Viluan v MQ Health Pty Ltd

CERTIFICATE OF DETERMINATION OF MEMBER
CITATION:	Viluan v MQ Health Pty Ltd [2022] NSWPIC 376
APPLICANT:	Cynthia Viluan
RESPONDENT:	MQ Health Pty Ltd
MEMBER:	Rachel Homan
DATE OF DECISION:	13 July 2022
CATCHWORDS:	WORKERS COMPENSATION - Claim for costs of and incidental to bilateral carpal tunnel release surgeries; injury disputed; applicant relied on both section 4(b)(i) and (ii) of the Workers Compensation Act 1987 (1987 Act); work as a sterilising technician involved repetitive manual handling; main contributing factor; whether evidence as to the nature and conditions of employment adequate; whether barred from recovering compensation pursuant to sections 254 and 261 of the Workplace Injury Management and Workers Compensation Act 1998; Held – the weight of medical evidence indicated that the carpal tunnel syndrome was constitutional; treating doctor evidence that condition exacerbated by repetitive work accepted; AV v AW and State Transit Authority v El-Achi applied; applicant sustained an injury pursuant to section 4(b)(ii) of 1987 Act; deemed date of injury applies pursuant to section 16 of 1987 Act; no bar to the recovery of compensation; proposed surgeries are reasonably necessary as a result of the injury.
DETERMINATIONS MADE:	1. The applicant sustained an injury to her bilateral wrists and hands pursuant to s 4(b)(ii) of the Workers Compensation Act 1987. 2. The staged bilateral carpel tunnel release surgeries proposed by Dr Simon Chan are reasonably necessary as a result of the injury. 3. The applicant is not barred from recovering compensation by ss 254 or 261 of the Workplace Injury Management and Workers Compensation Act 1998.
ORDERS MADE:	1. The respondent to pay the costs of and incidental to the proposed surgeries pursuant to s 60 of the Workers Compensation Act 1987.

STATEMENT OF REASONS

BACKGROUND

Ms Cynthia Viluan (the applicant) was employed by MQ Health Pty Ltd (the respondent) as a sterilising technician at Macquarie University Hospital.
The applicant claims that she sustained an injury to her bilateral wrists and hands in the nature of carpal tunnel syndrome due to the nature and conditions of her employment, which required repetitive wrist movements, repetitive heavy lifting and carrying, repetitive pulling and pushing of trolleys and washing instruments by hand.
The applicant said she first noticed symptoms in around February 2020. The applicant completed a claim form seeking compensation in respect of the injury on 22 March 2021.
On 12 May 2021, the applicant’s orthopaedic surgeon, Dr Simon Chan, recommended that the applicant undergo staged bilateral carpal tunnel releases.
Liability to pay compensation was disputed in a notice issued pursuant to s 78 of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act) on
20 July 2021.
The decision to dispute liability was maintained in a notice issued on 10 November 2021 following internal review pursuant to s 287A of the 1998 Act.
The present proceedings were commenced by an Application to Resolve A Dispute (ARD) lodged on 11 March 2022 in the Personal Injury Commission (the Commission). The applicant seeks compensation pursuant to s 60 of the Workers Compensation Act 1987 (the 1987 Act) for the costs of and incidental to the surgeries proposed by Dr Chan.

PROCEDURE BEFORE THE COMMISSION

The parties appeared for conciliation conference and arbitration hearing on 14 June 2022. The proceedings were conducted on the Microsoft Teams platform. The applicant was represented by Mr Dewashish Adhikary of counsel, instructed by Ms Rabia Gil. The respondent was represented by Mr Ross Hanrahan of counsel, instructed by Ms Jennifer Gair. A representative from the insurer was also present.
I am satisfied that the parties to the dispute understand the nature of the application and the legal implications of any assertion made in the information supplied. I have used my best endeavours in attempting to bring the parties to the dispute to a settlement acceptable to all of them. I am satisfied that the parties have had sufficient opportunity to explore settlement and that they have been unable to reach an agreed resolution of the dispute.

ISSUES FOR DETERMINATION

The parties agree that the following issues remain in dispute:
(a) whether the applicant sustained an injury to her bilateral wrists and hands pursuant to s 4 of the 1987 Act, as alleged;
(b) whether the proposed bilateral carpel tunnel release surgeries are reasonably necessary as a result of injury pursuant to s 60 of the 1987 Act; and
(c) whether ss 254 and/or 261 of the 1998 Act operate to bar the recovery of compensation.

EVIDENCE

Documentary Evidence

The following documents were in evidence before the Commission and considered in making this determination:
(a)    ARD and attached documents;
(b)    Reply and attached documents;
(c)    documents attached to an Application to Admit Late Documents lodged on
24 May 2022 by the applicant;
(d)    document attached to an Application to Admit Late Documents lodged on
6 June 2022 by the respondent.
Neither party applied to adduce oral evidence or cross examine any witness.

Applicant’s evidence

The applicant’s evidence is set out in a written statement made by her on 4 March 2022.
The applicant commenced work as a full-time sterilising technician with the respondent in or about September 2012. Prior to the injury, the applicant had no symptoms in either of her hands or wrists.
In or around February 2020, the applicant started experiencing intermittent numbness and pain in her hands. Over the next few months, the symptoms progressively got worse. The applicant would often wake at night due to worsening pain and numbness in her hands and tingling through her fingers up to her elbows.
On 17 September 2020, the applicant consulted her general practitioner, who referred the applicant for a bilateral wrist ultrasound and steroid injections.
The applicant underwent injections to both wrists in September 2020 and experienced some relief. Over the next few months, the applicant continued with treatment as recommended by her general practitioner.
On 26 February 2021, the applicant was assigned work in the decontamination area for a nightshift without any job rotation. The work involved pushing heavy trolleys, washing and scrubbing instruments and heavy lifting. By the time the applicant finished her shift, she was experiencing severe pain and numbness in her hands. The applicant’s symptoms were worse compared to what she had experienced before the steroid injections.
The applicant’s pain became unbearable and her symptoms constant over the following weeks. The applicant would stop and dangle her hands at work to relieve the symptoms in order to be able to get on with work.
On 19 March 2021, the applicant consulted her general practitioner and reported her worsening symptoms. The applicant was now also experiencing pain in her right thumb and last three fingers on her right hand. The shooting pain in the applicant’s hands was aggravated by any driving, writing or typing. The applicant was referred for an ultrasound of both wrists.
On 23 March 2021, the applicant notified her employer of her carpal tunnel syndrome and lodged a workers compensation claim.
On 24 March 2021, the applicant was referred to hand and wrist surgeon, Dr Simon Chan. The applicant saw Dr Chan on 7 April 2021 and reported experiencing temporary relief from injections six months earlier. The applicant’s symptoms were now constant. The applicant’s fingers were constantly swollen and stiff and she experienced numbness in her hands at work.
The applicant was referred for nerve conduction studies and hand therapy and was advised to wear night splints.
On 12 May 2021, the applicant returned to Dr Chan with her nerve conduction study results. Dr Chan recommended the applicant undergo bilateral carpal tunnel release surgeries.
The applicant continued to engage in conservative treatment including cortisone injections to her wrists. The applicant continued to struggle with ongoing pain and discomfort.
The applicant noted that the request for surgery had been declined. The applicant disagreed that her symptoms did not occur at work. The applicant said she experienced pain, numbness and discomfort in her hands and wrists at work and would often stop what she was doing to dangle her hands to alleviate the discomfort. The applicant said she only began to experience pain and discomfort in her wrists as a result of the nature and duties of the job. The applicant did not suffer any symptoms in her wrists before the work injury

Dr Chan

Orthopaedic, hand and wrist surgeon, Dr Simon Chan, prepared a report for the applicant’s general practitioner on 7 April 2021 in which he recorded a history as follows:
“Cynthia presents with sensory symptoms affecting both hands. Symptoms started in early 2020, worse on the left side. She had a corticosteroid injection in September. It gave her benefit for around 6 months. Symptoms have subsequently returned and been constant for around 1 month. She has ongoing paraesthesia and pain. She finds her fingers are swollen and stiff in the morning. She has numbness whilst at work, causing her to stop and dangle her hands for relief.”
Dr Chan recorded his clinical findings and diagnosed bilateral carpal tunnel syndrome, commenting:
“Cynthia has bilateral carpal tunnel syndrome. Given her age and gender, it is probably constitutional. However, I believe it is exacerbated by her work, which involves repetitive heavy lifting. Her symptoms are relatively severe. I have referred her for baseline nerve conduction studies. She will also see hand therapy for bilateral night splints and nerve gliding exercises. I will see her after she has had her nerve studies.”
Dr Chan prepared a report on 12 May 2021 in which he said the applicant’s nerve conduction studies confirmed the clinical diagnosis of severe carpal tunnel syndrome, worse on the right.
Dr Chan said the applicant required bilateral carpal tunnel releases and suggested endoscopic releases to assist the applicant to return to work faster. Dr Chan considered that a return to pre-injury duties would take around eight weeks. An estimate for the surgery was provided on the same date.
On 11 July 2021, Dr Chan, prepared a report for the insurer. Dr Chan indicated that the applicant had no pre-existing degenerative conditions contributing to her carpal tunnel syndrome. Asked whether employment was a “substantial contributing factor” to the injury, Dr Chan responded:
“I believe that Ms Viluan has constitutional or idiopathic bilateral carpal tunnel syndrome. I also believe that her employment is a significant contributing factor due to nature of her work duties, namely repetitive heavy lifting.”
Dr Chan said that it was probable but not definite that the applicant would have developed carpal tunnel symptoms at some time, regardless of her employment.

Associate Professor Vagholkar

The applicant relies on a report, dated 31 March 2022, prepared for her solicitor by a general practitioner, A/Prof Sanjyot Vagholkar. A/Prof Vagholkar said she had not consulted with the applicant but had prepared the report based on the medical records of the applicant’s usual general practitioner who was no longer employed at the practice.
The applicant first consulted the practice on 19 March 2021 giving a history of pins and needles in both hands and painful fingers. The applicant had consulted another general practitioner in 2020 who gave a diagnosis of carpal tunnel syndrome. The applicant was noted to work in a job that involved lifting.
Asked whether the injury was a result of the nature and conditions of the applicant’s employment, A/Prof Vagholkar stated:
“Based on the medical consultations with Dr Wang that I have reviewed and the various specialist’s reports, I believe the nature of her work exacerbated the condition in March 2021. Lifting and tasks related to sterilising supplies would put stress on the hands and wrists, thus impacting the median nerve and carpal tunnel, and may not have allowed adequate rest to allow symptoms to settle.”
A/Prof Vagholkar agreed that surgical management as proposed by Dr Chan was an appropriate course of action.

Dr Lai

The applicant relies on a medicolegal report prepared by general, plastic and reconstructive surgeon, Dr Min Fee Lai, dated 19 October 2021.
Dr Lai recorded that the applicant’s work involved repetitive motions of her hand, wrist, elbow and shoulder joints and lifting of heavy instrument trays weighing between 5 and 10 kg:
“Mrs Viluan has to clean the instruments by manual washing and brushing prior to placing them in the instrument trays; and then wrapping these trays. These trays are then loaded into the autoclave for sterilisation. The action of loading the heavy trays would involve hyper extension of her wrists by gripping the ends of each tray as it is loaded into the autoclave. Following sterilisation calling, the trays are then unloaded with use of the gripping handles. The unloading action would also involve a hand gripping action with the wrists in extension and ulnar deviation. Mrs Viluan informs me that over an eight hour day there would be at least 100, if not more trays that would be loaded and unloaded by her.”
In December 2019, the applicant began to experience intermittent paraesthesia. In early 2020, the applicant started to experience pain in both wrists radiating proximately along the forearm to the elbows and shoulders. The applicant experienced decreasing grip strength, especially at the right. The symptoms would also come on at night causing sleep disturbance as well.
Dr Lai took a history of the applicant’s treatment and Dr Chan’s recommendation for surgery. It was noted that the applicant was still experiencing constant paraesthesia, delayed thermal sensation, poor grip strength and manual dexterity issues. The applicant experienced episodes of pain, radiating from the wrists to her elbows and shoulders. Steroid injections had helped with regard to the intensity of this pain. The applicant was performing modified duties.
Dr Lai reviewed an ultrasound dated 23 March 2021 and performed a physical examination via video link.
Dr Lai diagnosed bilateral carpal tunnel syndrome.
Asked whether work was the main contributing factor to the development of the bilateral carpal tunnel syndrome, Dr Lai responded in the affirmative:
“I have detailed her job description in my report… Basically, it involves repetitive forceful gripping actions of both hands with repetitive wrist movements at the extremes of their ranges (hyper extension with ulnar deviation). I am of the opinion that these repetitive extreme wrists actions have been the main contributing factor to the development of her bilateral carpal tunnel syndrome.”
Dr Lai expressed the opinion that the contraction of the disease injury resulted from the applicant’s work and referred to articles by A/Prof Bruce Connolly and Dr John McKessar in support of his conclusion. Dr Lai did not consider the condition was pre-existing.
Dr Lai expressed the view that the applicant’s condition would worsen without surgical decompression of the carpal tunnel. The surgery proposed by Dr Chan was reasonable and necessary. The applicant had failed conservative treatment and her only other option was surgical decompression.
Dr Lai was asked to comment on the opinions given by the medicolegal expert qualified by the respondent, Dr Masson. Dr Lai expressed disagreement with Dr Masson’s opinion, stating:
“It is my opinion that he has not taken into consideration the job description that has been provided by Mrs Viluan to me, which would indicate that her bilateral carpal tunnel syndrome is work-related. Your client does not have obesity, hypothyroidism or diabetes is predisposing factors to the occurrence of carpal tunnel syndrome.
The activities of daily living a normal life does not involve the repetitive movements of the wrists as she has in her work as a hospital assistant in the sterilisation department at Macquarie Hospital.”

Dr Masson

The respondent relies on medicolegal reports prepared by hand and plastic surgeon,
Dr James Masson, dated 21 June 2021 and 26 April 2022.
In his first report, Dr Masson took a history of the onset of symptoms in February 2020. The applicant underwent steroid injections which gave her complete relief for about six months. The symptoms had returned and were now the same as they were prior to the injections.
Dr Masson recorded that the applicant had been a sterilising technician for nine years, working a 38 hour week. The job involved heavy lifting of orthopaedic trays, pushing and pulling trolleys and handwashing of instruments.
Dr Masson diagnosed bilateral carpal tunnel syndrome. On the causal relationship to employment, Dr Masson gave the opinion:
“Mrs Viluan’s symptoms occur almost entirely at night and first thing in the morning, i.e., when she is not at work. She has been working as a sterilising technician for 9 years but only developed symptoms 15 months ago. If her work as a sterilising technician had been the cause of her carpal tunnel syndrome, the symptoms should have come on much earlier than this.”
Dr Masson agreed that the surgery was reasonably necessary but said it was not related to a work injury:
“As outlined above, I believe that Mrs Viluan has constitutional carpal tunnel syndrome as seen in the vast majority of the population. She has been doing the same job for eight years before her symptoms commenced so I do not believe that there is a cause and effect relationship. In his letter of 07 April 2021, Dr Chan has stated, ‘Given her age and gender, it is probably constitutional’.”
In his supplementary report, Dr Masson was asked to comment on Dr Lai’s report.
Dr Masson said he remained of the view that the applicant’s bilateral carpal tunnel syndrome was unrelated to her employment:
“Ms Viluan describes the classic symptoms of the progression of carpal tunnel syndrome. The symptoms start off as intermittent numbness and then, with time, progress to the point where the numbness becomes constant. As outlined in my initial report, Ms Viluan was working in exactly the same occupation for almost eight years before her symptoms commenced. If her work as a sterilising technician at Macquarie University Hospital was the cause of her carpal tunnel syndrome, it should have occurred very early on in her employment and not eight years afterwards. Carpal tunnel syndrome is not a cumulative disorder. It does not build up over time and then manifest.”
Dr Masson noted the description of the applicant’s employment recorded by Dr Lai and expressed the view that the applicant’s work was insufficiently repetitive to be causative of her condition:
“Dr Lai has noted that over an eight-hour day, there would be at least 100 trays that would be loaded and unloaded by her. 100 trays loaded and unloaded over an eight-hour day would be 12.5 trays per hour or approximately one tray every five minutes. I agree that Ms Viluan’s job is repetitive, but one action every five minutes is not the sort of repetition required mechanically to be causative of carpal tunnel syndrome. There are workers on assembly lines who perform the same actions hundreds to thousands of times per hour which is far more likely to be conducive to carpal tunnel syndrome than what Dr Lai has described that Ms Viluan performs in her work.”
Dr Masson said the articles referred to by Dr Lai were published in a journal aimed at general practitioners rather than specialist surgeons. The articles set out the opinions of two doctors and referred to a number of papers that suggested work “might” be causative of carpal tunnel syndrome. Dr Masson said other papers referenced stated quite vehemently that carpal tunnel syndrome had nothing to do with occupation and was not related to repetitive movement.
Dr Masson said it was irrelevant that the applicant did not have obesity, hypothyroidism or diabetes. Carpal tunnel syndrome was a very common condition affecting otherwise healthy people through all ranges of life, but predominantly in middle-aged years.

Submissions

The Commission has been assisted by the submissions of Mr Adhikary and Mr Hanrahan. Those submissions were recorded and have not been reproduced in detail but are summarised below.

Applicant’s submissions

The applicant submitted that the dispute by reference to ss 254 and 261 of the 1998 Act was misconceived. The dispute notices suggested that the respondent had proceeded on the basis that there was a frank injury in 2020. The evidence and pleadings suggested rather that the applicant had sustained a disease injury. For the purposes of ss 15 and 16 of the 1987 Act, the correct date of injury was the date of claim. The applicant referred to the authorities in Stone v Stannard Brothers Launch Services Pty Ltd[1]and Gow v Patrick Stevedores[2].
[1] [2004] NSWCA 277.
[2] [2002] NSWCC 60.
The applicant described symptoms in her hands and wrists including pain, numbness and discomfort experienced at work.
Dr Lai took an employment history that was consistent with the applicant’s statement. Dr Lai noted the mechanics of the applicant’s duties and considered how they affected the relevant body parts. Dr Lai considered the applicant’s duties were the main contributing factor to the diagnosis and referenced studies in support of his opinion. Dr Lai considered that Dr Masson had not paid sufficient regard to the applicant’s duties.
The applicant noted that the clinical records made reference to difficulties at work due to pain and weakness in the hands and needing to avoid heavy lifting at work. The SIRA certificates of capacity diagnosed a work-related injury.
The applicant submitted that sufficient evidence had been provided of a s 4(b)(i) injury. Noting, however, Dr Chan’s opinion that the condition was probably constitutional but exacerbated by work, the applicant submitted in the alternative that the injury was consistent with s 4(b)(ii) of the 1987 Act. Referring to the decision in Federal Broom Co Pty Ltd v Semlitch[3], the applicant submitted that the evidence suggested a pathological and symptomatic worsening of the applicant’s condition due to work. Dr Chan, in seeking approval for the surgery, considered that the need for surgery was causally related to work.
[3] [1964] HCA 34.
Although Dr Chan had used the language of “substantial contributing factor” in response to the question asked of him, his opinion was consistent with s 4(b)(ii). Similarly, the evidence of A/Prof Vagholkar was consistent with there being one main contributing factor. The applicant referred to AV v AW[4] and submitted that it was necessary for the Commission to consider the lay, treating and medicolegal evidence. The respondent had not produced cogent evidence of any other main contributing factor.
[4] [2020] NSWWCCPD 9.
The applicant noted that Dr Masson had made a consistent diagnosis but disagreed with
Dr Lai on the causal relationship to employment. Dr Masson took the view that the applicant’s symptoms occurred almost entirely at night and first thing in the morning. In this regard Dr Masson’s history did not provide a fair climate for his opinion. The applicant described symptoms occurring at work affecting her capacity for work.
Dr Masson had proceeded on the understanding that the applicant was alleging a frank injury. In doing so, he only considered the development of the condition, and not an injury for the purposes of s 4(b)(ii).
In his supplementary report, Dr Masson appeared to be taking on the role of an advocate.
Dr Masson’s comparison between the applicant’s duties and those of other workers was irrelevant.

Respondent’s submissions

The respondent rejected any suggestion that Dr Masson had not provided an independent opinion. Dr Masson was simply placing his observations in a scientific context. By comparison, Dr Lai talked about what “would have” happened or occurred at work as distinct from what the applicant actually said in her statement.
The applicant’s evidence lacked specificity as to her actual duties. No reference was made to the weights of the trays or trolleys being carried and pushed.
The applicant’s best case was that employment had aggravated her condition, however, it was necessary for the applicant to establish that work was the main contributing factor to the aggravation. On the applicant’s own case, her age and gender were alternative causes and the main factors to the condition. No evidence had been provided as to the applicant’s weight or body mass index. The medical evidence made reference to the applicant engaging in gardening activities. Activities such as writing and driving were also said to exacerbate the condition. It was unclear where in the causative hierarchy all of those factors fit in. The applicant’s evidence was notable for the absence of specifics about the extent of her gardening and other activities.
The respondent submitted that the evidence supplied by the applicant was totally inadequate. The Commission was being expected to make up for the defects and errors in the applicant’s case. The applicant provided no detail as to the weights, volumes, postures and involvement of her hands in her work activities. No evidence was provided as to the duration of the applicant’s tasks, her ability to pace herself or the rotation of duties. The respondent submitted that the evidence was unsatisfactory and the Commission would not be satisfied that the applicant’s work was repetitive or heavy.
With regard to the date of injury, the respondent submitted that the date of claim was only relevant if there was no incapacity or death. The applicant failed to make any submissions regarding capacity. In the circumstances, the Commission was unable to rely on the date of claim as the deemed date.
The lack of satisfactory evidence and the delay in bringing the claim prejudiced the respondent in responding to the claim. The respondent submitted that ss 254 and 261 applied.
The respondent noted Dr Masson’s opinion that the applicant had been doing the same job for eight years before her symptoms commenced. The condition was not cumulative. The respondent submitted that Dr Masson had provided a logical argument that employment was not a contributing factor to the condition.
In his supplementary report, Dr Masson provided a much more detailed explanation of why work was not the main contributing factor. The applicant’s work was not sufficiently heavy or repetitive. Dr Masson gave the opinion that the reference material relied on by Dr Lai lacked scientific weight. Multiple other scientific papers suggested carpal tunnel syndrome was not related to occupation.
Dr Masson said the evidence failed to establish a causal relationship to work. The condition was common and the relevance of the other causative factors remained unclear on the applicant’s evidence.

Applicant’s submissions in reply

The applicant submitted that the respondent had not previously notified its concerns with regard to the specifics of the applicant’s evidence as to her work duties. No explanation had been provided as to why evidence as to the applicant’s duties had not been adduced by the respondent.
Dr Chan was aware of the applicant’s gardening. Although he accepted that it might have contributed to the applicant’s condition, Dr Chan did not indicate that anything other than employment was the main contributing factor to the condition.
In submitting that ss 254 and 261 of the 1998 Act applied, the respondent failed to deal with the reasonable excuse provisions.
The applicant submitted that Dr Masson had not grappled with the fact that the applicant was performing repetitive employment duties at the time she experienced an onset of symptoms.

FINDINGS AND REASONS

Section 9 of the 1987 Act provides that a worker who has received an “injury” shall receive compensation from the worker’s employer. The term “injury” is defined in s 4 of the 1987 Act as follows:
“4 Definition of ‘injury’
In this Act:
injury:
(a)     means personal injury arising out of or in the course of employment,
(b)     includes a disease injury, which means:
(i) a disease that is contracted by a worker in the course of employment but only if the employment was the main contributing factor to contracting the disease, and
(ii) the aggravation, acceleration, exacerbation or deterioration in the course of employment of any disease, but only if the employment was the main contributing factor to the aggravation, acceleration, exacerbation or deterioration of the disease, and
(c)     does not include (except in the case of a worker employed in or about a mine) a dust disease, as defined by the Workers’ Compensation (Dust Diseases) Act 1942, or the aggravation, acceleration, exacerbation or deterioration of a dust disease, as so defined.”
There is no medical dispute in the present case that the applicant has sustained bilateral carpal tunnel syndrome. The primary dispute between the parties, relates to the causal relationship between that condition and the applicant’s employment. The applicant relies on an injury for the purposes of s 4(b) in the nature of either a contraction of a disease or an aggravation, acceleration, exacerbation or deterioration of a disease. In both cases, the applicant is required to establish that employment was “the main contributing factor” to the injury.
In AV v AW[5]at [65]-[78] Snell DP considered a number of authorities on s 4(b) and said:
“It follows that the test of ‘main contributing factor’ involves consideration of whether there were competing causal factors (both work and non-work related) of the aggravation, and whether on a consideration of relevant causal factors the employment represented the main contributing factor. The following may be taken from the above:
(a) The test of ‘main contributing factor’ in s 4(b)(ii) is more stringent than that in s 4(b)(ii) in its previous form, which applied in conjunction with the test in s 9A. There will be one ‘main contributing factor’ to an alleged aggravation injury.
(b) The test of ‘main contributing factor’ is one of causation. It involves consideration of the evidence overall, it is not purely a medical question. It involves an evaluative process, considering the causal factors to the aggravation, both work and non-work related. Medical evidence to address the ultimate question of whether the test of ‘main contributing factor’ is satisfied is both relevant and desirable. Its absence is not necessarily fatal, as satisfaction of the test is to be considered on the whole of the evidence.
(c) In a matter involving s 4(b)(ii) it is necessary that the employment be the main contributing factor to the aggravation, not to the underlying disease process as a whole.”
[5] [2020] NSWWCCPD 9.
For the purposes of s 4(b)(i), the applicant relies predominantly on the opinion of Dr Lai.
Dr Lai took an account of the applicant’s duties and was persuaded that repetitive forceful gripping actions and repetitive wrist movements at the extremes of their ranges involved in those duties were the main contributing factor to the development of the bilateral carpal tunnel syndrome.
Weighing against Dr Lai’s expert opinion are the medicolegal reports of Dr Masson. In his first report, Dr Masson did not appear to engage to any great extent with the applicant’s particular duties, relying predominantly on his view that the symptoms would have developed sooner had the applicant’s work been the cause of the carpal tunnel syndrome. Dr Masson also took a history that symptoms were not experienced during work, which is inconsistent with the applicant’s statement evidence and the history provided elsewhere.
Dr Masson maintained his opinion in his supplementary report, but did engage to a greater extent with the applicant’s work duties and Dr Lai’s assessment of them.
Dr Masson did not accept that the applicant’s work was sufficiently repetitive to be causative of carpal tunnel syndrome. The scientific weight of the articles on which Dr Lai relied was contrasted unfavourably with a number of papers in which the opinion was vehemently expressed that carpal tunnel syndrome has nothing to do with occupation and repetitive movement.
The medicolegal opinion of Dr Masson receives support from the applicant’s treating surgeon, Dr Chan and the general practitioner, A/Prof Vagholkar. Neither of those doctors was persuaded that the applicant’s employment was the main contributing factor to the contraction of the bilateral carpal tunnel syndrome. Dr Chan, for example, considered that the condition was probably idiopathic or constitutional given the applicant’s age and gender.
The medical evidence before the Commission, therefore, weighs against a finding the applicant sustained injury for the purposes of s 4(b)(i) of the 1987 Act.
The applicant relies, in the alternative, on an injury pursuant to s 4(b)(ii) of the 1987 Act.
The applicant’s medicolegal expert, Dr Lai did not provide an opinion consistent with an injury pursuant to s 4(b)(ii). That is because Dr Lai formed the opinion that the condition itself was caused by the nature and conditions of the applicant’s employment.
Dr Masson does not appear to have turned his mind to the question of whether there was an aggravation, acceleration, exacerbation or deterioration of the bilateral carpal tunnel syndrome to which employment was the main contributing factor. Rather, Dr Masson’s attention has been directed to the genesis of the condition itself.
Both Dr Chan and A/Prof Vagholkar have, however, provided opinions indicating that the bilateral carpal tunnel condition was exacerbated by the applicant’s work. Dr Chan said the applicant’s condition would have been exacerbated by her work involving repetitive heavy lifting, noting the applicant’s relatively severe symptoms. A/Prof Vagholkar agreed that the nature of the applicant’s work exacerbated the applicant’s condition in March 2021.
The respondent’s submissions suggest that the Commission would hesitate to accept, on the opinions given by Dr Chan and A/Prof Vagholkar, that work was the main contributing factor to an exacerbation of the applicant’s bilateral carpal tunnel syndrome. In particular, the level of detail provided by the applicant as to the nature and conditions of her employment, by reference to weights, volumes, duration and postures was criticised as inadequate by the respondent.
Whilst there may have been scope to provide more specifics, I accept that the applicant has provided a reasonably thorough account of her work duties. The applicant’s account is uncontradicted. Whilst it is not clear what level of detail had been provided to Dr Chan as to the nature of the applicant’s work duties, it is relevant to note that the applicant’s duties involved sterilising medical equipment in a hospital setting. As an orthopaedic, hand and wrist surgeon, Dr Chan would be expected to have a reasonable understanding of what the applicant’s duties involved. I am satisfied that Dr Chan had a sufficiently complete understanding of the applicant’s work duties so as to provide a proper foundation for his opinion on causation.
The respondent correctly notes that in order to discharge her onus, the applicant is required to establish that employment is the main contributing factor to the exacerbation of the applicant’s condition. In this regard, Dr Chan has not used the language of s 4(b)(ii) in expressing his opinion that employment was “a significant” contributing factor in the report dated 11 July 2021. The language used by Dr Chan in this report does, however, appear to respond to the questions asked of him by the insurer. The failure of Dr Chan or
A/Prof Vagholkar to express an opinion on “the main contributing factor” is not, however, fatal to the applicant’s case.
As Roche DP said in State Transit Authority v El-Achi[6] at [72]:
“That a doctor does not address the ultimate legal question to be decided is not fatal. In the Commission, an Arbitrator must determine, having regard to the whole of the evidence, the issue of injury, and whether employment is the main contributing factor to the injury. That involves an evaluative process.”
[6] [2015] NSWWCCPD 71.
The evidence before me does suggest that the applicant experienced an intensification or exacerbation of symptoms when engaging in activities outside of work including gardening, driving, writing and typing. The applicant also described experiencing particularly intense symptoms at night and in the morning.
The applicant’s evidence and the histories provided to the doctors do, however, refer to numbness and pain whilst at work, causing the applicant to stop work and dangle hands for relief.
Significantly, A/Prof Vagholkar has explained that the lifting and repetitive tasks relating to sterilising supplies would have put stress on the applicant’s hands and wrists and impacted the median nerve and carpal tunnel. The performance of the applicant’s duties on a full-time basis may not have allowed adequate rest to allow the applicant’s symptoms to settle. It is on this basis that A/Prof Vagholkar explained the exacerbation of the applicant’s condition in March 2021.
Intermittent bilateral carpal tunnel symptoms were first noticed in December 2019 and early 2020. The applicant initially received treatment with injections which she found beneficial and she continued to work. The evidence indicates, however, that over time, the applicant’s symptoms returned and became more constant. The applicant described a particular intensification of her symptoms following a nightshift on 26 February 2021. At the end of that shift, the applicant described severe pain and numbness in her hands, worse than she had experienced before the steroid injections.
Although Dr Lai’s report does not directly support a finding for the purposes of s 4(b)(ii), his analysis of the applicant’s work duties and their impact on the applicant’s hands and wrists is consistent with the opinions of Dr Chan and A/Prof Vagholkar. Dr Lai noted that the activities of living a normal life did not involve the same types of repetitive movements as the applicant’s work at the hospital. I therefore find indirect support for a finding that employment was the main contributing factor to an exacerbation of the applicant’s bilateral carpal tunnel syndrome pursuant to s 4(b)(ii) in the report of Dr Lai.
As noted above, a finding that the applicant sustained an injury pursuant to s 4(b)(ii), is not inconsistent with the reports of Dr Masson, which focused only on the onset of the condition.
Considering the lay and medical evidence as a whole, I am satisfied that the nature and conditions of the applicant’s employment as a sterilising technician were the main contributing factor to an exacerbation of the applicant’s bilateral carpal tunnel syndrome for the purposes of s 4(b)(ii) of the 1987 Act.
Section 16 of the 1987 Act provides:
“16 Aggravation etc of diseases—employer liable, date of injury etc
(1) If an injury consists in the aggravation, acceleration, exacerbation or deterioration of a disease—
(a) the injury shall, for the purposes of this Act, be deemed to have happened—
(i) at the time of the worker’s death or incapacity, or
(ii) if death or incapacity has not resulted from the injury—at the time the worker makes a claim for compensation with respect to the injury, and
(b) compensation is payable by the employer who last employed the worker in employment that was a substantial contributing factor to the aggravation, acceleration, exacerbation or deterioration.”
The evidence before me indicates that the applicant has continued to work in suitable duties but has been certified as lacking capacity to perform her pre-injury duties since at least
19 March 2021.
There is, however, in these proceedings, no claim for weekly compensation. The decision in Stone v Stannard Brothers Launch Services Pty Ltd[7], to which the parties both referred in their submissions is authority for the proposition that s 16 of the 1987 Act may fix different deemed dates, depending on the claim. In the absence of a claim for weekly compensation, the date of the claim for compensation is deemed to be the date of injury.
[7] [2004] NSWCA 277.

Having found that the applicant sustained an injury that consists in the exacerbation of a disease, the deeming provisions in s 16 therefore operate so that there is no barrier to the recovery of compensation arising from ss 254 or 261 of the 1998 Act. I am satisfied that notice of the injury was given to the employer as soon as possible after the injury happened and before the worker has voluntarily left the employment in which the worker was at the time of the injury. I am further satisfied that the claim for the compensation was made within 6 months after the injury.
There is no medical dispute between the parties as to whether the surgery proposed by Dr Chan is reasonably necessary. I accept of the medical evidence before me that it is. I am also satisfied that the need for surgery results from the injury. It is uncontroversial that a need for treatment can result from multiple causes. In Murphy v Allity Management Services Pty Ltd[8] Roche DP stated:
“[57] …That is because a condition can have multiple causes (Migge v Wormald Bros Industries Ltd (1973) 47 ALJR 236; Pyrmont Publishing Co Pty Ltd v Peters (1972) 46 WCR 27; Cluff v Dorahy Bros (Wholesale) Pty Ltd (1979) 53 WCR 167; ACQ Pty Ltd v Cook [2009] HCA 28 at [25] and [27]; [2009] HCA 28; 237 CLR 656). The work injury does not have to be the only, or even a substantial, cause of the need for the relevant treatment before the cost of that treatment is recoverable under s 60 of the 1987 Act.
[58] Ms Murphy only has to establish, applying the commonsense test of causation (Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452; 10 NSWCCR 796), that the treatment is reasonably necessary ‘as a result of’ the injury (see Taxis Combined Services (Victoria) Pty Ltd v Schokman [2014] NSWWCCPD 18 at [40]–[55]). That is, she has to establish that the injury materially contributed to the need for the surgery (see the discussion on the test of causation in Sutherland Shire Council v Baltica General Insurance Co Ltd (1996) 12 NSWCCR 716).”
[8] [2015] NSWWCCPD 49.
I am satisfied that the applicant’s current need for surgery is multifactorial. Although the surgery is required due to what appears, on the weight of medical evidence before me to be an idiopathic or constitutional condition, I am satisfied that the work-related exacerbation of that condition has materially contributed to the present need for surgery.
It follows that there will be an order for the respondent to pay the costs of and incidental to the bilateral carpal tunnel release surgeries proposed by Dr Chan.

[2022] NSWPIC 376

13 July 2022