Claridge and Comcare (Compensation)

Claridge and Comcare (Compensation) [2020] AATA 655 (24 March 2020)
Division:GENERAL DIVISION
File Number(s): 2019/0365
Re:Allison Claridge
APPLICANT

AndComcare
RESPONDENT

DECISION
Tribunal:Senior Member P J Clauson AM
Date:24 March 2020
Place:Brisbane

The reviewable decision made on 20 December 2018 is affirmed.
........................................................................
Senior Member P J Clauson AM
CATCHWORDS
WORKERS’ COMPENSATION – Safety, Rehabilitation and Compensation Act 1988 (Cth) – Whether employment contributed to ailment to a significant degree – Balance of probabilities – Risk factor not conclusive of causation – Decision under review affirmed.
LEGISLATION
Safety, Rehabilitation and Compensation Act 1988 (Cth)
CASES
Kennedy Cleaning Services Pty Ltd v Petkraska (2000) 200 CLR 286
Military Rehabilitation and Compensation Commission v May (2016) 257 CLR
SECONDARY MATERIALS
American Medical Association’s Guides to the Evaluation of Disease and Injury Causation, 2^nd Edition
REASONS FOR DECISION
Senior Member P J Clauson AM
24 March 2020
INTRODUCTION

Mrs Allison Claridge, the Applicant, is employed at the Department of Human Services (DHS) on a part-time basis four days a week. She has worked for the DHS since 29 May 2006 and at the date of this hearing was employed as a Compiler APS3 since 19 June 2012.
The Applicant lodged a claim for Workers’ Compensation on 16 July 2018 which stated she was suffering ‘acute tendonitis, causing trigger thumb’.[1] In her claim, she stated that she first noticed her symptoms on 27 November 2017 while she was typing on a keyboard at the time she suffered the injury to her left thumb.
[1] Exhibit 1, T3, pp 33-40.
The medical reports would indicate that the Applicant first consulted her local GP, Dr Kara Griffiths, on 2 March 2018 for treatment of her condition.[2]
[2] Exhibit 1, T5, p 45.
On 2 July 2018, the Applicant was admitted to the Mater Private Hospital and a surgical release of the trigger of her left thumb was performed by Dr Mark Robinson, a Hand and Upper Limb Surgeon.[3]
[3] Exhibit 1, T5, p 50.
On 7 September 2018 the Respondent’s delegate declined the Applicant’s claim[4] based upon the recommendation of the Allianz Care Manager (ACM), who found the condition to be an ailment, but who also found that the condition was not significantly contributed to by the Applicant’s employment.[5]
[4] Exhibit 1, T9, p 88.
[5] Exhibit 1, T8 p 87.
On 27 November 2018, the Applicant sought reconsideration of the determination made on 7 September 2018.
On 20 December 2018, the Delegate of the Respondent affirmed the determination.[6]
[6] Exhibit 1, T14, p 133.
On 21 January 2019, the Applicant applied to this Tribunal for a review of the reconsideration decision dated 20 September 2018.[7]
[7] Exhibit 1, T1, p 28.
THE MEDICAL EVIDENCE
The Tribunal had before it the oral evidence of Dr Blair Christian, Consultant Occupational Physician.
The Tribunal also has the following medical reports which have been considered in making the decision in this matter:
(a)Consultation notes dated 2 March 2018 from Dr Kara Griffiths, General Practitioner[8] noting the referral of the applicant to Dr Mark Robinson for assessment of her thumb condition;
(b)Consultation note dated 9 March 2018 by Dr Griffiths[9] which references the possibility of treatment of the Applicant’s thumb condition by way of a steroid injection into the flexor tendon with medication and rest. Action is noted as requesting an x-ray and a USS guided Cortisone injection;
(c)X-ray and ultrasound report of Dr Alan Kang dated 8 March 2018 noting mild thickening of the thumb flexor tendon sheath at level A1 of pulley in keeping with tenosynovitis and suggesting that an ultrasound-guided steroid injection may be of benefit;[10]
(d)A report of Dr Kang dated 20 March 2018 (Exhibit 1, T5 at 48)[11] confirming that an ultrasound-guided left thumb injection had been conducted by him into the thumb flexor tendon at the A1 pulley level and 0.5ml of Celestone and 0.5ml of 1% Xylocaine. The report indicated no complications and that the treatment was well tolerated;
(e)A report of Dr Robinson dated 20 June 2018 confirming the doctor’s recommendation to surgically conduct a trigger thumb release (Exhibit 1, T5, page 49);[12]
(f)A report of Dr Robinson dated 4 July 2018 confirming the surgical trigger thumb release procedure was conducted on the Applicant’s left thumb on 2 July 2018 at Mater Private Hospital;[13]
(g)The report of Dr Christian dated 30 August 2018;[14]
(h)Supplementary report by Dr Christian dated 18 July 2019 (Exhibit 5).[15]
[8] Exhibit 1, T5, p 45.
[9] Exhibit 1, T5, p 46.
[10] Exhibit 1, T6.2 p 65.
[11] Exhibit 1, T5, p 48.
[12] Exhibit 1, T5, p 49.
[13] Exhibit 1, T5, p 50.
[14] Exhibit 1, T7, p 74.
[15] Exhibit 5.
The Tribunal has also considered other material relating to trigger thumb which the Parties made available to it for the hearing. The Respondent, on 5 April 2019, filed an extract from the American Medical Association’s Guides to the Evaluation of Disease and Injury Causation, 2^nd Edition.[16] The relevant pages of the extract are pages 259 to 262 inclusive. The authors of this work are acknowledged as J. Mark Melhorn, M.D., James B. Talmage, M.D., William E. Ackerman III, M.D., and Mark H. Hyman, M.D.
[16] Exhibit 3.
On 27 January 2019, the Applicant filed material relating to ‘trigger finger’. This material consisted of two articles which appear to have been downloaded from the internet. Neither article has an attributed author’s name attached to it.
Dr Robinson provided an open letter on 10 May 2019[17] which provided a short but incomplete history of the Applicant’s condition and a view as to the causation of the condition. The Tribunal also had the benefit of a statement of Ms Rebecca Latt, the Applicant’s Team Leader, outlining the course of reporting and progressive advice from the Applicant to Ms Latt during the course of her treatment.
[17] Exhibit 7.
THE LEGISLATIVE FRAMEWORK
The legislation governing claims for liability for a claimed condition is the Safety, Rehabilitation and Compensation Act 1988 (Cth) (Act). Section 14 is the appropriate section of the Act which states that the Respondent is liable to pay compensation in accordance with the Act in respect of any injury suffered by an employee if the injury results in death, incapacity for work or impairment.
Section 5A(1) of the Act defines ‘injury’ as:
(a)A disease suffered by an employee; or
(b)An injury (other than a disease) suffered by an employee, that is a physical or mental injury arising out of or in the course of, the employee’s employment; or
(c)An aggravation of a physical or mental injury (other than a disease) suffered by an employee (whether or not that injury arose out of, or in the course of, the employee’s employment), that is an aggravation that arose out of, or in the course of, that employment;
but does not include a disease, injury or aggravation suffered as a result of reasonable administrative action taken in a reasonable manner in respect of the employee’s employment.
Section 5B(1) of the Act defines ‘disease’ as:
(a)An ailment suffered by an employee; or
(b)An aggravation of such an ailment;
that was contributed to, to a significant degree, by the employee’s employment by the Commonwealth or a licensee.
Section 4(1) of the Act states that ‘ailment’ means any physical or mental ailment, disorder, defect or morbid condition (whether of sudden onset or gradual development).
Section 5B(3) of the Act states that ‘significant degree’ means the degree that is substantially more than material.
Section 5B(2) of the Act sets out matters that may be taken into account when determining whether an ailment or aggravation was contributed to, to a significant degree, by an employee’s employment by the Commonwealth or a licensee.
ISSUES
The issue for this Tribunal to decide is whether, on the balance of probabilities, the Applicant’s trigger thumb condition was contributed to, to a significant degree, by the Applicant’s employment with the Commonwealth, thus creating a compensable incapacity in the Applicant.
CONSIDERATION
At the hearing of this matter, the Applicant appeared in person and was self-represented. The Applicant presented before this Tribunal as a bright, well-disposed and credible person, 54 years of age. The Respondent was represented by Mr Jamie Watts, Australian Government Solicitor.
The Respondent acknowledged that the Applicant did suffer a condition and that the condition was an ‘ailment’ as defined under section 4(1) of the Act and that the condition was not an ‘injury (other than a disease)’ for the purpose of section 5(1)(b) of the Act because it was not a sudden and ascertainable or dramatic physiological change or disturbance of the normal physiological state.[18]
[18] Military Rehabilitation and Compensation Commission v May (2016) 257 CLR 468 at 480 and Kennedy Cleaning Services Pty Ltd v Petkraska (2000) 200 CLR 286 at 300.
This is a reasonable concession to make in the opinion of this Tribunal and is not challenged by the Applicant.
The condition and the medical interventions undertaken to treat and alleviate the symptoms of the Applicant’s condition have been well-documented in the medical reports and clinical notes before the Tribunal.
The Applicant contends that her trigger thumb condition was caused by her work which involved repetitive movements associated with keyboard usage. Her work, according to her Team Leader, Ms Latt, in her statement of 20 July 2018, was as a Compiler and:
“… involves collecting screens and ordering docks and scans already collected by the Task Card Author. The main component involved in the role of the Compiler is using the mouse to collect, save, order documents.”[19]
[19] Exhibit 1, T6.3, p 67.
The Respondent contends that the Applicant’s claimed condition was not contributed to, to a significant degree, by the Applicant’s employment with the Commonwealth.
The Applicant, in her written but undated statement[20], which accompanied her Application for Review with this Tribunal dated 22 January 2019,[21] stated that the person conducting the ultrasound procedure on her thumb had explained that she had thickening of the thumb flexor, acute tenosynovitis, which is caused by repetitive use over a long period of time. She further stated that this person asked her what she did for work and she asserted that he suggested that repetitive typing at work for over 12 years was the likely cause. She states that it was this comment that made her connect her trigger thumb issue to a work-related cause. Also the Sonographer had apparently opined to her that the hand grabbing incident with her husband was unlikely to have been the cause of her condition.
[20] Exhibit 1, T3.
[21] Exhibit 1, T1, pp 1 and 2.
The report of Dr Kang, Radiologist, dated 9 March 2018[22] references the clinical details as ‘Pulled thumb seven weeks ago. Avulsion fracture? Tendon injury?'. The findings in the report state:
“X-RAY:
No bony or joint abnormality seen. No soft tissue calcification.
ULTRASOUND:
Mild thickening of the thumb flexor tendon sheath at the level of A1 pulley in keeping with tenosynovitis. Thumb triggering demonstrated in this region during dynamic assessment. Flexor and extensor tendons are intact. No joint effusion, synovitis or ganglion cyst seen.”
[22] Exhibit 1, T6.2, p 65.
Dr Kang’s conclusions were:
“Thumb flexor tenosynovitis.
Ultrasound-guided steroid injection may be of benefit.”
It is noted that the report also mentions that the Sonographer who conducted the ultrasound on the Applicant’s hand was Mr Don Middleton. Presumably, Mr Middleton was the person who was discussing the cause of the Applicant’s thumb condition with her whilst carrying out the procedure which he was trained to conduct. This Tribunal considers that Mr Middleton may have made such comments to the Applicant, however, he was neither a medical practitioner in general practice, nor was he a holder of specialist qualifications in the field of issues affecting the hand. His only expertise, so far as this Tribunal can conclude, is that of a Sonographer. It is also of note that Dr Kang, as a Specialist Radiologist, made no attempt to attribute a cause to the Applicant’s condition in his report.
The Tribunal notes the statement of Ms Latt, the Applicant’s Team Leader, dated 20 July 2018[23] wherein she states at paragraph 6:
“I became aware of the incident when [the Applicant] mentioned it to me in casual conversation (some time in late November 2017). [The Applicant] stated that “She was messing around with her husband, being silly”, when she got her “left thumb caught on something”. [The Applicant] advised that her thumb was still painful, however, she has not consulted a doctor.”
[23] Exhibit 1, T6.3, p 66.
Ms Latt also notes that the Applicant took leave shortly after 6 December 2017 and returned on 2 January 2018. The Applicant advised Ms Latt upon her return that her thumb was not as painful as she had avoided using it, but still had not at this time, sought medical advice.
Ms Latt, in her statement, also noted conversations she held with the applicant on 26 June 2018 during a coaching session, during which the Applicant advised that she had seen Dr Robinson on 19 June 2018 and that he had scheduled her for ‘left thumb release surgery on 2 July 2018’.[24] The Applicant completed an online Injury Report in ‘ESS’ on the same day.
[24] Exhibit 1, T6.3, p 67, para 9.
Ms Latt, on 28 June 2018, also discussed with the Applicant the guided injection procedure she had undergone on 20 March 2018 and which provided only a temporary benefit. Ms Latt’s statement notes that she discussed the costs of the release surgery and that the Applicant said she didn’t have private health cover and that she didn’t mention that she considered this a work-related injury or that she intended to lodge a Comcare claim.[25]
[25] Exhibit 1, T6.3, p 67, para 12.
Ms Latt also states[26] that she queried the Applicant’s ESS online report on 28 June 2018 as she understood that the thumb condition was caused as a result of the incident at home back in November 2017.
[26] Exhibit 1, T6.3, p 67, para 13.
It was during this conversation that the Applicant advised that the ultrasound had identified a thickening which was in line with ‘a repetitive injury’ and would have to be from ‘keyboard work’. Ms Latt notes at this time she had not been given a copy of the ultrasound report from Dr Kang.
The statement of Ms Latt also notes that on 7 March 2018, the Applicant advised her that on 3 March 2018, her GP had referred her for an ultrasound to be conducted on 8 March 2018.[27]
[27] Exhibit 1, T6.3, p 67, para 16.
The clinical note by Dr Griffiths[28] would indicate that she saw the applicant on 2 March 2018 and this is noted by the Tribunal for the purposes of accuracy only.
[28] Exhibit 1, T5, p 45.
Ms Latt also states that the Applicant ‘flexed-off’ to have the guided injection procedure on 20 March 2018 and returned to work for two days following the procedure and then left again for three weeks’ annual leave.[29] It is also noted from Ms Latt’s statement that the Applicant ‘Had not taken any time off for her left thumb injury, nor had she provided any medical information regarding this condition’ prior to her appointment with Dr Robinson for a consultation on 19 June 2018.
[29] Exhibit 1, T6.3, p 68.
The Tribunal accepts the outline as provided by Ms Latt’s statement as a reasonable and accurate recollection of her discussions with the Applicant leading up to her surgical procedure with Dr Robinson on 2 July 2018.
Following the lodgement of a claim with Comcare on 16 July 2018,[30] Allianz Australia Ltd (the Insurer) wrote to Dr Ronald (Blair) Christian, a Specialist Occupational Physician, requesting a comprehensive report on the medical condition suffered by the Applicant.
[30] Exhibit 1, T3, pp 33 to 40.
Dr Christian prepared a report for the Respondent’s insurer dated 30 August 2018.[31] Dr Christian’s report covered the history of the Applicant’s condition and treatment and indicated that he had conducted a physical examination of the Applicant before compiling his report.
[31] Exhibit 1, T7, pp 74 to 81.
Dr Christian considered the Applicant’s occupational history, the history of the subject injury and treatment received for it, the Applicant’s general medical and social history and her general medication for high blood pressure. Dr Christian noted that the Applicant was correctly diagnosed with left trigger thumb and that the condition was caused when ‘The thumb flexor tendons are constricted within the flexor tendon sheath, usually at the level of the A1 pulley. This constriction can be due to thickening of the tendon sheath itself or nodules on the tendon.” The report goes on to say “In [the Applicant’s] case, from the Radiologist’s report on file, the triggering was due to thickening of the tendon sheath.”[32]
[32] Exhibit 1, T7, p 77.
Dr Christian was asked to consider the causation factors for the diagnosis of the condition, including the progression of the condition and the clinical signs and symptoms to support his diagnosis of the Applicant’s condition.
Dr Christian, in his report, drew upon the “AMA Guides to the Evaluation of Disease and Injury Causation”[33], the authors of which he considered to have undertaken ‘a very comprehensive literature review of trigger digit causes and risk factors’ in which they outlined the levels of evidence for various postulated risk factors.
[33] Exhibit 3.
In turning to this review at page 259 of the extract provided, it states:
‘Possible causes of tendon enlargement includes scarring from a partial tendon laceration and idiopathic nodule formation. Less commonly, occupational or avocational activities can cause inflammation and triggering. Blunt trauma is another possible but unusual cause. Many cases of trigger digit are idiopathic (of unknown cause).’
The review also continues with a heading stated “Occupational Risk Factors for Trigger Digits”:
·Combination of risk factors (e.g., force and repetition, force and posture): some evidence;
·Vibration: some evidence;
·Highly repetitive work alone or in combination with other factors: low risk evidence;
·Forceful work: low risk evidence;
·Awkward postures: low risk evidence;
·Keyboard activities: insufficient evidence;
·Cold environment: insufficient evidence;
·Length of employment: insufficient evidence.
At page 260 of the extract of the Guide, it then lists non-occupational risk factors for trigger digits:
·Age: insufficient evidence (some reports of inverse relationship with age);
·BMI: insufficient evidence (obesity increases risk of multiple trigger digits);
·Gender: insufficient evidence (risk increased for females);
·Biopsychosocial factors: insufficient evidence;
·Diabetes: strong evidence;
·Dominant hand: insufficient evidence;
·Smoking: insufficient evidence.
Dr Christian considered this review to be very comprehensive in its terms and indicated that the only strong level of evidence of non-occupational risk factor for trigger digits was for diabetes. He also indicated in his report that there was satisfactory evidence, though not strong evidence for a combination of risk factors, for example force and repetition, force and posture, and also satisfactory evidence, though again not a strong level of evidence, for vibration exposure in the workplace as a cause for trigger digits. However, he indicated that there was only a low level of evidence for increased risk with regard to forceful work, awkward postures and highly repetitive work and there was certainly insufficient evidence for keyboard activities presenting as any risk for developing trigger digits. Dr Christian stated:
“From my reading on this topic, including the AMA review, in my opinion the evidence at this point is sufficient to accept that there are occupational risk factors for trigger digit. The occupational risk factors which in my opinion are sufficiently well established in terms of evidence available, include exposure to vibration, and a combination of risk factors (for example, force and repetition, force and posture). In my opinion, the low level of evidence for highly repetitive work, forceful work and awkward postures, is not at the level where I would be confident in accepting these physical activities as having been shown to lead to an increased risk of trigger digits. Those physical work factors are exceedingly common, and it does seem reasonable to suppose that if there was a direct real and significant increased risk from those physical factors, for causing trigger digits, this would be reflected in the literature as a higher level of risk evidence.”[34]
[34] Exhibit 1, T7, p 78.

Dr Christian felt that it was also unlikely that the Applicant’s left hand trigger thumb was due to the pulling event that occurred with her husband on the Friday in late November 2017 before the onset of symptoms of trigger thumb on the Monday. He felt that the Applicant was clear when he was speaking with her that there was no wrenching or twisting of the thumb and that she had suffered only brief pain and this was felt over the whole hand because she simply pulled her hand free of her husband’s grip. Also, the Applicant was then able to undertake all the usual household activities for the rest of that Friday and over the following weekend without any thumb pain or restriction or tenderness whatsoever. Dr Christian also believes that if the event on the Friday in November 2017 had led to an acute left thumb tendon injury, it would not be plausible that the Applicant would have been pain-free almost instantly following the injury, and pain-free for the rest of the day and the next Saturday and Sunday, before only developing symptoms on the Monday.
Dr Christian also opines that if there had been a tendon injury occurring in that event with her husband on the Friday, on a clinical basis, he would have expected the activity related thumb pain related to tendon injury to have occurred over that Friday and the weekend.
In his report,[35] with regard to the relevant history or pre-existing and/or degenerative or underlying conditions suffered by the applicant, Dr Christian states that:
“There is no identified previous history or identified underlying condition. As noted above, the only condition with strong evidence for being a risk factor for trigger thumb is diabetes, and Ms Claridge does not have a diagnosis of diabetes. As noted above, in my opinion, it is most unlikely that the incident with her husband on the Friday led to an acute thumb tendon injury.”
[35] Exhibit 1, T7, p 79.
Clearly, it would appear that Dr Christian has eliminated the incident with her husband on the Friday and diabetes from the list of causative factors for the Applicant’s condition. It is to be noted that the Applicant seems also to have discounted what we could refer to as the “horseplay” incident as the proximate cause for her trigger thumb.
Dr Christian is of the view, in his original report, that the Applicant’s trigger thumb was due to the thickening of the flexor tendon sheath, the cause of such thickening not being well understood. Dr Christian also indicated that it was likely a number of factors, either in combination or independently, could lead to trigger thumb, other than diabetes, which in the Applicant’s situation had been discounted. He further stated that in most cases the cause of trigger thumb was not able to be clearly identified.
Dr Christian was clearly of the opinion that the evidence of causation in the Applicant’s situation did not support a contention that the Applicant’s work role was a causative factor of the trigger thumb. He then went on to state:
“It follows then logically the trigger thumb was due to other factors, although these are not able to be defined.”[36]
[36] Exhibit 1, T7, p 80.
Dr Christian further considered that the treatment received for the condition was ‘entirely appropriate’ and that there were no restrictions upon the Applicant in conducting her duties at work - ‘She has made a return to full normal work tasks’, and his prognosis was ‘that [the Applicant] will maintain her full recovery from the trigger thumb’.
On 18 July 2019, Dr Christian provided a supplementary report.[37] He was asked to opine in particular on the contents of an open letter provided by the Applicant’s Orthopaedic Surgeon, Dr Robinson, dated 10 May 2019[38] wherein he confirms that she had consulted him on 19 June 2018 and presented with ‘typical features of triggering of her left thumb’. The letter also mentions aspects of employment, the fact she did not play a sport and that she recalled playing around with her husband and that she didn’t recall any specific injury to her thumb directly related to that activity but noticed symptoms some time around that period.
[37] Exhibit 5.
[38] Exhibit 9.
Dr Robinson also stated in the penultimate paragraph of his letter regarding the Applicant’s condition that: ‘Her occupational activities involve typing. Trigger digits are associated with repetitive activity of the digit and on the balance of probability, it could be associated with occupational tasks’.
Dr Christian was requested by the Respondent, as to the words ‘associated with’ in the context of Dr Robinson’s letter, whether they mean ‘caused’. Dr Christian’s view was that Dr Robinson was the appropriate person of whom to ask that question. However, he expanded upon his view of the meaning of ‘associated with’. His interpretation was that those words meant ‘that a level of causation has not been established, but there is a recognised link between symptoms and activity’. He used the example of Carpal Tunnel Syndrome being associated with keyboard work as keyboard work will often lead to increased symptoms of CTS even though there is little evidence that keyboard work itself presents any increased risk of causing CTS. Therefore, the term ‘associated with’ is often used to indicate that a link exists between a certain risk factor or activity, and symptoms without there being any clearly established causative relationship.
Dr Christian also expanded upon the term ‘risk factor’ and its relationship to causation of a condition and what ‘risk’ meant in a medical sense. He explained that the presence of a risk factor did not mean that it caused the condition. He said that diabetes was a risk factor in trigger thumb, but as the Applicant did not have diabetes, it could not therefore have been the cause of her trigger thumb.
Dr Christian further expanded to say that some medical conditions may have many risk factors and that it would be reasonable to expect that not all of those would be present in any individual and that, indeed, for any one afflicted person, none of those firmly established risk factors may be present.
The Tribunal accepts the evidence of Dr Christian that even though there may exist risk factors which may potentially be considered as a measure of likelihood for the potential cause of a condition, it may be the case that even if the person had such a risk factor, for example diabetes, it could not be proven definitively that the identified risk factor was the cause of the condition. It could only be characterised as the most likely cause of the condition. In the case of the Applicant, for example, if she suffered from diabetes and trigger thumb, it could be considered most likely that her trigger thumb was caused by her diabetic condition. However, even so, it could not be proven that diabetes was definitely the cause of the trigger thumb.
In his supplementary report, Dr Christian also provided an explanation of the levels of risk as described in the AMA Guides to the Evaluation of Disease, Injury and Causation, 2^nd Edition as follows:
·Strong - A strong level of evidence indicates at least five high quality scientific studies agreeing that the factor is a risk for that condition, with a relative risk of 2.0;
·Low - The evidence indicates that the relative risk is less than 2.0, that the reasonable medical probability of more than 50% evidence standard is not met, that there is minimal causation (much less than 50% of causation), and that a work-related contribution to the condition is possible but unlikely.
The Tribunal also notes the view outlined in the penultimate and final paragraphs of Dr Christian’s supplementary report that:
“When making reference to scientific evidence-based studies, such as those reviewed within the AMA Guides to the Evaluation of Disease and Injury Causation, it follows that risk factors rated as having a strong level of evidence are provided much greater weight than risk factors identified as having a low level of evidence or insufficient evidence. Again, having a risk factor present does not necessarily mean that the factor in question is the entire or predominant cause of the condition in any one individual’s case. Risk factors are assessed on a population basis. Risk factors help in determining likelihood of causation of a condition, but generally do not enable an assessment of the definitive root cause of a condition in any one individual.
It remains the case for many conditions, that the predominant causative or contributing risk factors cannot be identified with any level of certainty, and the likely cause of condition therefore remains unclear. It is probably safe to say that most conditions have many potential contributing and causative risk factors, and that the underlying cause is often multifactorial.”
CONCLUSION
The Tribunal has considered the history of the Applicant’s condition, the medical evidence from her GP, Radiologist and Surgeon, together with that of Dr Christian and the medical research material he used in guiding his opinion and report.
The Tribunal is satisfied that at the time the Applicant’s condition first manifested itself in November 2017, she may have believed quite reasonably that her condition could have possibly been as a result of a playful moment when her husband had grabbed her by the left hand. There was a moment of some pain over her whole hand, not specifically her thumb, which quickly dissipated. However, by the following Monday, her left thumb became noticeably painful and noted that in moving her thumb from full flexion to full extension and feeling a kind of ‘flicking feeling’ at the thumb IP joint with attendant pain through her whole thumb.
Following her three weeks holiday from work over the Christmas period, she noted that the pain had reduced albeit not completely. After a week or so following her return to work, the pain again increased in frequency. She then consulted her GP who in turn referred her for x-ray and ultrasound examination which diagnosed a mild thickening of the thumb flexor tendon sheath at the A1 pulley level with tendo-synovitis. Ultrasound-guided steroid injection followed this, with limited effect.
The Tribunal noted that the Applicant in her undated statement[39] that prior to the x-ray and ultrasound her condition worsening progressively and became ‘the worst it had been in the entire time’. The Applicant’s statement also indicates that her conversation with the Sonographer, Mr Middleton, at the time he was conducting the x-rays and ultrasound prior to the guided injection procedure indicates that was the point where she began to believe that her condition was caused by some occupational, repetitive use of her thumb, that is, typing. She states ‘This was the first time I actually made the connection to this being a work-related issue’.[40]
[39] Exhibit 1, T1, p 3.
[40] Exhibit 1, T6.2, p 3.
It would appear that the Applicant is referring to Dr Kang’s report when she states ‘He suggested ultrasound-guided steroid injection as treatment; this procedure took place on 22.03.18’. Dr Kang presumably conducted the guided steroid injection,[41] but proffers no opinion as to the cause of the Applicant’s condition in any of his medical notes of either 8 March 2018 or 20 March 2018.
[41] Exhibit 1, T2, p 64.
The Applicant, in support of her assertion that her trigger thumb was caused through occupational events, relied primarily on the conversation with Mr Middleton and the open letter of Dr Robinson of 10 May 2019, together with two unattributed articles downloaded from the internet relating to trigger finger.[42]
[42] Exhibit 8.
It is the view of this Tribunal that Mr Middleton’s comments can bear no evidentiary weight for they are the comments of a Technician who works in a particular discipline but is not, however, a trained medical expert. The commentary is no more than an opinion expressed about the Applicant’s condition based upon what he may have heard experts discussing in relation to other parties’ circumstances generally and applied erroneously to those of the Applicant.
The two internet articles are unattributed and although describing the causes and possible risk factors regarding the condition of trigger finger, go no way towards providing an in-depth counter to the extensive review articles from the AMA Guides to the Evaluation of Disease and Injury Causation, 2^nd Edition[43] as relied upon by Dr Christian. The Tribunal is also persuaded by the comprehensive explanations and interpretations of causation and risk factors both in his reports and in his oral evidence provided by Dr Christian.
[43] Exhibit 8.
Dr Robinson is an Orthopaedic Surgeon whose expertise lies in a different area from that of Dr Christian. The Tribunal accepts that in relation to the rectification of the Applicant’s trigger thumb by a surgical procedure, Dr Robinson has achieved an excellent result for her. Dr Christian also acknowledges this in his report,[44] however, the Tribunal in this matter must be guided by the views of an expert whose field of expertise is focused upon the study and assessment of the causation and effects of disease, injuries and other medical conditions and disorders upon the functional capacity of the patient. It is therefore the opinion of the Tribunal that the views of Dr Christian are to be preferred over those of Dr Robinson in relation to the Applicant’s claim that her trigger thumb was caused as a result of her employment as a Compiler with the Department of Human Services. Therefore, the Tribunal finds, on the balance of probabilities, that the Applicant’s trigger thumb was not caused as a result of her occupation.
[44] Exhibit 1, T7, p 77.
DECISION
The reviewable decision made on 20 December 2018 is affirmed.

I certify that the preceding 74 (seventy-four) paragraphs are a true copy of the reasons for the decision herein of Senior Member P J Clauson AM

..........................................
Associate

Dated: 24 March 2020

Date of hearing: 7 November 2019

Applicant: In Person

Solicitor for the Respondent: Mr Jamie Watts,
Australian Government Solicitor

[2020] AATA 655

24 March 2020

Key Legal Topics

Areas of Law

Employment Law

Statutory Interpretation

Legal Concepts

Causation

Statutory Construction

Appeal

Date of hearing:	7 November 2019
Applicant:	In Person
Solicitor for the Respondent:	Mr Jamie Watts, Australian Government Solicitor