as required in Wingfoot Australia Partners Pty Limited v Kocak[2013] HCA 43;
(b)    failed to properly assess the claimant with regards to the AMA 4 Guidelines, and
(c)    failed to engage with, review and consider the material provided.
The insurer in its submission of 23 June 2023 subsequently identified four specific issues in relation to Medical Assessor Nair’s assessment.
That Medical Assessor Nair:
(a) failed to provide a specific diagnosis for the claimant’s left knee injury, and failed to disclose his path of reasoning when assessing 10% and then a separate 1% impairment in the left knee according to the diagnosis-based estimate method (despite not providing a proper diagnosis), contrary to the requirements in s 7.23 of the MAI Act and the common law Wingfoot;
(b)    failed to set out his path of reasoning when assessing 2% impairment for scarring;
(c)    failed to review and consider the material provided to him, or if he did consider it, failed to comment on any or all of the material, and therefore has erred the exercise of the diagnosis-based estimate method in circumstances where he ignored the contemporaneous evidence, and
(d)    failed to properly assess the claimant with regards to the AMA 4 Guides, as there is no evidence to suggest he conducted tests for ligament laxity, muscle atrophy, gait derangement or manual muscle testing (see Parts 3.2b to 3.2d of the AMA 4 Guides).

The claimant’s submissions

The claimant did not accept that the Medical Assessor has failed to disclose his path of reasoning for assessing the left knee injury as 10% and 1%.
The claimant noted that in relation to the 2% assessment for scarring that this was also the conclusion reached by Medical Assessor Geoffrey (Paul) Curtin. The injury that was referred to Medical Assessor Geoffrey (Paul) Curtin was left knee significant post-surgical scarring.

Medical evidence

Dr Chia in his examination report dated 22 November 2018, reported that the medial meniscus was reduced, and the anterior horn debrided as well as a peripheral tear lateral posterior horn repaired with sutures and debrided.
In his report dated 25 September 2020 Dr Bodel concluded “He had suffered serious injury to the left knee including multiple ligamentous injuries involving the cruciate ligaments and the medical ligament as well as a posterior horn tear of the medial meniscus”.
Dr Bodel concluded “He has had a complex ligamentous injury and meniscal injury to the region of the left knee. There is soft tissue injury but no definite fracture.”
In his report dated 25 September 2020 Dr Bodel concluded “There is a direct causal link between this episode of injury while riding his pushbike and the ongoing problems with the left knee.”
Dr Bodel noted that examination revealed a mild left-sided limp. There was no leg length inequality or spinal deformity. He has a good range of back movement and no impairment of straight-leg-raising. The left quadriceps muscles is 1.4cm smaller than the right when measured 10cm above the superior pole of the left patella. On testing range of movement flexion of the right knee was 130° with 0° extension. Left knee was 120° flexion and extension -5°.
Dr Bodel noted “ …the scarring is very significant, associated with the multiple surgical procedures and I would rate this as moderate complex surgical scarring and a 2% Whole Person Impairment under the TEMSKI scale.”
Dr Bodel concluded:
“I have assessed Mr Rillstone in accordance with the Motor Accident Authority Guidelines. He has moderate persisting medial and anterior cruciate ligament laxity and in accordance with Table 64, on - Page 85, this constitutes a 10% Whole Person Impairment. There has also been a partial meniscectomy in the medial meniscus which attracts another 1% Whole Person Impairment from that same table. The restricted range of movement cannot be combined with those ratings and therefore the injury to the left knee is an 11% Whole Person Impairment on the basis of the Diagnosis Based Estimates. As I indicated in the History section, the scarring is quite significant and I would rate that as a 2% Whole Person Impairment under the TEMSKI scale, giving a 13 % Whole Person Impairment overall. There is no other rateable impairment and no deduction for pre-existing impairment.”
Dr Porteous provided a report dated 13 October 2021. Dr Porteous described the accident and concluded it resulted in “putting his left knee out which then collapsed with substantial pain”.
Dr Porteous concluded the diagnosis of “… substantial left knee soft tissue and bony contusion and injuries including a rupture of ACL graft repair, medial collateral ligament rupture and injury to both the lateral and medial meniscus requiring three operations.”
Dr Porteous noted that examination disclosed 0° to 133° flexion on the right and 0° to 130° on the left. There was no patellofemoral pain. There was evidence of clear anterior cruciate laxity on directed observed testing, which would be considered of a moderate degree (Table 64, 7% WPI). There was no patellofemoral compression pain. There was clearly on observation, a decrease in the left thigh width 10cm above the patella. He was walking with a normal gait with no evidence of limping.
Dr Smith provided the insurer with a report dated 16 November 2021.
Dr Smith noted “He injured his left knee …” and that the accident resulted in the claimant:
“… sustaining soft tissue and ligamentous injuries to his left knee. He has bilateral knee osteoarthritis, based on today’s clinical examination. It would appear to me that the left knee osteoarthritis that was present prior to the accident has been probably made somewhat worse by the accident.”
Dr Smith noted that examination revealed the right knee to have a slight varus deformity and has 5° of hyperextension and flexes to 125°. The right knee is stable. McMurray’s test is normal. The scarring on the right knee is consequent to hamstring harvesting. On the left, there is no deformity of the left knee which has no hyperextension and flexes to 110°. There is crepitus throughout the range. He has a positive Osmond-Clark test. The left knee is stable. The left thigh is a centimetre narrower than the right thigh.
Dr Smith noted “I would concur that there is scarring in both knees, which would amount to an assessable impairment. I would have thought that a 2% whole person impairment would be the maximum one could describe to the scarring of both his knees.”
In response to the assessment of Dr Bodel, Dr Smith noted “Any impairment assessment should be based on the radiology, and he should have the x-rays mentioned in the paragraphs above. Using the range of motion method available in AMA 4, there is no assessable impairment in either knee, as yet.”

Medical Assessor Nair noted:
“Pre accident history
Mr Rillstone stated that he did have a left knee ACL reconstruction about 10 years prior to the subject injury. He stated that following the reconstruction, he returned to full and unrestricted sport, including rugby. He did not have any clinically significant symptoms prior to such subject accident.
History of the motor accident
Mr Rillstone stated that he was riding a push bike on Pittwater Road on the 30 October 2018. He was hit on the right-hand side by a motor vehicle. The driver stopped. He was taken to the Northern Beaches Hospital. An emergency assessment was performed including an angiogram to rule out a catastrophic vascular injury. He was admitted under Orthopaedic Surgeon, Dr. Sam Chia. He stated he underwent three surgeries under Dr Chia, the first was on the 2 November 2018 in the form of an open MCL repair. The second was on the 22 November 2018 in the form of an arthroscopy as well as bone grafting. The third was on the 23 May 2019 in the form of an arthroscopic ACL reconstruction with a contralateral hamstring graft.
Current symptoms
He has left knee pain at rest. The pain is 2/10 to 3/10 in magnitude. There is further increase in symptoms with the heavier gradation of tasks including pushing a lawnmower and pushing uphills.”
Medical Assessor Nair reported flexion of 130 degrees in the right knee and120 degrees in the left knee, and extension of 0 degrees in the right knee and 5 degrees in the left knee.
Medical Assessor Nair found that the condition was permanent as it is unlikely to change by more than 3% in the next year.
Medical Assessor Nair then assessed a 10% permanent and then a separate 1% permanent impairment.
The claimant was assessed by Medical Assessor Anil Nair in relation to the left knee significant post-surgical scarring permanent impairment of 2%.
Medical Assessor Nair concluded the total permanent impairment was 13%.

Medical examination

Pursuant to s 7.26(6A) of the MAI Act the Review Panel agreed that Assessor Shane Moloney would conduct the medical re-examination of the claimant for the purposes of the review.
Elliott Rillstone attended the medical suite at the Commission rooms on 10 November 2023 was examined by Medical Assessor Shane Moloney.
The Examination Report of Assessor Shane Moloney is as follows.

Introduction

Mr Rillstone was working full-time as a logistics operator for Burton snowboard manufacturer as well as studying for a Masters of logistics at the time of the accident. He got married in April 2022 and has one child. He states that at the time of the accident he was very fit with cycling 200 to 250 km per week and surfing on a daily basis.
There was a past history of having a left knee Anterior Cruciate Ligament repair in 2008. He states that this left knee was totally asymptomatic at the time of the accident as he had been pain free undertaking snowboarding, playing rugby and touch football.

History of motor accident

Mr Rillstone was riding his pushbike on a bike path when a car came out of a driveway and failed to give way to him. He was knocked off his pushbike and sustained a dislocation of the left knee. The ambulance attended the scene of the accident and transported him to the Northern Beaches Hospital.

Subsequent history and treatment

On the day of the accident at the hospital, his left knee was relocated and investigated with a CT and MRI scan. He was under the care of an orthopaedic surgeon Dr Chia. There were three surgical procedures undertaken to the left knee. The first on 2 November 2018 when he had an open Medial Cruciate Ligament repair. The second operation six weeks later involved the meniscal repair and at the third operation on 23 May 2019 there was an ACL reconstruction using the right hamstring as a graft. He was off work initially for two months and then worked part-time for two to three months. Extensive physiotherapy was undertaken after each surgery.
There were no further injuries or conditions sustained since the motor accident.
Medical Assessor Shane Moloney found that the claimant had sustained a left knee medial and lateral meniscal tears, patella-femoral arthritis and left knee scarring.

Current symptoms

Mr Rillstone finds the left knee becomes painful with stiffness when in a fixed position such as when he is flying for work. The pain increases in cold weather. There has been a marked decrease in fitness since the accident with a weight gain of 20kg. He has returned to cycling but on a much limited range with some anxiety noted. He also has returned to snowboarding but is much more cautious in this pursuit. He walks on a regular basis as he has two Irish setter dogs. Driving is not a problem, but his left knee stiffens with prolonged sitting. No gardening is undertaken now as he lives in an apartment with his wife and child.

Current treatment

Mr Rillstone takes no analgesics at present and has no manual therapy.

Clinical examination

Mr Rillstone walked into the medical suite with a normal gait and sat comfortably during the interview. His height was measured at 195cm and weight 147kg.

Left knee

On testing range of movement flexion of the right knee was 130° with 0° extension. Left knee was 110° flexion and extension -5°. This is equivalent to a flexion contracture of 5°, which is a mild impairment of 4% WPI in Table 41.
There was slight muscle wasting of the left thigh. The circumference of the lower thighs was 55cm on the right and 54cm on the left (10cm above the superior patella pole) and at the maximum circumference of the calves 47cm bilaterally. No ligament laxity was noted of either knee but there was tenderness on palpation of the patellofemoral joint with crepitus on passive movement.
Using the footnote Table 62 of AMA 4 Guides, a history of direct trauma with patellofemoral pain and crepitation on physical examination is 2% WPI.
Dr Chia in his examination report dated 22 November 2018, reported that the medial meniscus was reduced, and the anterior horn debrided as well as a peripheral tear lateral posterior horn repaired with sutures and debrided. Using Table 64, this is equivalent to a partial meniscectomy of the medial and lateral meniscus which is 4% WPI.
However, using Table 6.5 of Motor Accident Assessment Guidelines, it is not permissible to combine range of motion or muscle atrophy with a DRE assessment (which was obtained using AMA 4 Guides Table 64 for the partial meniscectomies). Therefore, the final WPI is 4 % WPI for partial menisectomy lateral and medial (table 64) + 2% crepitus with patella femoral pain (foot note table 62) = 6 % WPI.
This gives a total of 6 % WPI.
The Review Panel accepted the examination report from Medical Assessor Shane Moloney, set out above.
The Review Panel accepted and adopted the findings and clinical opinions of Medical Assessor Shane Moloney, set out above.

Consideration

Schedule 2, cl 2(a) of the MAI Act, involves a determination of two issues:
(a) whether the injury (was) caused by the motor accident, and
(b) the degree of permanent impairment of the injured person that has resulted from the injury.
Having considered the submissions of the parties, the issues are:
(a) whether the left leg injury (was) caused by the motor accident, and
(b) the degree of permanent impairment of the injured person that has resulted from the left leg injury.

Causation

The Motor Accident Guidelines set out the relevant considerations in relation to causation in Part 6 specifically clauses 6.5, 6.6 and 6.7.
In Briggs v IAG Limited trading as NRMA Insurance [2022] NSWSC 372 (Briggs) Wright J confirmed that the relevant legal test in relation to causation does not require scientific certainty. It is not to be determined on the basis of scientific certainty, but on the balance of probabilities. A finding of causal connection may be open without any medical evidence at all to support it, or when the expert evidence does not rise above the opinion that a causal connection is possible.
The documentation and account provided by Mr Rillstone includes a left knee ACL reconstruction about 10 years prior to the subject injury (in or about 2008). Following the reconstruction, he returned to full and unrestricted sport, including rugby. He did not have any clinically significant symptoms prior to such subject accident.
The documentation and account provided by Mr Rillstone includes the motor accident on 30 October 2018. He was hit on the right-hand side by a motor vehicle. The driver stopped. He was taken to the Northern Beaches Hospital, admitted under orthopaedic surgeon, Dr Sam Chia. He stated he underwent three surgeries under Dr Chia, on 2 November 2018, on 22 November 2018 and on 23 May 2019.
There is an X-ray report of 13 March 2019. The findings do not appear to be of significance.
The documentation and account provided by Mr Rillstone include what could be described as a fairly good recovery post-surgery but that he does have ongoing issues and limitations, details of which are set out.
None of the parties referred the Review Panel to material that was inconsistent with the very general description set out above.
Neither party appeared to dispute that the claimant sustained a left knee injury as a result of the motor accident.
Neither party referred the panel to any material to be relied upon to the effect that the claimant had not sustained a left knee injury as a result of the motor accident.
The insurer asserted that Medical Assessor Nair did not refer to or comment on any of the material provided but then conceded that he acknowledged the claimant had undergone three surgeries with Dr Sam Chia on 2 November 2018 (MCL repair), 22 November 2018 (arthroscopy and bone grafting) and 23 May 2019 (arthroscopic ACL reconstruction with a contralateral hamstring graft).
The insurer did take issue with the “diagnosis” provided by Medical Assessor Nair.
In his report dated 25 September 2020 Dr Bodel concluded that the claimant had suffered serious injury to the left knee including multiple ligamentous injuries involving the cruciate ligaments and the medical ligament as well as a posterior horn tear of the medial meniscus.
Dr Bodel concluded that there was a direct causal link between this episode of injury while riding his pushbike and the ongoing problems with the left knee.
Dr Porteous accepted that the claimant suffered a left knee injury as a result of the accident.
Dr Smith provided the insurer with a report dated 16 November 2021. Dr Smith accepted that the claimant suffered a left knee injury as a result of the accident. Dr Smith accepted that the left knee osteoarthritis that was present prior to the accident has been “probably” made somewhat worse by the accident.
The evidence available was consistent with the motor accident having caused or contributed to the left knee injury.
We accepted that Mr Rillstone sustained left knee medial and lateral meniscal tears, patella-femoral arthritis and left knee scarring .
The evidence available was consistent with the motor accident having caused or contributed to a meniscal tear (medial and lateral), rupture of ACL and patella-femoral arthritis to his left knee.
Medical Assessor Moloney made a medical determination that the motor accident could have caused or contributed to the injury.
We accepted the medical determination of Medical Assessor Moloney that the motor accident could have caused or contributed to the injury.
Both the Medical Assessors on the Panel considered that the nature of the injury, left knee meniscal tear (medial and lateral), rupture of ACL and patella-femoral arthritis, the reported symptoms, the documented symptoms and treatment received were consistent with the injury having been caused by the accident.
We accepted, on the balance of probabilities, that the motor accident could have caused or contributed to the injury.
We accepted, on the balance of probabilities, that the test for legal causation, in relation to the motor accident and the injury was satisfied.
We accepted, on the balance of probabilities, that the motor accident did cause the injury.

The degree of permanent impairment

The claimant contends there is no error with the assessment.
The insurer in its submission of 28 January 2023 refers to the Guidelines and AMA 4 Guides. The submissions specifically consider, unilateral muscle atrophy, right knee range of motion, arthritis, ligament laxity, medial meniscus debridement and scaring.
The insurer asserted that there was no evidence to suggest the Medical Assessor performed any other tests such as for ligament laxity, muscle atrophy, gait derangement or manual muscle testing (see Parts 3.2b to 3.2d of the AMA 4 Guides).
The Review Panel considered that part of the expertise in assessing and evaluating injuries involves medical opinion in the evaluation of how the circumstances described in relation to the injury will likely impact on the claimant. That involves making an assessment of tests that are more likely to be appropriate in the assessment of impairment.
The insurer noted that despite recording the claimant’s range of motion in the left knee (consistent with utilising the range of motion method to assessment permanent impairment), Medical Assessor Nair relied on the diagnosis-based estimate method to assess the claimant’s permanent impairment arising from the left knee. The Medical Assessor did so despite not providing a specific diagnosis in respect of the left knee injuries other than “left knee multiligamentous injury”. That diagnosis is general and unspecific and does not help to understand how the expert has gone on to make two separate assessments in the left knee of 1% and 10%.
The insurer also took issue with the path of reasoning when assessing 2% impairment for scarring.
One of the issues raised by the insurer was the amount of WPI found in the combined certificate as a result of the double counting or duplication of the assessment of the left knee scarring.
Neither party took issue with both Medical Assessor Nair and Medical Assessor Curtin assessing scarring.
Neither party made submissions about how the assessment of scarring should be considered given the duplication of assessment.
Neither party made submissions about how the assessment of scarring by both Medical Assessor Nair and Medical Assessor Curtin should be dealt with in considering the assessment of Medical Assessor Nair.

Left knee (excluding Scarring)

The material provided was reviewed and evaluated.
This material had largely been considered and discussed in the various medico-legal reports.
Those medico-legal reports included an evaluation of this material.
Medical Assessor Nair reported flexion of 130 degrees in the right knee and120 degrees in the left knee, and extension of 0 degrees in the right knee and 5 degrees in the left knee.
Medical Assessor Nair found that the condition was permanent as it is unlikely to change by more than 3% in the next year.
Medical Assessor Nair then assessed a 10% permanent and then a separate 1% permanent impairment.
The claimant was assessed by Medical Assessor Anil Nair in relation to the left knee significant post-surgical scarring permanent impairment of 2%.
Medical Assessor Nair concluded the total permanent impairment was 13%.
Dr Bodel concluded that “Mr Rillstone had moderate persisting medial and anterior cruciate ligament laxity and in accordance with Table 64, on - Page 85, this constitutes a 10% Whole Person Impairment”.
Dr Bodel noted that there had also been a partial meniscectomy in the medial meniscus which attracts another 1% Whole Person Impairment from that same table.
Dr Bodel concluded that the restricted range of movement cannot be combined with those ratings and therefore the injury to the left knee is an 11% Whole Person Impairment on the basis of the Diagnosis Based Estimates.
Dr Bodel considered that the scarring was quite significant and would rate that as a 2% WPI under the TEMSKI scale.
Dr Bodel concluded that the total impairment was a 13 % WPI overall.
In response to the above assessment Dr Smith noted “Any impairment assessment should be based on the radiology, and he should have the x-rays mentioned in the paragraphs above. Using the range of motion method available in AMA 4, there is no assessable impairment in either knee, as yet.”
Dr Smith was retained by the insurer, however, the submission of the insurer did not accord with that opinion.
The insurer in its submission of 28 January 2023 refers to the Guidelines and AMA 4 Guides suggesting WPI for unilateral muscle atrophy of 1% to 2% WPI, Arthritis of 2% WPI, medial meniscus debridement of 4% WPI and scaring of 2% WPI.
The insurer in its submission of 28 January 2023 did not consider that the evidence disclosed any impairment arising from the right knee range of motion or ligament laxity.
These submissions of the insurer were consistent with the letter from NRMA of 11 January 2022.
Both of the Medical Assessors were of the view that whilst there was some variability in the assessment by the various medical practitioners that evaluated the claimant, these variabilities were relatively minor in terms of their clinical significance in the evaluation of WPI.
The claimant asserted that Medical Assessor Nair's impairment of the left knee assessed 10% WPI in keeping with Table 64, page 85 for the injury to the medial and anterior cruciate ligament. Medical Assessor Nair allowed a further 1% WPI on the basis that there had been a partial meniscectomy in the medial meniscus.
The Motor Accident Guidelines include Part 6 regulating assessment of permanent impairment.
Clause 6.1 provides that the degree of permanent impairment arising from injury caused by motor accident in accordance with Division 7.5 s 7.21 and cl 2 of schedule 2 of the MAI Act is to be assessed in accordance with these guidelines.
Clause 6.2 notes that the guidelines are based on the AMA 4 Guides. It is noted that the guidelines contain some very significant departures from that document and that undertaking an assessment requires a consideration of the guidelines in conjunction with the AMA 4 Guides.
In relation to the lower extremity clauses 6.68, 6.69, 6.70, 6.71, 6.72, 6.73, 6.74 and 6.75 provide further provisions. There are then further provisions relating to specific aspects.
In addition, Table 6.5 then provides for permissible combinations of lower extremity assessment methods.
In relation to arthritis clauses 6.90 and 6.92 make reference to Table 62 (page 80 3 AMA 4 Guides).
We accepted the findings of Medical Assessor Shane Moloney.

Ligament laxity

Dr Bodel considered there was moderate persisting medial and anterior cruciate ligament laxity and in accordance with Table 64, on page 85, this constitutes a 10% WPI.
This appears to be a similar approach to that of Medical Assessor Nair.
At the time of examination by the Review Panel, no ligament laxity was noted on testing. The WPI is based on clinical findings at that time.
We rejected the approach taken by Dr Bodel and Medical Assessor Nair because when Medical Assessor Moloney assessed the claimant, there was no ligamentous laxity remaining.

Range of motion

Clause 6.85 relates to range of motion. Specifically, that Tables 40 to 45 (page 78 AMA 4 Guides) are used to assess range of motion in the lower extremities. Where there is loss of motion in more than one direction/axis of the same joint, only the most severe deficit is rated – the ratings for each motion deficit are not added or combined. However, motion deficits arising from separate tables can be combined.
On testing range of movement flexion of the right knee was 130° with 0° extension. Left knee was 110° flexion and extension -5°. This is equivalent to a flexion contracture of 5°, which is a mild impairment of 4% WPI in Table 41.

Universal muscle atrophy

There was slight muscle wasting of the left thigh. The circumference of the lower thighs was 55cm on the right and 54cm on the left (10cm above the superior patella pole) and at the maximum circumference of the calves 47cm bilaterally. No ligament laxity was noted of either knee but there was tenderness on palpation of the patellofemoral joint with crepitus on passive movement.

Using the footnote Table 62 of AMA 4 Guides, a history of direct trauma with patellofemoral pain and crepitation on physical examination is 2% WPI.
There was significant direct trauma to his left knee causing a dislocation of the patella which causes damage to the underlying patella surface and later development of arthritic changes with pain and palpable crepitation. Following direct blow to the knee, there was resultant retropatellar crepitus.

Diagnosis based estimates

Diagnosis based estimates are included in the part. Clause 6.94 notes that section 3.2i (pages 84-88 of AMA 4 Guides) lists a number of conditions that fit a category of diagnosis-based estimates. They are listed in Table 64 (pages 85-86 of AMA4 Guides) which contain relevant footnotes.
Dr Chia in his examination report dated 22 November 2018, reported that the medial meniscus was reduced, and the anterior horn debrided as well as a peripheral tear lateral posterior horn repaired with sutures and debrided. Using Table 64, this is equivalent to a partial meniscectomy of the medial and lateral meniscus which is 4% WPI.
The Review Panel accepted that the circumstanced described in relation to the claimant fell within the terms of Table 64.
The operation report noted debridement and repair of the lateral and medial menisci which is the equivalent of a partial meniscectomy of both menisci. The knee had been made stable by surgery so residual impairment is from Tables 64 and 62 (as above).

Table 6.5 of the MAA Guidelines

However, using Table 6.5 of MAA Guidelines, it is not permissible to combine range of motion or muscle atrophy with a DRE assessment (which was obtained using AMA 4 Guides, Table 64 for the partial meniscetomies).
The final WPI is 4% WPI for partial menisectomy lateral and medial (Table 64) and 2% crepitus with patella femoral pain (foot note Table 62).
This gives a total of 6% WPI.

Left knee scarring

As noted earlier, neither party took issue with both Medical Assessor Nair and Medical Assessor Curtin assessing scarring and neither party made submissions about how the assessment of scarring should be considered given the duplication of assessment.
Neither party made submissions about how the assessment of scarring should be considered given the double counting of the scarring WPI assessment in the combined certificate.
There have been a number of recent decisions that have dealt with issues relating to the nature of the “matter” before Medical Assessors. These mostly occur in the context of a particular injury not being specifically identified or in a specific or limited injury being identified in the process.
Various provisions of the MAI Act contemplate the appointment of more than one Medical Assessor.
Pursuant to s 7.20(2) of the MAI Act the dispute can be dealt with by one or more Medical Assessors.
Pursuant to s 7.21(2) of the MAI Act impairments that result from more than one injury arising out of the same motor accident are to be assessed together to assess the degree of permanent impairment.
Pursuant to s 7.23(1) of the MAI Act, the Medical Assessor or assessors to whom a medical dispute is referred is or are to give a certificate as to the matters referred for assessment.
Section 7.23(8) of the MAI Act provides:
“The following procedure is to apply if the assessment of more than one medical assessor is required to assess whether the degree of permanent impairment of the injured person is greater than a particular percentage (not being an assessment of the degree of permanent impairment resulting from psychiatric or psychological injury)—
(a) each medical assessor is to give a certificate as to the degree of permanent impairment of the injured person resulting from the particular injury or injuries with which the medical assessor's assessment is concerned,
(b) based on the matters certified in each such certificate a medical assessor nominated by the Authority for the purpose is to make an assessment of the total degree of permanent impairment resulting from all the injuries with which those certificates are concerned and is to give a certificate (a ‘combined certificate’ ) as to that total degree of permanent impairment
…”
There is no evidence that scarring was specifically excluded from the matter referred to Medical Assessor Nair. There is no evidence that the Medical Assessor Nair did not comply with the terms of the legislation in seeking to assess scarring.
The assessment of Medical Assessor Nair in relation to the scarring resulted in a finding of the same percentage assessment as Medical Assessor Curtin.
On the material before us there is no evidence that the scarring was not an issue that Medical Assessor Nair was not obliged to assess.
To the contrary, had Medical Assessor Nair not assessed the scarring, it may have been open to the parties to contest the determination of Medical Assessor Nair on that basis.
The assessment of Medical Assessor Curtin set out in in the certificate dated 24 March 2023 was before the Review Panel. Medical Assessor Curtin identified the injury as left knee scarring, significant post-surgical scarring. Medical Assessor Curtin set out the pre-accident history, the circumstances of the injury and included at point 15 details of his examination, and on pages 4 and 5 his assessment of the scaring.
In his report dated 25 September 2020 Dr Bodel noted “ …the scarring is very significant, associated with the multiple surgical procedures and I would rate this as moderate complex surgical scarring and a 2% Whole Person Impairment under the TEMSKI scale.”
Dr Smith noted “I would concur that there is scarring in both knees, which would amount to an assessable impairment. I would have thought that a 2% whole person impairment would be the maximum one could describe to the scarring of both his knees.”
We accepted the assessment of Medical Assessor Curtin and Dr Bodel in relation to the scarring. This was consistent with the view of Dr Smith and with the view of the Review Panel.
The insurer was aware of the ability to seek to have a certificate, including a combined certificate, rectified in the context of an obvious error.
Section 7.23(9) of the MAI Act provides that if a Medical Assessor is satisfied that a certificate under this section contains an obvious error, the Medical Assessor may issue a replacement certificate to correct the error.
The assessment of Medical Assessor Curtin and the content of the certificate issued was not a matter in issue before this Review Panel.
The combined certificate issued by Medical Assessor Curtin was not a matter before this Review Panel.
Section 7.26 of the MAI Act relates to reviews and s 7.26(8) provides that if on the review of a medical assessment of a single Medical Assessor on which a combined certificate assessment is based a new certificate is issued by the review panel, the review panel is also to issue a new combined certificate to take account of the results of the review.
Noting the assessment made above in relation to WPI resulting from the left knee injury excluding scarring, the review will result in a new certificate being issued in relation to the assessment of Medical Assessor Nair.
As a consequence of that the Review Panel will be required to issue a new combined certificate to take account of the results of the review
Being aware of the assessment of Medical Assessor Curtin, and in circumstances where that assessment and the resulting certificate have not been challenged, the assessment of the resulting WPI for the left knee scarring will remain at 2%.
Again, as the WPI determined by Medical Assessor Nair in relation to the left knee scarring was the same as Medical Assessor Curtin, there is no conflict in the resulting WPI assessment of scarring.
The result being that, subject to a new combined certificate being issued without double counting of the WPI for scarring, irrespective of whether the Medical Assessment of Assessor Nair in relation to the scarring is maintained or not, the ultimate result will continue to be a determination of WPI resulting from the scarring of 2%.

CONCLUSIONS

The following injury was referred by the Commission to the Review Panel for assessment:
(a) left knee.
The Review Panel found that the following injuries were caused by the motor accident:
(a) left knee – meniscal tears, patella-femoral arthritis and flexion contracture.
The Review Panel determined the degree of permanent impairment as follows:
(a) WPI is determined by partial meniscetomy of medial and lateral menisci which is 4% WPI in Table 64. There is patella-femoral pain on compression of the patella and with the footnote of Table 62 (page 83) with direct trauma is 2% WPI. Using Table 6.5 of Guidelines, muscle atrophy and range of movement can’t be combined with DRE estimates.
The Review Panel determined the degree of permanent impairment as follows:

Body part or System

Guidelines

AMA Guidelines

Permanent

Yes/No

Current %WPI

%WPI from pre-existing or subsequent causes

%WPI due to motor accident

Left Knee

Table 64 Page 85

Yes

4%

0%

4%

Left Knee

Table 62 Page 83

Yes

2%

0%

2%

Left Knee

TEMSKI

Yes

2%

0%

2%

Neither party contended that there was any evidence to support any pre-existing or subsequent causes for WPI.
The Review Panel did not accept that there was any evidence to support any pre-existing or subsequent causes for WPI and found there was no pre-existing or subsequent causes for WPI.
Neither party contended that found that the condition was not permanent nor that it was likely to change by more than 3% in the next year.
The Review Panel found that the condition was permanent as it is unlikely to change by more than 3% in the next year.
Using the Combined Values Chart at page 322 of AMA 4 Guides, the combined permanent impairment is 8%.
Having determined that the WPI is different to that found by Medical Assessor Nair that will result in a new certificate being issued in relation to the assessment of Medical Assessor Nair.
As a consequence of that the Review Panel is also required to re-issue the combined certificate.
In the circumstances, that combined certificate will include the WPI for the scarring at 2%. It will include the WPI for the scarring at 2% by adopting either the assessment of this Review Panel or by adopting the assessment of Medical Assessor Curtin.
The combined certificate will be re-issued with the combined permanent impairment of 8%.
The Review Panel revokes the certificate dated 26 May 2023and issues a new certificate determining that:
(a) the following injuries caused by the motor accident give rise to a permanent impairment of 8% and is not greater than 10%, left leg 8%.
In considering the prior combined certificate it is noted that this included a duplication or double counting of the WPI for left knee scarring of 2% WPI.
Having revoked the certificate dated 26 May 2023 and determining that there is a need to issue a new certificate, the Review Panel is then required to issue a new combined certificate.
The Review Panel issues a new combined certificate that:
(a) the following injuries caused by the motor accident give rise to a permanent impairment of 8% and is not greater than 10%, and
(b) left leg medial and lateral meniscal tears, patella-femoral arthritis and left knee scarring 8%.

Body part or System	Guidelines AMA Guidelines	Permanent Yes/No	Current %WPI	%WPI from pre-existing or subsequent causes	%WPI due to motor accident
Left Knee	Table 64 Page 85	Yes	10%	0%	10%
Left Knee	Table 64 Page 85	Yes	1%	0%	1%
Left Knee	TEMSKI	Yes	2%	0%	2%

[2024] NSWPICMP 566

14 August 2024