Catterall v State of New South Wales (NSW Police Force)

DETERMINATION OF APPEAL PANEL
CITATION:	Catterall v State of New South Wales (NSW Police Force) [2023] NSWPICMP 425
APPELLANT:	Monica Catterall
RESPONDENT:	State of New South Wales (NSW Police Force)
APPEAL PANEL
MEMBER:	Marshal Douglas
MEDICAL ASSESSOR:	Gregory McGroder
MEDICAL ASSESSOR:	John Brian Stephenson
DATE OF DECISION:	1 September 2023
CATCHWORDS:	WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; appellant suffered injuries to her right upper extremity (elbow, wrist and thumb) and left upper extremity (wrist and thumb) due to a specific task appellant did in her employment over the course of years; appellant had bilateral trapeziectomies; the Medical Assessor (MA) assessed the appellant’s permanent impairment by reference to restricted range of movement only and made a deduction of 50% under section 323(1) for the proportion of permanent impairment due to a pre-existing degenerative condition; whether the MA ought to have included in his assessment a rating under Table 16-27 of American Medical Association’s Guides to the Evaluation of Permanent Impairment (AMA5) for the trapeziectomies; whether the MA erred by making a deduction of 50% under section 323(1); Appeal Panel held the MA erred by not including a rating under Table 16-27 as the impairment the appellant had from the trapeziectomies was different from her impairment due to restricted range of motion; Appeal Panel held that the relevant date at which to determine what the appellant’s pre-existing condition was the date she commenced the activity that resulted in her injury not the date of her injury; the Appeal Panel held that at that date the appellant’s pre-existing degenerative condition was minimal; Appeal Panel held it would be too difficult to determine the proportion to which the appellant’s permanent impairment was due to that pre-existing condition and the MA erred by not assuming, in accordance with section 323(2), that the deductible proportion for the purposes of section 323(1) is 10% as that assumption was not at odds with the evidence; Held – Medical Assessment Certificate revoked.

BACKGROUND TO THE APPLICATION TO APPEAL

On 16 June 2023 Monica Catterall, the appellant, lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr Tim Anderson, a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on 19 May 2023.
The appellant relies on the following grounds for appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (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 for 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 (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).

RELEVANT FACTUAL BACKGROUND

The appellant in a statement she signed on 15 February 2021 said that she had been working for the New South Wales Police Force, the respondent, for more than 14 years. She initially worked in a call centre until 2017, then as a PTA officer until August 2018, and then as a supervisor and senior adjudicator. She said that from approximately July 2013 she was required to use a keyboard with a “roller mouse”. She said that she needed to use both her left and right thumbs with this device and that she had to scroll and click the mouse all day with her thumb. She said that outside of her work she did not do any activities or repetitive tasks that required her to use her thumbs and elbow. She said that she started noticing pain in her thumbs and her right elbow in around 2016.
On 21 January 2020 the appellant had an X-ray done of both her hands and elbow and an ultrasound of the right elbow. Dr Geraldine Walsh, who reported on those X-rays, advised they revealed both the appellant’s hands showed osteoarthritic changes in both the first CMC articulations that were moderate on the right side and severe on the left side. Dr Walsh reported that the X-ray of the right elbow showed preserved articular surfaces and joint spaces without any significant arthritic damage. Dr Walsh said that the ultrasound of the right elbow showed findings consistent with tendinopathic change involving the common flexor tendon origin.
On 24 July 2021 orthopaedic surgeon Dr Michael Thomas performed a trapeziectomy on the appellant’s right thumb and on 14 October 2021 he performed a trapeziectomy on her left thumb.
On 22 August 2022 orthopaedic surgeon Dr Zbigniew Poplawski examined the appellant at the request of her solicitors. In a report dated 30 August 2022 Dr Poplawski advised the appellant’s solicitors that the appellant had “sustained cumulative work injuries to her neck, medial epicondyle region of the right elbow (since settled) and both hands in the form of increasing pain developing in the CMC joints of both thumbs”. Dr Poplawski noted that the appellant required surgery for both thumbs in the form of a bilateral trapeziectomy.
Dr Poplawski noted that the appellant’s ongoing symptoms required her to wear support of thumb splints. Dr Poplawski advised that “the diagnosed injuries are consistent with the reported mechanism of injury”. Dr Poplawski advised that he assessed the appellant had a whole person impairment (WPI) of 24%, which he advised comprised 8% due to her cervical spine, 10% due to her right upper extremity (consisting of her right wrist, thumb and elbow), and 8% for her left upper extremity (consisting of her left wrist and thumb).
Relying on that report of Dr Poplawski the appellant claimed compensation for permanent impairment from the respondent’s insurer.
The insurer’s solicitors then organised orthopaedic surgeon Dr Peter Dodd to examine the appellant on 26 October 2022. In a report to the respondent’s solicitors dated
4 November 2022 Dr Dodd advised that he diagnosed the appellant had exacerbation of bilateral trapeziometacarpal osteoarthritis which had been treated surgically and exacerbation of minor degenerative changes in the cervical spine. Dr Dodd advised that he did not think the appellant’s “employment duties as a non-sworn officer were the main contributing factor to her cervical spine symptoms” and that her “employment was not a substantial contributing factor to the cervical spine injury”. He advised that he did not consider “her injury to her upper extremity on either side has contributed to her cervical spine disease”. He advised that “there is no doubt severe pre-existing pathology in both hands and possibly also her cervical spine”. Dr Dodd assessed the appellant had 5% WPI due to the injury to her wrist and thumbs.
In an earlier report of 18 January 2021 to the respondent’s insurer, which followed Dr Dodd’s examination of the appellant on 12 January 2021, he advised his “diagnosis of injury” was an “exacerbation of osteoarthritis of the first carpometacarpal (trapezio-metacarpal joint) in both arms”.
On 15 December 2022 the insurer notified the appellant under s 78 of the 1998 Act that it disputed she was entitled to compensation for permanent impairment from her injury. It advised its reasons for its decision were that it did not agree that her claimed injury to her cervical spine and right elbow was “covered by workers compensation as required by s4 of the Workers Compensation Act 1987”. It advised that it did not agree that her employment was the main contributing factor to the onset of disease or to the aggravation, acceleration, exacerbation or deterioration of a disease at the neck or elbows. It advised that there was no specific incident at her work that caused injury or that her employment was a substantial contributing factor to her cervical spine injury or injury to her elbows. It advised that it did not agree she had a consequential condition “from your accepted injury as required by s4 and s9A of the Workers Compensation Act 1987”. It advised that with respect to the injury to the appellant’s bilateral thumbs and bilateral wrists that the appellant was not entitled to lump sum compensation because her accepted injury to those body parts had not resulted in more than 10% permanent impairment, which threshold her permanent impairment needed to exceed in order for her to be entitled to compensation for permanent impairment.
The appellant then registered with the Commission an Application to Resolve a Dispute (ARD) dated 21 December 2022, seeking determination of her disputed claim for compensation under s 66 of the 1987 Act for permanent impairment from her injury. The appellant particularised her injury the subject of her claim in the ARD in these terms:
“Worker injured right and left thumbs over a period of time between approximately August 2018 to June 2019. Worker’s injury was caused by repetitive use of a roller mouse to complete her desk job.”
The appellant particularised that the date of her injury was 3 June 2019.
The matter was referred to Member Karen Garner who, with the consent of the parties, made the following determination and notation:
“1. The Application to Resolve a Dispute is amended as follows:
a.     Date of Injury:
i.        Delete –
“3 June 2019”
ii. Insert –
“3 June 2019 (deemed)”
b.     In the Injury Details – Injury description:
i. Delete –
“Worker injured right and left thumbs over a period of time between approximately August 2018 to June 2019. Worker’s injury was caused by repetitive use of a roller mouse to complete her desk job.”
ii. Insert –
“Cervical spine, right upper extremity (elbow, wrist, thumb), left upper         extremity (wrist, thumb) - Worker injured body parts over a period of time between approximately August 2018 to June 2019. Worker’s injury was caused by repetitive use of a roller mouse and typing to complete her desk job and nature and conditions
of work.”
c.     In the Permanent Impairment/Pain and Suffering:
i.        Amend to read –
Date of injury:             3 June 2019 (deemed)
Systems Claimed:      (1) Cervical spine
(2) Left upper extremity (wrist, thumb)
(3) Right upper extremity (elbow, wrist, thumb)
Total WPI Percentage: 24
Total WPI Amount: $64, 220
2. Award for the respondent with respect injury to the cervical spine.
3.      The matter is remitted to the President for referral to a medical assessor for assessment as follows:
Date of injury:        3 June 2019 (deemed)
Body parts: Left upper extremity (wrist, thumb)
Right upper extremity (elbow, wrist, thumb)
Method:                   Whole Person Impairment
4. The material to be referred to the medical assessor are to include:
a.     Application to Resolve a Dispute and attachments, and
b.     Reply to Application to Resolve a Dispute and attachments.
Notations
A.      Respondent agrees that the applicant sustained injury to the right elbow as alleged.”
A delegate of the President duly referred the matter to the Medical Assessor on 6 April 2023.

MEDICAL ASSESSMENT CERTIFICATE

The Medical Assessor examined the appellant on 2 May 2023. The history recorded in the MAC included that the appellant had been working in a firearm registry for 17 years and that in 2018 she started experiencing pain over the radial side of each wrist. The Medical Assessor recorded that the appellant was referred to orthopaedic surgeon Dr Michael Thomas who identified extensive degenerative change at the trapezio-metacarpal joint of each thumb. The Medical Assessor recorded that the appellant had a surgical procedure on the right wrist in July 2021 and on the left wrist in October 2021.
The Medical Assessor set out in the MAC his findings from his examination of the appellant’s cervical spine and upper limbs. The Appeal Panel observes that neither party has raised any issue with the examination the Medical Assessor conducted or with his findings from his examination that he recorded in the MAC.
The Medical Assessor noted in the MAC that a plain X-ray of the appellant’s wrists done on 21 January 2020 revealed trapezio-metacarpal joint osteoarthritis.
Neither party contested the Medical Assessor’s assessment of the appellant’s permanent impairment due to the restricted range of movement the Medical Assessor found the appellant had in her thumbs and wrist based on the findings he made from his examination. They were, with respect to the appellant’s right upper extremity, 3% upper extremity impairment due to her wrist and 7% upper extremity impairment due to her thumb. With respect to her left upper extremity, the Medical Assessor found her upper extremity impairment was 2% with respect to her wrist and 7% with respect to her thumb.
The Medical Assessor noted that in accordance with Table 16-03 of AMA5, the upper extremity impairment he found the appellant had of her right upper extremity converted to 6% WPI, and with respect to the left upper extremity it converted to 5% WPI.
The Medical Assessor considered the appellant had substantial pre-existing degenerative changes at the carpometacarpal joint of each thumb and that a proportion of the appellant’s impairment of her upper extremity was due to that such that a deduction was required under s 323(1) of the 1998 Act. The Medical Assessor considered that deduction should be half of the impairment he found the appellant had in each of the upper extremities. He provided this explanation:
“It is very obvious that there is a substantial pre-existing degenerative condition at the carpometacarpal joint of each thumb. In cases where it is too difficult or costly to identify this more accurately, an arbitrary figure of a deduction of one-tenth is usually applied, unless this is at odds with the clinical findings. In this case I would suggest that such a deduction would be very much at odds with the underlying condition. A deduction of half is therefore applied to each side. With the right upper extremity, this reduces the impairment to 3%. On the left side, it reduces the impairment to 2.5%, which is rounded up in her favour to 3%.”
Consequently, the Medical Assessor found that the appellant had 3% WPI relating to her right upper extremity and 3% WPI relating to her left upper extremity resulting from the injury the appellant suffered. In accordance with the combined table values of AMA5, those impairments combine to 6% WPI, which is what the Medical Assessor certified the appellant’s permanent impairment to be resulting from her injury in the MAC.

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.
As a result of that preliminary review, the Appeal Panel determined that it was not necessary for the appellant to undergo a further medical examination. This is because the material before the Appeal Panel is sufficient to for the Appeal Panel to determine the appeal.

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.

SUBMISSIONS

Both parties made written submissions. They are not repeated in full, but have been considered by the Appeal Panel.
In summary, the appellant submitted that at the time she commenced her employment with the respondent in 2006 she had not suffered any previous injury or impairment that affected her upper limbs. The appellant submitted that her employment with the respondent involved constant repetitive computer keyboard and mouse use over many years which resulted in her having an aching thumb. The appellant noted that the first radiological investigation she had was on 21 January 2020 and that revealed degenerative change, but she submitted there was no contemporaneous objective evidence that she had degenerative changes when she commenced employment with the respondent.
The appellant submitted that the relevant question for determination with respect to whether a deduction should be made under s323(1) of the 1998 Act was whether she had any pre-existing impairment prior to the commencement of her employment. The appellant submitted that the Medical Assessor failed to consider or determine how many years she had the degenerative changes that the radiological investigations revealed. The appellant submitted that the Medical Assessor should have determined that in the absence of contemporaneous radiological evidence pre-dating her employment with the respondent it was difficult to determine accurately the extent of the deduction to be made under s 323(1) and the Medical Assessor should have consequently determined the deduction to be 10% of the impairment.
The appellant noted that she underwent a right trapezioctomy on 24 July 2021 and a left trapezioctomy on 14 October 2021. The appellant submitted that as a result of these surgical procedures she should have been awarded an additional 11% upper extremity impairment for each upper extremity in accordance with Table 16-27 of AMA5.
In reply, the respondent submitted that it was not relevant what “was in place or whether there was evidence of a condition prior to 2006, given that the activities that caused the injury occurred much later”. The respondent submitted that “it was not necessary for the [Medical Assessor] to address the time period with onset of symptoms when that had already been outlined by the appellant, and the Medical Assessor accepted her history”. The respondent submitted that the Medical Assessor found that there was a pre-existing condition before the activities that actually gave rise to the injury.
The respondent submitted that the Medical Assessor provided “more than adequate reasons” for making the deduction he did under s 323(1). The respondent submitted that the Medical Assessor provided a “proper medical explanation” for the deduction he made. The respondent submitted that the Medical Assessor exercised clinical skill and expertise based on the evidence to come to the opinion that the pre-existing degeneration the appellant had contributed a larger proportion of 10% to her impairment. The respondent submitted that a difference of opinion is not sufficient to establish error.
The respondent submitted that Table 16-27 is only applicable for “other disorders” and consequently has no application with respect to this matter. The respondent referred to clause 2.11 of the Guidelines which notes that s 16.7 of AMA5 provides that impairment of the upper extremity due to other disorders should only be used when other criteria have not adequately encompassed the extent of impairments and that the assessor must take care to avoid duplication of impairments. The respondent submitted that “there is nothing to suggest that a range of motion assessment did not adequately encompass the extent of the claimant’s disability or impairment”. The respondent noted that neither Dr Poplawski nor
Dr Dodd included any component under Table 16-27. The respondent noted that the Medical Assessor did not suggest that range of motion did not encompass the appellant’s impairment.

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.

Section 323

With respect to the issue of what deduction should be made under s 323(1) it is necessary to establish what the appellant’s pre-existing condition was at the “relevant date”.[1] In this case, given that the appellant’s injury arose due to a specific task she commenced in July 2013, specifically using a roller mouse, the pre-existing condition for which a deduction is to be made under s 323(1) must be a condition that was present then.[2] Saying that another way, given that the appellant’s injury occurred due to the effect that the task of using a roller mouse had on a pre-existing pathology or on her physiology over a course of time, the “relevant date” in this matter is the date on which this task commenced to have a deleterious effect, and that is July 2013.
[1] Cullen v Woodbrae Holdings Pty Ltd [2015] NSWSC 1416 at [46] (Cullen).
[2] Cullen at [47]-[58]; Craigie v Faircloth & Reynolds Pty Ltd [2021] NSWSC 1211.
In substance the appellant’s submissions on this point is that whilst the earliest radiological investigations on her hands that were done on 21 January 2020 revealed degenerative changes in the first CMC joints in each hand, it did not establish to what extent there was degeneration in her hands many years earlier and, consequently, it is too difficult to determine what deduction should be made under s 323(1). Hence, according to her,
s 323(2) should be engaged and an assumption made that the deduction under s 323(1) is 10% as that assumption is not at odds with the available evidence.
The Appeal Panel agrees with that. Indeed, bearing in mind, firstly, that the relevant date in this case at which to determine what the pre-existing condition was, is July 2013 and, secondly, that the appellant’s evidence in her statement, which is uncontradicted, is that she did not experience any pain until 2016, there is an arguable case that at the relevant date the appellant did not have any pre-existing condition and, consequently s 323(1) ought not to be engaged at all. However, that is not the case that the appellant has put to the Appeal Panel. Rather, her case is that there was degeneration existing at the relevant date, and given that is the case she puts, the Appeal Panel shall proceed on that basis.
The Appeal Panel observes that the X-ray of the appellant’s hands done on 21 January 2020 revealed that at that time there was extensive degeneration in the appellant’s first CMC joint in each hand. In the Appeal Panel’s view the degeneration revealed in that investigation was unlikely to have been as extensive in July 2013, given the appellant did not experience any symptoms until 2016. Again, the Appeal Panel considers that there is an arguable case that no inference can be drawn from that investigation that there was any degeneration in the appellant’s first CMC joint in each of her hands in July 2013, but, to repeat, that is not the case that the appellant has put to the Appeal Panel in her appeal against the MAC.
In the Appeal Panel’s view, as the appellant has submitted, the evidence in this case does not enable a conclusion to be drawn that there was extensive degeneration in her first CMC joint of each hand in July 2013. The fact that it was a further three years after July 2013 before the appellant first experienced symptoms, indicates that the degeneration was, at most, minimal at July 2013.
Given that, the Appeal Panel considers that the Medical Assessor erred by not assuming in accordance with s 323(2) of the 1998 Act that the proportion to be deducted under s 323(1) was 10%. That assumption is not at odds with the available evidence, that evidence being, firstly, that the appellant was not suffering symptoms in July 2013 when she commenced the activity that caused her injury and did not suffer symptoms for a further three years and, secondly, it cannot be inferred from the first radiological investigation done in January 2020 that the degeneration in her hands in July 2013 was other than minimal, and indeed as the Appeal Panel has observed it is arguable that based on the evidence as at the relevant date there was no degeneration.
In the Appeal Panel’s view it was not open to the Medical Assessor in the exercise of his clinical judgment to conclude that there was extensive degeneration in the appellant’s first CMC joint of each hand at the relevant date. He erred in the exercise of his clinical judgment because it did not accord with the evidence.
Further, insofar as the appellant’s impairment has been rated based on the restricted range of motion she has in her wrist and thumbs and noting that the appellant had a trapeziectomy on her right wrist in July 2021 and in her left wrist in October 2021, which substantially resolved the degeneration in her first CMC joints, the pre-existing condition now only has a modest contribution to her current impairment based upon restricted range of motion because the condition is no longer present to the extent it was at the time of injury.[3]
[3] State of New South Wales (Central Coast Local Health District) v Page [2023] NSWSC 935 at [70]-[74].

Table 16-27

The appellant contends that in accordance with Table 16-27 of AMA 5 the Medical Assessor erred by not including in his assessment a rating of 11% upper extremity impairment for each upper limb on account the trapeziectomies she had. The Appeal Panel observes that the correct figure under Table 16-27 is 10% given that a trapeziectomy falls within the description of a resection arthroplasty of a carpal bone.
The respondent refers to clause 2.11 of the Guidelines which instructs, in substance, that Table 16-27 can only be engaged when other criteria have not adequately addressed a worker’s impairment and a Medical Assessor must guard against duplicating impairments. That clause reflects the following instruction within chapter 16.7 of AMA5:
“The criteria described in this section should be used only when the other criteria have not adequately encompassed the extent of the impairments. Some of the conditions described in this section can be concurrent with each other and with decreased motion because they share overlapping pathomechanics. The evaluator must have good understanding of pathomechanics of deformities and apply proper judgment to avoid duplication of impairment ratings.”
Within chapter 16-7b of AMA5 the following instruction is also found:
“16.7b Arthroplasty
Resection arthroplasty of a joint may be carried out with or without implant replacement. Impairment ratings for the upper extremity following arthroplasty of specific joints are listed in Table 16-27 and reflect
upgraded information.
In the presence of decreased motion, motion impairments are derived separately (Section 16.4) and combined with the arthroplasty impairment (Combined Values Chart, p. 604). If the same joint presents other findings, the rules outlined on page 499 must be followed to avoid duplication of impairments. However, impairment due to arthroplasty cannot be combined with impairments due to instability, subluxation, or dislocation.”
Table 16-27 of AMA 5, as the appellant submitted, provides for a rating for a trapeziectomy, being, as the Appeal Panel has already noted resection of "carpal bone (isolated)".
In the Appeal Panel's view, these instructions allow for a rating of impairment to be made for an arthroplasty in addition to a rating being made for an impairment due to restricted range of movement of the wrists and thumbs, provided the arthroplasty has resulted in an impairment beyond that assessed by reference to the restricted range of movement. So with the case to hand, if the impairment rating based on the restriction of the appellant’s movement of her wrist and thumbs does not adequately encompass an impairment she has resulting from the resection of her trapezium of both of her hands, then an additional rating can be made under table 16-27.
The Appeal Panel notes that table 1-1 of AMA 5 provide a definition of impairment of "a loss, loss of use, or derangement of any body part, organ, system or organ function". In this case, it is the Appeal Panel's view that the structural integrity of the respondent's first CMC joint in each hand is no longer the same as they were before they were excised. In other words, the excision of the trapezium has resulted in a derangement of her wrist that impairs her in a different way to what the respondent suffers due to the limitation of movement of her wrists and thumbs consequent upon her injury. The structure of each of her wrists is no longer the same.
Given this, the Panel is of the view that the Medical Assessor both erred and did not apply the correct criteria to assess the appellant’s impairment. The appellant’s claim included compensation for impairments of the wrist and thumb of her left upper extremity and the elbow wrist and thumb of her right upper extremity. Her wrist and thumb include the trapezium and consequently any impairment she has relating to the excision of that resulting from her injury is rightfully included in an assessment of her permanent impairment she has from her injury. The fact that Dr Poplawski and Dr Dodd did not turn their mind to that only means that they made the same error as the Medical Assessor.
As mentioned, there was no challenge to the Medical Assessor’s findings from his examination and what he assessed the appellant’s upper extremity impairment to be as a consequence of the restriction of movement she has of her wrist and thumbs. With respect to the right upper extremity the Medical Assessor assessed she had 3% upper extremity impairment due to the restricted range of motion of her wrist and 7% upper extremity impairment due to the restricted range of motion she had of her thumb. To that 10% upper extremity impairment should be combined for the trapeziectomy in accordance with table 16-27. When that is done 19% upper extremity impairment is the result. That converts to 11% WPI in accordance with the combined value chart at page 604 of AMA5. From that is to be deducted, for the reasons the Appeal Panel has already explained, 10% in accordance with
s 323(1) such that the result is that the appellant has 10% WPI relating to her right upper extremity as a result of her injury.
With respect to the left upper extremity the Medical Assessor assessed the appellant had 2% upper extremity impairment relating to her wrist and 7% upper extremity impairment relating to her thumb. In accordance with table 16-27 10% upper extremity impairment should be combined with that for the trapeziectomy the appellant had. When that is done 18% upper extremity impairment is the result. That converts to 11% WPI in accordance with table 16-3 of AMA5. From that for reasons previously explained, 10% is to be deducted in accordance with s 323(1) with the result being that the appellant has 10% WPI relating to her left upper extremity from her injury. Her permanent impairment relating to her right upper extremity when combined with the permanent impairment from her left upper extremity, in accordance with the combined values chart, amounts to 19% WPI.
For these reasons, the Appeal Panel has determined that the MAC issued on 19 May 2023 should be revoked, and a new MAC should be issued. The new certificate is attached to this statement of reasons.

PERSONAL INJURY COMMISSION

APPEAL PANEL

MEDICAL ASSESSMENT CERTIFICATE

Injuries received after 1 January 2002

Matter number:	W225/23
Applicant:	Monica Catteral
Respondent:	State of New South Wales (NSW Police Force)

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 Tim Anderson and issues this new Medical Assessment Certificate as to the matters set out in the Table below:

Table - whole person impairment (WPI)

Body Part or system	Date of Injury	Chapter, page and paragraph number in WorkCover Guides	Chapter, page, paragraph, figure and table numbers in AMA 5 Guides	% WPI	Proportion of permanent impairment due to pre-existing injury, abnormality or condition	Sub-total/s % WPI (after any deductions in column 6)
Right upper extremity (elbow, wrist, thumb)	03/06/2019 (deemed)	Chapter 3	P 467 F 16-28 P 469 F 16-31 P 456 F 16-12 P 457 F 16-15 P 459 T 16-08a, 08b and 09 P 438 T 16-01 P 439 T 16-02 and 03 P 506 T16-27	11%	1/10	10%
Left upper extremity (wrist, thumb)	03/06/2019 (deemed)	Chapter 3	P 467 F 16-28 P 469 F 16-31 P 456 F 16-12 P 457 F 16-15 P 459 T 16-08a, 08b and 09 P 438 T 16-01 P 439 T 16-02 and 03 P 506 T16-27	11%	1/10	10%
Total % WPI (the Combined Table values of all sub-totals)					19%

[2023] NSWPICMP 425

1 September 2023