Small and Comcare (Compensation)

Small and Comcare (Compensation) [2017] AATA 2383 (24 November 2017)
Division:GENERAL DIVISION
File Number(s): 2016/2522; 2016/3803; and 2017/3099
Re:Danielle Small
APPLICANT

AndComcare
RESPONDENT

DECISION
Tribunal:Mr S. Webb, Member
Date:24 November 2017
Place:Canberra

The reconsideration decision in application 2016/2522 is set aside. This means the determinations revoked by that decision are reinstated. The matter is remitted to Comcare to determine Ms Small’s compensation entitlements under s 16 and s 19 of the Safety, Rehabilitation and Compensation Act 1988.
The reconsideration decision in application 2016/3803 is affirmed.
The reconsideration decision in application 2017/3099 is affirmed.
The parties have 7 days in which to make submissions in respect of costs. If no submissions are received, Comcare will be ordered to pay Ms Small's costs in application 2016/2522 as agreed or taxed.
........................................................................
Mr S. Webb, Member
COMPENSATION – accepted low back and other injuries – soft tissue injury – X-ray not sufficient to reveal precise nature of injury – clinical judgement – divergent expert opinions – episodic flaring of symptoms – continuation of injury – incident occasioning increased symptoms consistent with pathological change – new injury claim rejected – meaning of ‘aggravation’ – no jurisdiction to determine liability for ‘aggravation’ under new injury claim – original injury continuing as an operative and effective cause of incapacity – revocation of multiple compensation determinations over a long period – revocation set aside – incident in the course of a compensation meeting held in Applicant’s work place – fresh injury claim – frank injuries arising out of or in the course of the employment – inconclusive evidence low back and lower limb symptoms arise from pathological change – symptoms attributable to pre-existing low back condition – continuing effect of frank injuries not established – related decisions affirmed
Safety, Rehabilitation and Compensation Act 1988, s 4, 5A, 5B, 6, 16, 19, 67
Australian Telecommunications Commission v Tzikas (1985) 5 AAR 173
Comcare v Martin [2016] HCA 43
Commonwealth of Australia v (K C) Smith (1989) 18 ALD 224
Jones v Dunkel (1959) 101 CLR 298
Kirkpatrick v Commonwealth (1985) 9 FCR 36
Military Rehabilitation and Compensation Commission v May [2016] HCA 19
Neat Holdings Pty. Limited V. Karajan Holdings Pty. Limited and Ors (1992) 110 ALR 449
Re Day (2017) 340 ALR 368
Repatriation Commission v Smith (1987) 74 ALR 537
REASONS FOR DECISION
Mr S. Webb, Member
24 November 2017

Danielle Small loved to ride horses. After leaving school she had opportunity to ride horses in her employment by the Australian Federal Police. In a training exercise, she twice fell from a horse in the course of her employment. She sustained injuries to her lower back and other parts of her body. She claimed and was paid compensation. Her symptoms settled but she has been plagued with low back pain which has followed a variable and episodic course, flaring from time to time. The cause of this pain is a matter of dispute.
Some time after the original injury, Ms Small fell down some stairs in her home and again claimed compensation. This claim was rejected by primary determination and on reconsideration, but compensation payments continued under the initial claim as Comcare’s liability continued. Years passed. Comcare reviewed her case and decided that her low back injury had resolved some years previously and a large number of compensation determinations should be revoked. A meeting was arranged to discuss this and other matters with Ms Small. In the course of that meeting Ms Small fainted and fell to the floor, sustaining a number of injuries. She made a further claim for payment of compensation. This was accepted in part, but claims relating to her lower back were rejected. The rejection was then reconsidered and affirmed. Subsequently, Comcare determined that the injuries sustained in that fall resolved and Ms Small had no present entitlement to compensation. This decision was reconsidered and affirmed.
From all this, Ms Small lodged three applications for review of Comcare’s reconsideration decisions, including the revocation decision.
The applications came on for hearing. There were some procedural issues.
Procedural issues relating to the hearing
As I understand it, the proceedings in the Tribunal progressed unremarkably and in the usual way. Over more than 18 months, the parties engaged in a number of conferences and a great deal of material was produced. Each party filed and served a Statement of Facts, Issues and Contentions, setting out their respective cases. Finally, the applications came on for hearing.
On that background, it is surprising and troubling that Comcare advised at the outset of the hearing, without notice, that new issues would be pressed. It is surprising because Comcare was legally represented by McInnes Wilson Lawyers throughout the proceedings, and one would expect all relevant issues would have been considered and points of disputation would have been clearly identified well ahead of the scheduled hearing. Apparently, this did not occur and additional issues were identified shortly before the hearing. It is troubling because conduct of this kind gives rise to serious issues of procedural fairness, which the Tribunal is bound to deliver to both parties. With all the resources Comcare has at its disposal, one would expect better in a case of this kind.
Nonetheless, in the circumstances, the issues of procedural fairness were able to be dealt with in a satisfactory manner, and Ms Small’s legal representatives agreed that the hearing could proceed without delay.
I should say at this point, when dealing with preliminary and procedural matters, Ms Small did not provide a detailed statement ahead of the hearing, setting out her account of the injuries subject of these applications and the circumstances in which they occurred, as well as an account of symptoms and related matters of present relevance. Of course, without being directed to do so by the Tribunal, that was a matter for her. Nonetheless, it would have been helpful had she done so.
There are two further matters concerning the preparation of this case for hearing and the calling of witnesses about which I will say something now in general terms – I will deal with the specific issues in due course.
As the documents plainly reveal, many medical practitioners have examined or treated Ms Small since her initial injury on 24 March 2009. She has been treated by general practitioners whose clinical notes have been produced. She has been treated in hospitals, and the hospital notes have been produced. She has consulted surgeons to discuss treatment options, and some of the resulting reports are before the Tribunal.
Where the content of clinical notes of a treating doctor is controversial, and questions about the completeness or accuracy of the information recorded arise, one might expect the doctor to be called upon to explicate the notes. This is particularly so in the case of a treating general practitioner, where the content of the doctor’s clinical notes do not sit comfortably with a subsequent report. But, as will appear, despite a controversy about the content of clinical notes and a report by Dr Tang, Ms Small’s previous treating general practitioner, this did not occur.
Similarly, as the precise nature of Ms Small’s lumbar spine condition is in dispute, and the controversy relates, at least in part, to neurological issues in the lumbar spine, one might expect that the neurosurgeon who examined her on two occasions in a treatment context might be called upon to illuminate her spinal condition and the aetiology of her related symptoms. But this, too, did not occur.
On several occasions, Ms Small has been examined by orthopaedic surgeons and occupational physicians in a medico-legal context. All but one of these expert doctors were briefed by Comcare or her employer and produced reports that may support her case. The one exception is the specialist doctor most recently briefed by Comcare, on which it relies in preference over previous medico-legal expert reports. Comcare declined to call previous medico-legal experts from whom it and the AFP had obtained reports. Comcare asserts that only the most recently briefed expert had access to all relevant materials.
Where expert reports have been provided to the Tribunal, it is for either party to decide if the expert is required to give oral evidence. Where Comcare chooses not to rely upon an expert opinion it (or an employer) has obtained, and it refuses to call the expert to give oral evidence, a claimant may urge the Tribunal to draw adverse inferences. I do not propose to delve into the controversy over applicability of the principle drawn from Jones v Dunkel[1] in non-adversarial Tribunal proceedings, such as this. That aside, it is open for the claimant to call the expert to give evidence, whereupon the claimant would bear the cost (subject to any subsequent orders) and the expert would be cross-examined by Comcare. Procedural difficulties relating to such matters could be avoided if, in order to assist the Tribunal to reach the correct or preferable decision, Comcare was to call the expert. Whether or not that is done, in any event, if the expert’s report forms part of the materials before the Tribunal, the Tribunal must properly assess it.
[1] (1959) 101 CLR 298, per Kitto J at [5]; see discussion in Howes v Comcare [2016] FCA 1521 at [67] to [69].
Finally on procedural matters, a dispute arose shortly before the hearing in respect of a proposal for two expert witnesses to give their evidence concurrently. It was not possible to resolve this dispute and to take oral evidence from the experts concurrently in the usual manner for want of time. With the agreement of the parties, a revised procedure was implemented. At my request, the experts engaged in a private conference to discuss relevant issues prior to giving their oral evidence separately. For this purpose, the Tribunal provided each expert (one in Canberra at the Tribunal premises and the other in Sydney) with a brief summary of Ms Small’s oral evidence and a number of questions. Each expert noted their agreement or disagreement in response to each question, and the notes were taken into evidence.[2] The need for such an unusual procedure could have been avoided if the arrangement for concurrent evidence had been made well ahead of the hearing.
[2] Exhibits 4 and 8.
Factual background
Ms Small has ridden horses since childhood.
In July 2008, Ms Small underwent a medical assessment and detailed physical examination in her employment. This was conducted by Dr Low and Dr Sweeney. There is no suggestion that she had any spinal issues or symptoms in her low back at that time.[3]
[3] Exhibit 13, pages 8 and 16.
On 24 March 2009, Ms Small engaged in a training exercise in which she was riding a large horse (it was 16 hands at the withers). The exercise involved negotiating a 400mm jump at a canter. The first time she did so, she was raised in the three-point position when the horse went over the jump. On landing, it bucked, throwing its head up and throwing Ms Small off. She fell to the ground, but was not hurt and quickly remounted to try the jump a second time. Once again, she came round at a canter and negotiated the jump with the horse. Once again, the horse bucked on landing. But this time the horse’s head hit Ms Small in the jaw. She pushed herself off to the left as the horse bucked and recalls seeing the horse’s legs as she fell, but then nothing for a time. When she came to, she experienced nausea and pain in various parts of her body. Her supervisor witnessed the incident and completed an incident report.[4]
[4] T4.
Ms Small’s evidence is that when she came to, she immediately felt sharp pain in her head, neck, right arm and shoulder, lower back and in both legs to the feet. There is a controversy over whether she experienced bilateral lower limb pain at that time.
She attended the Emergency Department of the Canberra Hospital, but the hospital notes do not record any complaint of bilateral leg pain.[5] I note, however, there are notes of lower limb “weakness” over subsequent days.[6] Spinal investigations were undertaken, including X-rays of her lumbar spine. These showed a Grade 1 lytic spondylolisthesis at the L5/S1 level with pars defects.[7] There is no dispute this abnormality was in existence, albeit asymptomatic, prior to Ms Small falling from the horse. There is a dispute about whether the spondylolisthesis itself, or its effect on the L5/S1 or L4/L5 discs, was rendered symptomatic by the fall. This is a matter to which I will return.
[5] Exhibit 15, pages 1-11.
[6] Ibid, pages 13 and 15.
[7] T5 folio 19.
Ms Small maintains that she experienced centrally located low back pain and bilateral leg pain thereafter in varying degrees. This is controversial. Her evidence is that she had no prior history of low back and leg pain before falling from the horse on 24 March 2009, but from that day forward to the present she has experienced low back symptoms. She explained that, while the intensity of pain has varied, the location of the pain has not changed – it was (and still is) centrally located in the mid to lower level of her lumbar spine and across her lower back: she pointed to a level lower than the top level of her hips and above the base of her back. Her evidence is that the pain fluctuated from insignificant to severe, where she was severely restricted by pain and unable to work. She agreed that there were periods when she was not troubled by pain or she had no pain, but maintained that it returned and flared without provocation or following minor activities, such as reaching down to pick up a light drink bottle from her car, or sitting for long periods at work.
Ms Small said that she would only seek medical treatment for her low back and leg pain symptoms when they flared to the extent she required stronger analgesic medications than she could buy over-the-counter. In Ms Small’s submission, the absence of express reference to low back pain in the clinical notes of her treating doctors after 7 October 2009 to 25 September 2010[8] may reflect this practice, although she asserts that the doctor may simply not have recorded all that was said in each consultation. I note that Ms Small did not claim compensation after 7 October 2009 until 24 September 2010, and there are no medical certificates of injury-related incapacity during the intervening period.[9] Dr Tang, Ms Small’s treating general practitioner at the time, reported “Her pain did not bother her much from September 2009 to 25 September 2010”.[10]
[8] Exhibit 15, pages 310-312.
[9] See T74 folios 309-310.
[10] T17 folio 73.
Ms Small underwent rehabilitation and treatment, including physiotherapy and managed exercise, with good effect.[11] On 3 August 2009, she returned to full duties at work and she attempted to resume recreational activities of a physical nature, including horse riding, bush walking and sports of different kinds. Ms Small’s evidence is that she persisted with these activities as much as she could, but her low back symptoms restricted what she could do.
[11] See T14 folio 66 and T15, for example.
On 3 August 2010, Ms Small indicated that she had back pain in the emBODYment Pre Exercise Questionnaire.[12] She explained that she underwent physical training and exercise with emBODYment[13] and a personal trainer. This, she asserts, was for therapeutic purposes, as well as in pursuit of her career aspiration to pass the fitness test necessary to become a sworn officer of the Australian Federal Police. But her low back symptoms persisted and these prevented her from achieving that goal.
[12] Exhibit 15, page 27.
[13] Ibid, pages 26-33.
Ms Small was closely examined about incidents in the period from 24 September 2010 to 18 May 2011. She explained that on 24 September 2010 she experienced a ‘click’ in her lumbar spine when descending some stairs in her home which was immediately followed by intense low back pain and pain radiating into both legs down to her feet – the pain was in the same location as she had previously experienced after the 24 March 2009 injury. This description is consistent with the clinical notes of the Calvary Hospital Emergency Department,[14] where she sought treatment. The Hospital notes record –
“PMH – CHRONIC BACK PAIN FROM BACK INJURY
Has been having a niggling lower back pain for the last 10 days, which became worse today.”[15]
[14] T77 folios 515-516.
[15] Ibid, folio 516.
Ms Small agreed that this incident occurred after a period of weeks in which she had been undertaking exercise to lose weight – she reported as much to Dr Tang.[16]
[16] Exhibit 15, page 312; T17 folio 73 refers.
Ms Small agreed that she hurt her lower back when horse riding on 11 October 2010. At that time she was engaging in horse riding and walking activities for approximately one hour three times each week.[17] Her evidence is that, as much as she loved horse riding and wanted to continue with it, she found this difficult because of her low back symptoms.
[17] Ibid, pages 29 and 312-313.
On 14 October 2010, she fell and broke a tooth but did not expressly refer to back symptoms when seeking treatment,[18] although she maintains that her low back was still a problem at that time.
[18] T77 folio 513..
The clinical notes of the Gungahlin Injury Rehabilitation Centre reveal that Ms Small presented on 9 March 2011 with a “lower back sprain”.[19] The clinical notes record –
[19] Exhibit 15, pages 391-392.
“lower back pain since 2009
falling 2009 from a police horse
was in hospital TCH
ixed with mri? ct scan
was advised re ? spondylolisthesis
has been having physion
was advised by physio to see chiro for abnormal pelvic tilt
lower back pain aggravated since then
no neurological symptoms of lower limb
Examination:
tender over l/s spine and para lumber muscles
II nad
Reason for contact:
lower back sprain
aggravation of old injury”[20]
[20] Exhibit 15, page 392.
Ms Small agreed that she returned to this Centre on Monday 4 April 2011. The clinical notes record –
“Injured lower back 2 years ago falling off horse. Has had a flare of back pain since last night. Increased exercise over the weekend, but no injury.
Low back pain radiating down back of both legs. No leg weakness. Ok at rest, worse with movement.
o/e – Tender over SI joints bilat and L4-5 region. Reduced ROM due to pain
Imp – Acute on chronic back pain”[21]
[21] Ibid, page 391.
Ms Small attended this practice again at 3:02 pm on 18 May 2011, in respect of which the notes record “niggles couple of day lumbar injury 2008 sitting 12 [hours]…”.[22]
[22] Ibid.
Ms Small gave evidence of an incident on the evening of 18 May 2011 that caused her to attend the Calvary Hospital Emergency Department.[23] By her account she returned home after a physical training session and experienced a ‘click’ in her lumbar spine when ascending stairs in her home. She immediately experienced severe low back and shooting bilateral leg pain, her legs gave way causing her to fall down three stairs and land on her lower back.[24]
[23] Exhibit 15, pages 45-48; clinical notes on pages 313 and 393 refer.
[24] T23 folio 98 refers.
There is some controversy about the sequence of events in this incident. Ms Small says she experienced a “back spasm that caused my legs to give way” but the Calvary Hospital clinical notes record –
“…
LBP since 2009 from fall from horse
21yo ♀ fell down 4 steps ~ 2030
-    felt a click in LB
-    landed on lower back+ hit occiput but no lOC
-    able to get up but immediate shooting pain down backs of legs
-    ongoing bilateral sciatica
…”[25]
and
“slipped and fell down 4 steps tonight at 2030hr; able to get up, but felt a ‘click’ in her lumbar back and had immediate onset of severe bilateral ‘sciatica’ distribution pain down to level of ankles
no weakness in legs…
longstanding history of LBP, and has worked hard on maintaining good core strength”[26]
[25] T77 folio 507.
[26] Ibid folio 508.

As will appear, I accept Ms Small’s account of the sequence of events.
Ms Small’s evidence is that the severity of her low back and leg symptoms was much worse after this incident – she described this in comparative terms: pain she had experienced previously and considered to be 8 out of 10 would only be 4 out of 10 when compared with the new pain.
Ms Small lodged a compensation claim in respect of the 18 May 2011 incident.[27] Comcare rejected the claim on grounds that the claimed injury did not arise out of or in the course of her employment.[28] Ms Small requested reconsideration. Comcare affirmed the determination rejecting the claim and concluded that “the event on 18 May 2011 was a flare-up of your back condition rather than a new injury”.[29]
[27] T22.
[28] T28 folio 121.
[29] T34 folio 150.
Ms Small did not seek further review of this decision, and the decision is not presently before the Tribunal.
Ms Small continued to claim and was paid compensation in the period from 18 May 2011 to 18 May 2016.[30]
[30] T81 folios 581-605.
Ms Small explained that after 18 May 2011 her low back pain was relentless and she subsequently obtained various specialist opinions and treatments, including from Professor Cohen,[31] Professor Cousins[32] and Dr Speldewinde,[33] pain specialists, and from Dr Salmon,[34] Dr Maloney[35] and Dr Pik,[36] neurosurgeons. By her account, she obtained some relief once a spinal stimulator was inserted, but the symptoms returned when the implanted leads of this device detached, necessitating further surgery to reattach them. Despite this device, on her evidence, she continued to experience low back and lower limb symptoms thereafter, to the present.
[31] Exhibit 14.
[32] T56 and BT9.
[33] T36, T41, T45, T46 and T49.
[34] T24 folio 99 refers.
[35] T57 folio 231 refers.
[36] T50, T55 and T57.
The 14 June 2011 MRI of Ms Small’s lumbrosacral spine contains the following report –
“FINDINGS: …
At L4/5, there is a mild disc degeneration and minimal reduction in disc height and superimposed on this, there is a central to bilateral para-central contained central disc protrusion AP diameter of up to 4mm superimposed on degenerative disc end plate spurring. There is a mild bilateral lateral recess stenosis due to the disc protrusion but no neural compression.
At L5/S1, there is a mild Grade 1 anterior listhesis of L5 on S1 by around 2-3mm with subluxation of the facet joints. There is hypoplasia of the posterior L5 arch particularly on the left that may predispose to altered mechanical stress. A very small disc protrusion at the L5/S1 foramen may result in left L5 symptoms.
No canal stenosis.
CONCLUSION:
1. Non-compressive L4/5 disc protrusion that may be correlated for axial low back pain.
2. L5 posterior arch – normal variant with subluxed L5/S1 facet joints and mild L5 anterior listhesis on S1.”[37]
[37] T20 folio 78.
When this evidence is compared with the report of the 24 March 2009 X-ray, two important differences can be noted. Firstly, the MRI reveals some reduction in height of the L4/L5 disc and a non-compressive disc protrusion with mild bilateral recess stenosis which was not apparent on the X-ray. Secondly, the MRI reports 2-3mm of anterior listhesis (forward slippage) of L5 on S1 and very small disc protrusion at the L5/S1 level that was not apparent in the X-ray.
On 12 April 2012, Dr Cairns, a consultant orthopaedic surgeon, examined Ms Small and provided a medico-legal report to Comcare, in which he reported –
“Diagnoses:
(I)Chronic mechanical low back pain.
(II)L4/5lumbar intervertebral disc degeneration/protrusion.
(III)Developmental grade 1 spondylolytic spondylolisthesis.
The underlying anomalies demonstrated on imaging investigations are developmental in origin. The aetiology of the mechanical low back pain derives from provocation and aggravation sustained in the work-related incident of 24 March 2009…
Ms Small’s condition has not yet resolved.”[38]
[38] T38 folio 168.
Dr Cairns was not called to give oral evidence.
On 12 July 2012, Dr McBurnie, a consultant occupational physician, examined Ms Small and provided a medico-legal report to Comcare, in which she said –
“Ms Small initially injured her lower back in March 2009 in a fall from a horse. She had episodic lower back pain after that injury until May 2011, when she had a severe spasm going up a flight of stairs that resulted in her falling down the stairs.
She has had constant severe pain since…”[39]
[39] T42 folio 187-188.
Dr McBurnie was not called to give oral evidence.
On 25 March 2013, Dr Pik reported –
“[Ms Small] is a 26 year old lady who has had an episode of low back pain in 2009 which lasted for 6-8 months. This episode then gradually resolved over time.
In 2011 [Ms Small] experience [sic] another episode of low back pain. Unfortunately this low back pain has persisted for the past 2 years.
The patient’s low back pain is concentrated in the lower lumbar area. There is occasional radiation of pain down both legs with the left leg affected more than the right…
…
The patient’s symptoms are worse with forward bending, physical exertion and stress. The symptoms can be improved partially by lying on her back with her hips and knees flexed.
…
I reviewed the patient’s old MRI scan from 2011. This scan showed evidence of dessication of the L4/5 intervertebral disc associated with decreased disc height and a minor non compressive disc bulge. At L5/S1, there was evidence of a Grade 1 spondylolisthesis, possibly due to bilateral L5 pars defects…
…
It is my impression that [Ms Small] has clinical features of mechanical low back pain due to a combination of discogenci pain as well as pain possibly arising from L5 pars defects.”[40]
[40] T50 folios 219-220.
Further investigations were undertaken and Dr Pik reported on 13 May 2013 –
“The lumbar discogram showed reproduction of the patient’s usual back pain on injection of the L4/5 disc. Injection of the L5/S1 disc caused a minor degree of pain…
… Essentially, the patient has discogram proven discogenic low back pain arising from the L4/5 disc.”[41]
[41] T55 folio 227.
On 9 June 2015, Dr Wilkins, a consultant occupational physician, examined Ms Small and provided a medico-legal report to Comcare, in which he said –
“Ms Small’s principal area of pain is at L4/5 and L5/S1… At L4/5 there is a disc bulge, and at L5/S1 there is an anterolisthesis.
Disc bulges in the lumbar spine involve protrusion of the “shock absorber” material which normally separates the bony spinal elements. These can occur spontaneously, but are more common after trauma such as strains or falls (as is apparent in the case of Ms Small) Disc protrusions may or may not be accompanied by sciatic pain radiation. In the past this was a prominent feature of Ms Small’s condition.
Spondylolisthesis is a forward “slippage” between vertebrae. Many causes have been hypothesised, but there is no single identified cause. The accompanying anatomical abnormality may result in increased tension on exiting nerve roots, with resulting radicular pain in the buttocks or lower limbs, as has been the case for Ms Small in the past.
…
Prior to Ms Small’s injury sustained on 24 March 2009 she was completely asymptomatic. In my opinion, her current conditions result from those falls and also that she later experienced at home in 2012…”[42]
[42] T65 folios 256-257.
On or about 13 July 2015, Comcare assigned a new case officer to Ms Small’s case – Ms Provins.[43] A review was conducted. In or about November 2015, Ms Provins came to the view that Ms Small’s March 2009 injury had resolved prior to 25 September 2010 and related compensation determined from 18 May 2011 should be revoked.[44]
[43] Exhibit 11 page 1.
[44] Exhibit 11, page 3.
On 4 February 2016, Ms Provins requested a meeting with Ms Small and Chi Chu, her Australian Federal Police rehabilitation case manager.[45] The meeting was scheduled to occur at 9.30am on 9 February 2016.[46] Ms Small was asked to attend the meeting by Ms Chu.[47] A brief agenda was circulated shortly before the meeting –
“Topics to be discussed
-    Liability Management
-    Complaint Management
-    Rehabilitation Management”[48]
[45] AT 21 folio 72
[46] Ibid folio 71.
[47] AT21 folio 65; Exhibit 10, page 1.
[48] AT21 folio 77; Exhibit 11, Annexure E.
The meeting took place at the Winchester Police Station, where Ms Small worked. She attended with her father and Ms Chu. Two Comcare officers, Ms McLeod and Ms Provins, attended by telephone. Detailed statements of Ms McLeod, Ms Provins and Ms Chu are before the Tribunal and each was called to give oral evidence.
In the course of the hearing, Comcare conceded that the exclusionary provision in s 5A(1) of the Safety, Rehabilitation and Compensation Act 1988 (the SRC Act), pressed at the outset of the hearing, is not enlivened in the circumstances. I accept that concession is well made and, for this reason, it is not necessary to set out detailed facts that go to questions of reasonableness.
Ms Small’s evidence is that she started to feel breathless and unwell shortly after the meeting commenced and Ms Provins commenced explaining the review findings. It appears that Ms Small stood up, but before long collapsed in a faint and fell to the floor, hitting her head on a door as she fell.[49]
[49] AT21 folio 61 and Exhibit 10, page 2 refer.
Ms Chu reported the incident and an Incident Details – Supervisor report was completed. This document sets out details of the incident and Ms Small’s employment at the time –
“Type of Employment:  Permanent Full time
Type of Employee:  Support
Duty Status:  Working at usual workplace
Overtime or outside normal working hours:   No
…
Injury or illness sustained:  Fainted, hit head, possible hurt back
Body part most affected:  head and back
…”[50]
[50] AT12 folio 38.
Ms Small’s evidence is that, when she came to a short while later, she was on the floor with pain in various parts of her body, including in her head, neck, left shoulder, low back and legs. Her father raised her legs and soon she was able to rise from the floor. The meeting had come to an end and Ms Chu had left the room. She and her father went and spoke with her supervisor and then she went home. Soon afterwards she attended the Calvary Hospital.
The Calvary Hospital notes confirm that Ms Small attended the Emergency Department, complaining of -
“1.       Central Neck Pain & L side to L shoulder
2.        L Shoulder Pain
3.        L Hip & Pelvis- Pain Laterally
4.        Shooting pain into legs bilaterally.
…
Shooting pain bilaterally to legs similar to previous neuro pain.”[51]
[51] BT6 folios 16-17.
X-rays of her cervical and lumbar spine were taken. The resulting reports did not identify any acute injury.[52]
[52] Ibid folio 19
Subsequently, the clinical notes record –
“[Ms Small] states some dull feeling in both thigh
..
Both thighs both anteriorly & posteriorly dull on P5 & prick examination
Dose [sic] not follow a dermatonal distribution.
…
LBP & referral into upper thighs down to knees”[53]
[53] BT6 folios 21, 22 and 25.
Ms Small lodged a compensation claim in respect of these ailments.[54] Comcare accepted liability for the injuries to her head, neck, shoulder and hip, but rejected her claims in respect of a low back and femoral nerve injury.[55] These decisions were affirmed on reconsideration.[56] Ms Small lodged an application for review of this decision by the Tribunal – application 2016/3803.[57]
[54] AT15 folio 44.
[55] AT27 and AT35.
[56] AT41.
[57] AT2.
Her evidence is that the numbness in her right leg subsequently resolved, but she still experiences numbness in the thigh of her left leg.
On 9 February 2016, after the meeting with Ms Small, Comcare notified her of its intention to “undertake a reconsideration of own motion in relation to Comcare’s acceptance of compensation after 18 May 2011”.[58]
[58] T67 folio 264.
On 12 April 2016, Dr Le Leu, a consultant occupational physician, provided a medico-legal report to Comcare. The doctor was briefed with more than 754 pages of documents. The doctor reported his examination findings, including loss of range of motion in Ms Small’s neck, left shoulder and lumbar spine, and that “She has lost sensation over the front of both thighs; this was to sharp, light and blunt touch”.[59] Dr Le Leu reported the following diagnoses –
“Cervical spine: she has suffered a whiplash-type injury to this area which may be WAD III. I note she had a “musculoskeletal injury to the neck and right arm” in March 2009, but this seems to have settled.
Left shoulder: she may have suffered a rotator cuff injury. I could not elicit signs of impingement on this occasion.
Lumbar spine: possible temporary exacerbation of pre-existing injuries without any disturbance of spinal cord stimulator.
Thigh sensory disturbance – symmetrical – involving the distribution of the anterior femoral cutaneous nerve.
Left knee: lateral compartment injury.”[60]
[59] AT32 folios 195-196.
[60] AT 32 folios 196-197.
Dr Le Leu was closely examined on the persistence of ‘whiplash-type’ injuries and the cause of Ms Small’s sensory thigh symptoms. His evidence is that, in some cases, symptoms of whiplash-type injuries may persist for more than two years and that Ms Small’s sensory thigh symptoms may have a neurological basis. These opinions are controversial.
On 15 April 2016, Comcare issued a reconsideration decision of its own motion, stating –
“In my view, the evidence indicates that your back injury in 2009 was minor, and that it gave you few, if any, problems by about October 2009. As diagnosed by Dr Tang, your back injury was merely a soft tissue injury. The evidence of your subsequent pain and time off work … does not point to any lasting structural injury to your lower back resulting from your fall on 24 March 2009.
Consequently, I have decided that the determinations made from 18 May 2011 to pay for your medical and other treatment and incapacity benefits under sections 16 and 19 of the SRC Act from 25 September 2010, are no longer correct and they have been revoked.”[61]
[61] T69 folio 281-282
Ms Small applied for review of this decision by the Tribunal – application 2016/2522.
On 15 September 2016, three specialist doctors provided reports to the Australian Federal Police through Ms Chu: Dr Stokes, a consultant orthopaedic surgeon; Dr Low, a consultant occupational physician; and Dr Oelrichs, a consultant psychiatrist. These doctors were not called to give medical evidence, so relevant aspects of their reports could not be further examined or tested.
Dr Stokes reported –
“[Ms Small] is a 29-year-old lady who presents with the symptoms and signs of mechanical back pain secondary to intervertebral disc protrusion at the L4/5 level and an aggravation of an underlying developmental anomaly at L5/S1 where Ms Small has bilateral pars defects and a forward slip of L5 on S1 of grade 1 severity.
On the balance of probability, the damage of a disc in such a young person requires a significant traumatic event and the two falls from her horse in 2009 would provide that significant trauma.
In 2011 she suffered a significant aggravation of the injury to the L4/5 disc probably resulting in the protrusion of the disc reactivating her low back pain…
In February [2016], following a vasovagal attack, Ms Small sustained muscular soft tissue strains to her shoulder, neck, thigh and an aggravation of her lower back symptoms…”[62]
[62] BT11 folio 101.
In Dr Stokes’ opinion, the muscular strains to Ms Small’s neck and shoulder could be expected to resolve within weeks, but his prognosis in respect of her low back condition was guarded.
Dr Low reported –
“In terms of her physical condition, the specific diagnoses we found were that of L4/5 intervertebral disc protrusion, L5/S1 spondylolisthesis of grade 1 severity. She also had evidence of resolving muscular strains to her neck and shoulder.
…
It is reasonable that her L4/5 disc protrusions are related to the falls as described in the body of the report, that being falling off a horse during training and later falling down the stairs. It cannot be excluded that she had pre-existing spondylolisthesis.
The origin of the muscular strains are wholly related to the described fall second to vasovagal episode.
…
We consider that her muscular strains are resolving.
With respect to her lower back we consider her symptoms as currently stable, however we note that given the underlying pathology persists, may deteriorate in the foreseeable future.”[63]
[63] BT12 folio 115.
For present purposes, as there is no suggestion of malingering or psychiatric causation of the physical conditions to which the reviewable decisions relate, it is not necessary to consider the report of Dr Oelrichs (or an earlier report by Dr Hundertmark, another consultant psychiatrist).
On 20 September 2016, Dr Mourad, a consultant orthopaedic surgeon, provided a medico-legal report to Comcare.[64] The doctor was briefed with a large number of documents relating to Ms Small’s relevant medical and claim history from March 2009. The doctor reported –
[64] Exhibit 5.
“Ms Small … sustained a fall of [sic] a horse in March 2009. As a result of that fall, she developed back pain of six months’ duration which subsequently resolved. Imaging at that time revealed no evidence of an acute injury but there was evidence of pre-existing L5/S1 anterolisthesis. Ms Small then redeveloped back pain in May 2011…
…
Following her fall on 2009 all her symptoms resolved.
…
Yes, I believe that Ms Small’s compensable lumbar condition ceased in October 2009.
…
I believe that Ms Small’s flare-ups in September 2010, October 2010, April 2011 and May 2011 were not as a result of the fall on March 24^th 2009 but rather her pre-existing lytic spondylolisthesis of L5/S1.
…
In my opinion, the main factor which has contributed to Ms Small’s claimed lumbar spine aggravation and thigh numbness is the natural progression of her L5/S1 spondylolisthesis…
…
L5/S1 spondylolisthesis can often lead to degenerative disc disease.”[65]
[65] Exhibit 5, pages 12-15.
Dr Mourad provided two supplementary reports to Comcare dated 7 November 2016[66] and 13 July 2017.[67] The doctor also gave extensive oral evidence to which I will return. He disagreed with Dr Le Leu’s opinions about the existence of a whiplash-type injury as a result of Ms Small’s vasovagal event on 9 February 2016 and the cause of her sensory thigh symptoms.
[66] Exhibit 6.
[67] Exhibit 7.
On 28 November 2016, Dr Martin, Ms Small’s then treating general practitioner reported –
“Generally [Ms Small’s] contusions had settled by early March and required no further management was required. By April I did not feel Ms Small required further investigation into her shoulder strain as it had shown significant improvement. Come May her neck and shoulders, with associated headache had improved. During the period from 9 February 2016-23 June 2016 Ms Small experienced ongoing low back pain…
…
Ms Small has had a successful recovery from her injuries listed [contusion of face, scalp & neck except eye(s) (left), neck sprain, sprain of shoulder and upper arm (left) (shoulder only) and contusion of hip & thigh (left)] as she is currently working in a different section of the AFP at normal duties and hours…”[68]
[68] BT24 folios 167-168.
On 16 and 31 January 2017, 21 February 2017 and 6 March 2017, Dr Martin certified that Ms Small’s fitness for work was subject to medical restrictions.[69]
[69] BT34 folios 241-242, 244-245, 247-248 and 250-251.
Dr Martin was not called to give evidence, so it is not possible to test whether the medical restrictions he certified related to Ms Small’s accepted injuries arising from the 9 February 2016 incident. The report of her treating physiotherapist, James Olsen, is dated 30 June 2016,[70] and this does not illuminate the focus of treatment in March 2017. Mr Olsen was not called to give evidence, so I can go no further with his report.
[70] AT40.
On 21 March 2017, Comcare decided that Ms Small was not entitled to compensation under s 16 and s 19 of the SRC Act in respect of the injuries she sustained on 9 February 2016 for which Comcare accepted liability.[71] This decision was affirmed on reconsideration.[72] Ms Small applied for further review – application 2017/3099.
[71] BT30.
[72] BT33.

On 19 June 2017, Dr Bodel provided a medico-legal report to Ms Small.[73] The doctor was briefed with a large volume of materials and reported that –
“The diagnosis here is a soft tissue injury to the lower part of the back as a result of the original fall that occurred on 24 March 2009… Investigations at the time of that fall showed pre-existing pars interarticularis defects with a grade 1 spondylolisthesis at the lumbrosacral region. There was no definite clinical evidence of additional structural damage and the pars defects were not caused by the fall but they certainly have been aggravated by the fall. There was also evidence of probable minor disc injury at the L5/S1 level but no significant disc pathology at the L4/5 level at that time.
The subsequent event in May 2011 did cause further aggravation of that pathology in the lumbrosacral area for which she was still having intermittent treatment and review by the local doctor. Additional structural damage did occur in that episode with damage to the L4/5 disc in my view.
The subsequent event on 9 February 2016 has caused further soft tissue aggravation, a period of unconsciousness, an injury to the neck and the left shoulder and arm and further aggravation in the lower part of the back without any definite clinical evidence of major additional structural damage in the lumbrosacral region as a result of that event.
…
This lady does continue to suffer with the condition of injury caused by the initial event in March 2009, the subsequent injury in May 2011 and the most recent event on 9 February 2016.”
[73] Exhibit 3, page 13.
Dr Bodel gave extensive oral evidence, to which I will return.
Dr Bodel and Dr Mourad conferred privately before giving their oral evidence. For this purpose, and with the agreement of the parties’ legal representatives, they were briefed by the Tribunal about the thrust of Ms Small’s oral evidence and provided with a series of questions to be addressed. Each doctor marked up the question sheets. Those documents were taken into evidence – Dr Bodel’s responses are in Exhibit 4 and Dr Mourad’s responses are in Exhibit 8. As can be seen from those documents, much is agreed by Dr Mourad and Dr Bodel and the points of difference between them are narrow, but significant. Dr Bodel maintains that Ms Small sustained permanent disc damage at the L4/5 and L5/S1 levels when she fell on 24 March 2009 and on 18 May 2011. Dr Mourad does not agree and attributes the apparent disc pathology at those levels to Ms Small’s underlying and previously existing lytic spondylolisthesis.
Substantive issues raised by the applications
The issues for determination are –
(a)application 2016/2522:
(i)did the 24 March 2009 injury to Ms Small’s lower back resolve on or before 24 September 2010; and
(ii)was this injury an operative and effective cause of incapacity, and did it require medical treatment, on and after 18 May 2011 to 15 April 2016?
(iii)In order to answer these questions, it is necessary to determine
a -the nature and incidents of the initial injury to Ms Small’s lower back on 24 March 2009, including any pathological changes and resulting symptoms; and
b -whether reports of increased symptomatology in September 2010, October 2010, November 2010, April 2011 and May 2011, particularly on 24 September 2010 and 18 May 2011, are attributable to pre-existing L5/S1 spondylolisthesis or to physiological changes or traumatic incidents that occurred.
(b)application 2016/3803:
(i)did Ms Small sustain a fresh injury to her lower back on 9 February 2016 for which Comcare is liable to pay compensation?
(ii)In order to answer this question, it is necessary to determine if -
a -the low back and lower limb symptoms Ms Small complained of after falling on 9 February 2016 are properly attributable to a previously existing medical condition or the initial injury; and
b -the claimed injury arose out of, or in the course of her employment; and if so
c -the symptoms complained of are a ‘disease’ for the purposes of s 5A of the SRC Act, being an ailment to which the employment contributed to a significant degree; and if not
d -the symptoms are attributable to a physiological change such that an ‘injury (other than a disease)’ occurred.
(c)application 2017/3099:
(iii)did the injuries Ms Small sustained on 9 February 2016 for which Comcare accepted liability resolve on or before 21 March 2017, such that on that day, or thereafter to the present, compensation is not payable in respect of medical treatment expenses under s 16 of the SRC Act, or in respect of incapacity for work under s 19 of that Act?
Did the 24 March 2009 injury to Ms Small’s lower back resolve on or before 24 September 2010?
In Ms Small’s submission, she sustained a soft tissue injury to her lumbar spine in the 24 March 2009 fall. She contends that the soft tissue injury included internal disruption of the L4/L5 disc and the L5/S1 disc. These physiological changes, she admits, were not confirmed by radiological investigations at the time in the form of an X-ray, and no MRI or CT scan was undertaken until June 2011 – this reveals disc bulges and annular tears in the L4/L5 and L5/S1 discs. Nonetheless, relying on the clinical judgement opinion of Dr Bodel, Ms Small maintains that the internal disc disruption was a permanent change that is consistent with her subsequent symptoms.
Comcare contends that Ms Small’s low back injury resulted from blunt force trauma when she fell from the horse on 24 March 2009. The injury, so the argument goes, was in the form of a contusion or sprain affecting the soft tissues outside the vertebral column, with no disc disruption or spinal involvement. Comcare relies on the expert evidence of Dr Mourad in asserting that previously existing lytic spondylolisthesis at the L5/S1 level in Ms Small’s spine, and related degenerative disc pathology at the L5/S1 and L4/L5 levels, were unaffected by the fall – they were asymptomatic before and after the fall, and they remained asymptomatic until September 2010. Comcare relies on Dr Mourad’s evidence that Ms Small’s lytic spondylolisthesis would certainly become symptomatic at some point, and that the onset of symptoms noted by Dr Tang on 25 September 2010 is consistent with this occurrence – gradual onset following a period of increased exercise.
In Comcare’s submission, Ms Small’s evidence of experiencing leg pain immediately after the fall and over subsequent months to September 2010 should not be accepted. This is because the contemporaneous clinical notes of her treating general practitioner, Dr Tang (and others), and the clinical notes of The Canberra Hospital do not contain any reference to symptoms of that kind. Comcare asserts that the contemporaneous notes provide a more reliable record of symptoms and presenting complaints than Ms Small’s memory, which may be affected by the effluxion of time and some conflation, albeit perhaps unwitting, of historical symptoms eight years ago.
Comcare also contends that Ms Small’s March 2009 soft tissue low back injury resolved entirely by November of that year, after which there is no reliable report of low back or lower limb symptomatology until 25 September 2010. Comcare maintains that the symptoms Ms Small complained of on 24 September 2010 arose on the back of increased exercise, unrelated to her 2009 injury. On Dr Mourad’s evidence, exercise was a risk factor that may have rendered her spondylolisthesis symptomatic. The clear report of low back symptoms radiating into her lower limbs, and the subsequent episodic increase in symptomatology, in Comcare’s submission, is consistent with this occurrence.
Comcare’s case is essentially that, without hard evidence, post hoc medical assumptions drawn from the subjective history Ms Small reports must be treated with caution. In Comcare’s submission, the proposition that the 24 March 2009 fall caused physiological changes to her lumbar spine is no more than a hypothesis which is not consistent with, and is not supported by, reliable medical evidence and robust medical science. In support of this contention, Comcare points to alleged inconsistencies between Ms Small’s evidence and contemporaneous medical records; alleged flaws or deficiencies in Dr Bodel’s evidence; and deficiencies in the evidence and reports of other medical specialists and experts that go to weight, including, for example, in relation to the extent of briefing materials provided, the scope of the reports provided, the currency of examinations and reported opinions, and the relative qualifications of the particular doctors.
Furthermore, Comcare asserts that Ms Small’s representations in the press[74] in respect of her claimed injuries are misleading and intended to influence the Tribunal. This, Comcare says, indicates the unreliability of her evidence.
[74] See Exhibit 12.
Pressing these and other extensive submissions made during the hearing, Comcare says Ms Small’s injury had resolved before 24 September 2010. For these reasons, Comcare asserts that the revocation decision is correct and it should be affirmed.
As will appear, I do not agree. There are two key reasons for this.
Firstly, I accept Ms Small as a witness of truth, and her evidence of low back pain continuing episodically but always in the same location after her 24 March 2009 injury is compelling. I do not accept Comcare’s submissions that the representation of her case in the public media is something she sought out, and I do not think it is appropriate to measure her credit against the words used to describe her condition and her circumstances in the article placed before the Tribunal (of which I was not previously aware) – those are the words of a journalist who was not called to give evidence.
Secondly, I prefer the evidence of Dr Bodel and Dr Le Leu, and their consistent explanations of the nature of Ms Small’s low back injury, to the evidence of Dr Mourad and his explanations of her low back symptoms. The evidence of Dr Bodel and Dr Le Leu is substantially consistent with the preponderant weight of the present medical evidence.
The matter is to be decided on balance of probabilities, applying the reasonable satisfaction standard of proof, for the purposes of the SRC Act.
Comcare makes much of descriptors the experts use in their evidence: possibility versus probability. There are two things to say about this. Firstly, it is for the Tribunal to decide if the evidence is sufficient to meet the legal standard of proof it must apply - the civil standard of reasonable satisfaction on the balance of probabilities. Secondly, this test does not turn on a medical expert simply using words such as ‘probable’ or ‘possible’ on medical grounds. Just as an expert describing a point of opinion as ‘probable’ does not make it so, an expert describing a hypothesis as ‘possible’ does not exclude it from proper consideration. More is required to meet the legal test.
The Tribunal must satisfy itself that the particular point is established on the balance of probabilities, and in so doing it must consider all the relevant materials placed before it. Even though there may be degrees of probability within the civil standard and “the strength of the evidence necessary to establish a fact or facts on the balance of probabilities may vary according to the nature of what it is sought to prove”,[75] there is “a distinction of substance to be drawn between probabilities on the one hand and mere possibilities, even if they are real as distinct from fanciful, on the other”.[76]
[75] Neat Holdings Pty. Limited V. Karajan Holdings Pty. Limited and Ors (1992) 110 ALR 449, per Mason C.J., Brennan, Deane and Gaudron JJ at [2].
[76] Repatriation Commission v Smith (1987) 74 ALR 537.
This is not a matter of choosing between guesses or theories, on the basis that one seems more likely than another.[77] As Gordon J said in Re Day[78] at [15] to [17] -
“However, the seriousness of an allegation made, the inherent unlikelihood of an occurrence of a given description, or the gravity of the consequences flowing from a particular finding are considerations which must affect the answer to the question whether an issue has been proved to the reasonable satisfaction of the tribunal. Where, as here, fraud is alleged, "reasonable satisfaction" is not produced by inexact proofs, indefinite testimony, or indirect inferences. This does not mean that the standard of persuasion is any higher than the balance of probabilities. It does mean that the nature of the issue necessarily affects the process by which the reasonable satisfaction is reached.
Why? There is a conventional perception that members of society do not ordinarily engage in fraudulent conduct and a court should not lightly make a finding that, on the balance of probabilities, a party to civil litigation has been guilty of such conduct.
The nature of the allegation requires, as a matter of common sense, the careful weighing of testimony, the close examination of facts proved as a basis of inference and, on appeal, a comfortable satisfaction that the tribunal reached both a correct and just conclusion.
The tribunal must feel an actual persuasion of the occurrence or existence of a fact before it can be found. Where direct proof is not available and satisfaction of the civil standard depends on inference, "there must be something more than mere conjecture, guesswork or surmise" – there must be more than "conflicting inferences of equal degrees of probability so that the choice between them is [a] mere matter of conjecture". An inference will be no more than conjecture unless some fact is found which positively suggests, or provides a reason in the circumstances particular to the case, that a specific event happened or a specific state of affairs existed.”
[Citations omitted]
[77] Jones v Dunkel (1959) 101 CLR 298 at 305.
[78] (2017) 340 ALR 368.
Nature of the 2009 injury
If medical science is as black and white as Comcare contends, cases of this kind would be addressed in very short order. But it is in cases like this that the limit of medical science is quickly encountered, beyond which little is sharply defined in black and white, and clinical judgement, plausible theory, open possibility and sheer conjecture (or guesswork) arise in varying shades of grey.
It is quite clear that Dr Mourad and Dr Bodel recognise this in their agreement that, without an MRI scan being taken on 24 March 2009, it is not possible in retrospect, several years later, to be certain whether or not disc pathology at the L4/L5 and L5/S1 levels was present at the time – damage to discs does not appear on plain X-ray.[79] The best one can do is to closely examine the X-ray films for abnormalities, such as changes in alignment, fractures or loss of disc height for example. That is what Dr Mourad and Dr Bodel did in Ms Small’s case.
[79] See X-ray report at AT4 folio 16; T5 folio 20 refers.
Where the X-ray is inconclusive, and I understand that both experts consider it to be so in respect of a soft tissue injury to Ms Small’s lower spine on 24 March 2009, then it is necessary to form a clinical judgement or opinion based on a medical examination of the person, the person’s relevant medical history, and careful consideration of relevant contextual materials, including subsequent imaging and medical records. Formulating an assessment of this kind in retrospect becomes more difficult with the effluxion of time. Nevertheless, this, too, is what Dr Mourad and Dr Bodel have done; and each doctor has considered a voluminous amount of contextual material.
In the result, however each expert’s evidence is dressed up, both doctors have presented explanations or rationales drawn from their medical expertise and their clinical judgement regarding the condition of Ms Small’s lumbar spine on 24 March 2009, including the nature and incidents of her injury on that day, and the cause of subsequent symptoms.
Comcare prefers Dr Mourad’s explanation, and attacks Dr Bodel’s explanation of Ms Small’s low back symptoms from 24 March 2009 on the basis of damage to her L4/L5 disc when she fell from the horse as a hypothesis in the realm of possibility, without a clear rationale or hard data in the form of contemporaneous radiological evidence to support it. To my mind, the same may be said about the explanation Dr Mourad provided.
Dr Mourad’s explanation raises several possibilities. The L4/L5 and L5/S1 disc pathology reported in the 14 June 2011 MRI would have been present and asymptomatic when Ms Small fell from the horse on 24 March 2009. The symptoms caused by the fall (of persisting but variable pain at or about the L4/L5 level) were unrelated to the L4/L5 and L5/S1 pathology, but were produced by damage to soft tissues outside the vertebral column. Those symptoms entirely resolved before similar symptoms arose in the same region of Ms Small’s lumbar spine several months later. And those later symptoms arose from her previously asymptomatic spondylolisthesis and related disc pathology, without trauma, but after a period of increased exercise. The proposition that Ms Small’s L5/S1 spondylolisthesis was unaffected by the fall from a horse on 24 March 2009, but became symptomatic after a period of increased exercise in September 2010 is a matter of opinion – it is a possibility, without contemporaneous ‘hard data’ to support it.
As I have said, when faced with two plausible hypotheses, the Tribunal cannot simply choose between possibilities, on the basis that one is more likely than another. It must assess all of the materials before it and satisfy itself about relevant factual matters. Ultimately in a case of this kind, if the materials are not sufficient to enable the Tribunal to be reasonably satisfied about a crucial matter necessary to establish the factual basis of a claim or to upset the status quo, whatever that may be, the status quo will remain in place.
It is necessary to carefully consider the evidence and the precise sequence of events. Ms Small’s fall from a horse on 24 March 2009 was witnessed by her (then) supervisor, Kylie Woodyatt, who produced a Workplace Incident Report, which states –
“[Ms Small was jumping her work horse Bikkardi, on landing after the jump he stopped threw his head and hit [Ms Small] in the face. [Ms Small] then fell to the ground landing on her side and then rolling over onto her back. Immediately after [Ms Small] started complaining of feeling dizzy and wanting to throw up!...”[80]
[80] T4 folio 17.
As can be seen, this account does not refer to Ms Small falling onto her head or being rendered unconscious. Ms Woodyatt’s report of Ms Small complaining of dizziness and nausea ‘immediately after’ the fall might be consistent with Ms Small being briefly rendered unconscious. The words ‘immediately after’ in this context are ambiguous and open to a number of interpretations. Ms Woodyatt was not called to give oral evidence so these matters could not be tested.
The Canberra Hospital clinical records include the following notes –
“Fall from horse, approx 2m. breif [sic] LOC. wearing since then headache, nauseated but nil vomiting, stated was head butted by hoprse [sic] twice, then fell off...”[81]
“21 who is a policeman was riding a horse today – show jumping. Over jump. Head hit the back of horse and then fell down.
She got up and tried to ride again. Very brief LOC for a few seconds.”[82]
“Mechanism: Show jumping 16 hand horse over jump → hit head on horse’s neck ?LOC then thrown… landing on head, shoulder → wearing helmet”[83]
[81] Exhibit 15, page 1.
[82] Ibid, page 3.
[83] Ibid, page 4.
Ms Small’s account is largely consistent with these records, although she says that she lost consciousness after falling – she recalls seeing the horse’s legs as she fell.
On balance, I am reasonably satisfied that Ms Small was thrown in the manner described and that she fell on the left side of the horse and landed on her head, right shoulder and right side, and then rolled onto her back. I accept that she lost consciousness for a brief period – the symptoms recorded by the Calvary Hospital are consistent with that occurrence.

The symptoms she complained of on admission to the Canberra Hospital are set out in the clinical records. These include headache, painful right jaw, neck pain and tenderness on palpitation, right shoulder and right upper limb pain with reduced range of motion, and lower lumbar pain and tenderness.[84] A diagram recording physical findings shows an area of tenderness over the lower lumbar spine and a right facial laceration.[85] Weakness in her legs was also noted.[86]
[84] Ibid, pages 1-7.
[85] Ibid, page 5.
[86] Ibid, page 17.
It appears that the lumbar symptoms were assessed and the notes record “L spine cleared by XR”.[87] The X-ray report states:
“There is a probable Grade 1 spondolytic spondylolisthesis at the L5-S1 level. No acute fractures or vertebral body displacement is seen. The paravertebral soft tissues are normal…”.[88]
[87] Ibid, page 8.
[88] AT4 folio 16.
It appears that Ms Small remained in hospital for a number of days. On 26 March 2009, the notes record that Ms Small “reports pain is > in neck – central, lower back & R UL – legs “stiff” on walking”.[89] The discharge report states –
“She presented to the Emergency Department after being thrown from her horse. She reports hitting her head ?LOC and significant paraspinal cervical and lumbar spine pain.
Primary survey was unremarkable apart from paraspinal pain. Secondary trauma survey demonstrated a tender right proximal forearm.
… CT Brain, C-spine, CXR, Pelvis and Xray lumbrosacral spine were normal…”[90]
[89] Exhibit 15, page 15.
[90] Ibid, page 22.
On this evidence, and as the discharge referral records reveal,[91] it is clear enough that Ms Small’s symptoms are consistent with a soft tissue injury in the area of her lumbar spine. Doing the best with these records, and carefully assessing the subsequent evidence, including that given by Dr Mourad, Dr Bodel and Dr Le Leu in the hearing, I am satisfied that the soft tissue injury was at or about the L4/L5 level – the records suggest symptoms above the L5/S1 level at the base of her spine.
[91] Ibid, page 25.
The precise nature of the soft tissue injury, however, is not clearly identified in the contemporaneous records. And on this point the expert opinions diverge.
Dr Mourad says the injury was in the soft tissues outside the vertebral column, without involvement of any spinal structures. He considers that the blunt force of Ms Small falling from the horse onto her side would not have been sufficient to damage spinal structures or deep tissues, and in his opinion no axial forces would have arisen sufficient to cause compressive damage to a disc. I understand the doctor’s reference to ‘axial force’ to mean compressive force in the vertical axis of the vertebral column. Furthermore, he gave evidence that leg raising would not be consistent with an injury to the L4/L5 disc.
Dr Bodel is of the opinion that the forces involved would have been sufficient to impact upon the L4/L5 disc and cause soft tissue damage in the form of an “internal disc disruption”. He also reported the possibility of L5/S1 disc damage. As I understand the doctor’s evidence, damage of this kind may be caused by sudden traumatic force. This, in his opinion, is consistent with the symptoms Ms Small described immediately after the fall.
Both opinions are plausible. Neither opinion is proved or disproved by the contemporaneous materials. Nevertheless, Dr Bodel’s explanation of the mechanism by which disc damage might occur is consistent with and supported by the evidence of Dr Le Leu, Dr Wilkins, Dr Stokes and Dr Low. Furthermore, Dr Bodel’s explanation of Ms Small’s symptoms of low back pain as discogenic is consistent with Dr Pik’s subsequent report (albeit after the fall on 18 May 2011). Dr Pik reported the possibility of L5 par defects contributing to her pain symptoms and some reproduction of pain at this level in the discogram procedure, albeit at a lower correlate level than for the L4/L5 disc. Dr Mourad’s evidence about the significance of leg raising to contra-indicate an injury to the L4/L5 disc is not consistent with the report of Dr Pik. As Dr Pik is a neurosurgeon who examined Ms Small twice in a treatment context, his evidence is preferred on this point.
I accept Ms Small’s evidence that after the fall on 24 March 2009 she continued to experience centrally located low back pain and related symptoms in varying degrees of intensity – the pain varied in degree, but it was always in the same location, around the L4/L5 level where she first experienced pain immediately after falling from the horse in March 2009. Ms Small struck me as a witness of truth, who gave her evidence in a forthright manner to the best of her recollection. I am satisfied that these symptoms were centrally located at about the L4/L5 level in her lumbar spine and they were as a result of falling from the horse on 24 March 2009.
Furthermore, her evidence on this point is supported by the 10 May 2011 report by Dr Tang that “Her pain did not bother her much from September 2009 to 25 September 2010”[92] and the reference of back pain in the emBODYment Pre Exercise Questionnaire on 3 August 2010.[93] It is also consistent with the Calvary Hospital clinical notes on 18 and 19 May 2011 which record “LBP since ~2009 from fall from horse” and “longstanding history of LBP”.[94] I note that the Calvary Hospital clinical note on 24 September 2010 records “c/o back pain onset this pm , Past hx of back injury March 2009 after falling from a hoarse” and “PMH [patient medical history] – CHRONIC BACK PAIN FROM BACK INJURY”.[95]
[92] T17 folio 73.
[93] Exhibit 15, page 27.
[94] Ibid, pages 46 and 47.
[95] Ibid, pages 34 and 35.
Comcare asserts that Dr Tang’s report is not entirely consistent with clinical notes he produced, in which he does not refer to back pain or related symptoms in the period from November 2009 until the report of symptoms on 25 September 2010. As I have said, the doctor was not called to explain this discrepancy. One would expect that the doctor prepared his report with regard to clinical notes and his knowledge of Ms Small’s symptomatology, and I will proceed on that basis. For this reason, I accept his report is an accurate account of his knowledge of Ms Small’s presenting low back symptoms.
I am satisfied, and find, that Ms Small’s low back injury did not completely resolve in the six to eight months after 24 March 2009, as Comcare contends and Dr Mourad suggests. The Insight Rehabilitation reports, including the closure of her rehabilitation program and her return to full pre-injury duties do not compel any different conclusion.
The proposition that Ms Small’s low back symptoms gradually resolved thereafter over time, as reported by Dr Pik, is somewhat consistent with her evidence that there were periods in which she was not troubled by low back pain symptoms in the period from November 2009 to September 2010. It is curious that Dr Pik does not refer to flare ups of low back pain and leg pain in the period from September 2010 to May 2011 – it is quite clear that these occurred. But the doctor was not called to give evidence and the extent of the history he was given by Ms Small cannot be examined or tested.
While Dr Mourad and Dr Bodel disagree about the cause of disc pathology at the L4/L5 and L5/S1 levels in Ms Small’s lumbar spine, whether caused by the falls she sustained or developmental L5/S1 anterolisthesis, the doctors agree that any resulting symptoms would likely follow an episodic course. It does not follow from this, however, and it should not be assumed, that the underlying cause can be taken to have resolved in the periods between episodes. If it is established by evidence that the episodic symptoms are the result of persisting pathology resulting from an injury, then it may properly be said that the injury persists between symptomatic episodes. That, I am satisfied, is what occurred in Ms Small’s case.
On balance, Ms Small’s low back symptomatology in the period from 24 March 2009 to 24 September 2010 is more consistent with Dr Bodel’s explanation of a soft tissue injury in the form of internal L4/L5 disc disruption, than it is with that proposed by Dr Mourad of injury to the soft tissues surrounding the vertebral column, without spinal involvement. Dr Mourad’s opinion turns on the complete resolution of low back symptoms within several months of injury, as one might expect with a soft tissue injury of the kind he reported. But the evidence points to the continuation of variable symptoms centrally located at or about the L4/L5 level, suggesting that some spinal involvement is likely.
Considering all the relevant materials, I am reasonably satisfied that Ms Small’s low back symptoms from 24 March 2009 were discogenic in nature and located at the L4/L5 level.
I note at this point Dr Mourad’s evidence that, in his opinion, the L4/L5 disc protrusion that was confirmed in the MRI taken on 14 June 2011 was likely to have been present on and before 24 March 2009. This, he explained, is because it was the likely result of degenerative changes in Ms Small’s lumbar spine consequent to her spondylolisthesis. In his opinion, the spondylolisthesis and related defects in the L5 pars interarticularis were the result of serial microtraumas associated with upright bidpedal locomotion and horse riding, and these changes, albeit asymptomatic before and after the fall on 24 March 2009, would be strongly correlated with degenerative changes in the L4/L5 and L5/S1 discs. He pointed to two research reports in support of this assessment, in which a 100 percent correlation between listhesis of 15 percent or more and degenerative disc changes at related levels. There are three immediate difficulties with this evidence.
Firstly, the present evidence does not establish that Ms Small’s anterolisthesis is 15 percent or more, although that possibility lies open. Dr Bodel measured the films of X-rays taken on 24 March 2009 and 26 April 2013 and reported the degree was 9 percent in the former and a little over 10 percent in the latter, within the margin of error. Dr Mourad measured a photograph he took of the 24 March 2009 X-ray using his mobile telephone and reported the degree of slippage was 16 percent. There are open questions about how each expert took the measurements reported and whether or not, or to what extent, the results are reliable.
Secondly, broad research findings of the kind referred to by Dr Mourad are not very helpful in addressing the specific factual issues in this case. As is common when research of these kinds is relied upon to support an expert’s opinion, the basis on which the research was conducted, including the characteristics of the subject cohort, and a host of other variables, come into question. I do not propose to go any further on this point than to observe that great caution is required when seeking to apply broad research findings in respect of medical hypotheses to the specific circumstances of a particular case.
Thirdly, even if one was to accept and apply the research findings underpinning Dr Mourad’s opinion, the reported correlation between asymptomatic spondylolisthesis and disc degeneration does not shed any light on symptomatology – when and in what circumstances, or by what processes, symptoms arising from spondylolisthesis and related disc damage occur. Clearly, there are many variables in each case that bear upon the emergence of symptoms.
Dr Mourad accepted that the existence of lower limb symptoms would be significant – from this I understand him to mean that this may signify some spinal involvement. The contemporaneous notes of the Canberra Hospital immediately after Ms Small’s fall on 24 March 2009 do not record complaints of lower limb pain, but there is a record of lower limb weakness. The cause of this symptom is not explained.
Dr Mourad conceded that he would not expect spondylolisthesis and related degenerative processes to become symptomatic in the first two or three decades of life, but Ms Small’s spondylolisthesis became symptomatic when she was 23 years old. On his evidence, with Ms Small’s previously existing spinal pathology and her history of horse riding from childhood, this was inevitable. There are a number of difficulties with this evidence. Dr Mourad, Dr Bodel and Dr Le Leu accepted that some people with spondylolisthesis do not experience symptoms. The basis of Dr Mourad’s opinion that Ms Small would inevitably develop symptoms of her spondylolisthesis is somewhat speculative. As I understand it, this turns on horse riding as a causal factor of Ms Small’s L5 pars defects and her subsequent involvement in exercise. His evidence is that her spondylolisthesis did not become symptomatic when she fell from the horse on 24 March 2009, rather it became symptomatic, without trauma, after a period of exercise in September 2010 – exercise, in his opinion, was a risk factor for such an occurrence in Ms Small’s case. Conceivably, Dr Mourad is right about exercise being a risk factor, but there is evidence that Ms Small benefitted from managed exercise before and after 24 September 2010, and that managed exercise was part of the medical treatment of her lumbar spine condition.[96]
[96] See, for example, T15 folio 69, T38 folio 165, T42 folio 188 and 190, T49 folio 218, T58 folio 233, T65 folio 258, AT8 folio 31, AT9 folio 32 and AT10 folios 34-36.
Furthermore, Dr Pik’s evidence, which I accept, establishes the strong probability that her pain symptomatology was discogenic in origin, involving the L4/L5 disc, and only possibly related to the L5 pars defects. This does not support Dr Mourad’s assessment that Ms Small’s spondylolisthesis was responsible for her low back pain symptoms from September 2010.
In sum on this point, Dr Bodel’s explanation is consistent with Ms Small’s symptomatology after 24 March 2009, and it is supported by subsequent MRI imaging and medical reports. Dr Mourad’s explanation stands alone and it is not preferred.
I am reasonably satisfied that Ms Small’s 2009 low back injury did not resolve before 24 September 2010.
Much was said during the hearing about Ms Small’s account of pain radiating into her legs from March 2009.
It is possible that Ms Small experienced some leg pain immediately after falling from the horse in March 2009, but the absence of contemporaneous medical records of any such complaint is troubling. It is conceivable, as she asserts, that she reported symptoms of this kind but they were simply not recorded. To my mind, it is unlikely that such an oversight would have been repeated by so many doctors and other medical officers, including doctors and nurses at the Canberra Hospital and her treating general practitioner. The only lower limb symptom recorded at the time was of weakness. Whether Ms Small is correct in her present account, or she has conflated symptoms experienced some years ago, as Comcare contends, I cannot reliably determine. As I have said, Ms Small struck me as a truthful witness.
Nevertheless, to my mind, little turns on this. If she did not experience lower limb pain from March 2009 to September 2010, this would not rule out spinal involvement or the existence of L4/L5 discogenic pain. Conversely, if there was clear evidence of pain radiating into her legs on and after 24 March 2009, this would be one indicator of spinal involvement, but it is not the only indicator. The nature, persistence and consistent location of her low back pain symptoms over a long period also indicate spinal involvement. And this is consistent with an injury to the L4/L5 disc on 24 March 2009.
Was the 2009 low back injury an operative and effective cause of incapacity, or did it require medical treatment, on and after 24 September 2010 and 18 May 2011 to 15 April 2016?
Ms Small asserts that the 2009 injury has resulted in episodic flaring of symptoms ever since and the proposition that the episodes from 24 September 2010 to 18 May 2011 have a different cause is not made out.
Comcare argues that Ms Small experienced fresh symptoms on and after 24 September 2010, or that she suffered an aggravation that overtook and completely replaced any lingering symptoms from the 2009 injury, and thereafter her 2009 injury was not an operative or effective cause of incapacity. It is for this reason that Comcare asserts that Ms Small is not entitled to compensation in respect of her 2009 injury from 18 May 2011.
In Comcare’s submission, the incident on 18 May 2011 (or the preceding incident on 24 September 2010) was sufficient to constitute a novus actus interveniens by which the causal chain linking subsequent incapacity to the 24 March 2009 injury was severed.
As will appear, I am satisfied that Comcare’s submissions on this point are not made out.
The incapacity Ms Small experienced on and after 24 September 2010 and 18 May 2011 may have resulted from different causes. This is not disentitling, however.
It is well settled law that the causal connection between an injury and subsequent incapacity or impairment described by the words ‘as a result of’ is not one of exclusivity should multiple causal factors be present[97] – “it is sufficient if the injury contributes in a material sense to the incapacity…If a compensable injury constitutes one of a number of factors or events each of which combine as links in a chain of causation terminating in a single condition amounting to total incapacity, that incapacity will be fully compensable, the injury being a contributing cause in a material sense”.[98]
[97] Comcare v Martin [2016] HCA 43 at [45].
[98] Commonwealth of Australia v (K C) Smith (1989) 18 ALD 224 at 226.
Having regard to the statutory text and purposes, the test then is whether the claimed incapacity or impairment, and the obtaining of medical treatment, can properly, fairly, be attributed to the previous injury, or whether intervening events are such that the attribution should be made to the new cause. This requires an assessment of the cause or causes of the incapacity or impairment, and the extent to which the previous injury is an effective and operative contributing factor. If it is, then the resulting incapacity or impairment may truly be said to result from the injury. When making an assessment of this kind, it is necessary to closely examine the detailed facts and the evidence, and to apply the test the legislation provides according to its purposes. If common sense plays any part, beyond a detailed assessment of the facts and the evidence, it may only do so within the statutory frame.[99]
[99] Comcare v Martin [2016] HCA 43 at [42].
The contemporaneous medical records reveal the sequence of events on 24 September 2010.[100] She was exercising in order to lose weight and experienced niggling low back pain for several days. On the day in question, she returned home and experienced a ‘click’ in her lumbar spine when descending some stairs in her home. This was associated with sudden onset of low back pain with pain radiating into her legs.
[100] T77 folio 516 and Exhibit 15, page 312; T17 folio 73 refers.
The sequence of events on 18 May 2011 is as follows. Ms Small sought medical treatment for “niggling” low back symptoms - the clinical notes recorded at about 3pm on that day refer to her “sitting for 12”.[101] Ms Small’s account is that she underwent some exercise and then returned home that evening, but felt a ‘click’ in her lumbar spine when ascending some stairs and her legs collapsed, causing her to fall backwards down the stairs. There is a controversy over the Calvary Hospital notes insofar as they are not consistent with Ms Small’s account. The notes record –
“felt a click in LB
landed on lower back+ hit occiput but no lOC
able to get up but immediate shooting pain down backs of legs
ongoing bilateral sciatica
…”[102]
and
“slipped and fell down 4 steps tonight at 2030hr; able to get up, but felt a ‘click’ in her lumbar back and had immediate onset of severe bilateral ‘sciatica’ distribution pain down to level of ankles
…”[103]
[101] Exhibit 15, page 391.
[102] T77 folio 507.
[103] Ibid folio 508.

I do not accept that the Hospital notes are an accurate representation of the precise sequence of events. As can be seen, the notes are inconsistent – one refers to a ‘click’ in her lumbar back followed by Ms Small falling down the stairs and then sudden onset of pain on rising to stand, whereas the other refers to Ms Small slipping and falling down the stairs, after which she was able to get up but she then experienced a ‘click’ in her lumbar back associated with sudden onset of pain.
Dr Mourad and Dr Bodel could not provide an explanation of what caused Ms Small’s lower back to ‘click’, but this was not considered by either doctor to be significant.
Dr Bodel explained that the sudden collapse of Ms Small’s quadriceps muscles, causing her to fall would be consistent with spasm resulting from spinal pathology in her lumbar spine, much as had occurred previously with the episodic flaring of symptoms attributable to her 24 March 2009 injury. Dr Bodel’s evidence is that the episodes of increased low back symptoms Ms Small experienced from September 2010 to May 2011 resulted from the 24 March 2009 injury – this injury continued to affect her throughout this period. Furthermore, on Dr Bodel’s evidence, the sudden onset of more severe low back pain and pain radiating into both legs on 18 May 2011 was the result of further structural damage to Ms Small’s lumbar spine when she landed on her lower back at the foot of the stairs – possibly to the L4/L5 and L5/S1 discs.
Dr Mourad gave evidence that physical exercise and the underlying L5/S1 spondylolisthesis were the likely reasons for the emergence of low back and lower limb symptoms in September 2010. Dr Mourad explained Ms Small’s symptoms on 24 September 2010 and 18 May 2011 as exercise-related provocations of her previously asymptomatic but underlying L5/S1 spondylolisthesis, albeit without any further pathological changes in her lumbar spine.
Dr Mourad’s opinion is difficult to reconcile with the reported benefit Ms Small obtained from managed physical exercise[104] over a long period. It can be accepted, however, that horse riding placed stress on Ms Small’s lower back and that her history of riding horses may have contributed to pars defects at the L5 level and consequently to the anterolisthesis at the L5/S1 level. In Dr Mourad’s opinion, disc pathology at the L4/L5 and L5/S1 levels, in the form of posterior bulges and annular tears that were noted when an MRI scan was taken in June 2011, related to this history, and they were present before 24 March 2009.
[104] T15 Folio 69
Dr Mourad gave evidence that he measured the degree of L5/S1 slippage in the 24 March 2009 X-ray and gave evidence that this was 16 percent and it did not change subsequently. I note that Dr Mourad measured the degree of slippage using a photograph he took of the original X-ray film from 24 March 2009.
Dr Bodel measured the actual film and the film of the X-ray taken in 2013 and gave evidence that the degree of slippage was 9 percent in March 2009 and a little over 10 percent in 2013 – this difference was within the margin of error and does not represent further slippage.
The amount of slippage of L5 on S1 was reported in the 2011 MRI scan to be 2-3 millimetres.[105]
[105] T20 folio 78.
It is not presently established that any change occurred in Ms Small’s spondylolisthesis or in the degree of slippage of L5 on S1 from 24 March 2009 to 18 May 2011, or thereafter.
I prefer Dr Bodel’s evidence on these points. His evidence, and the rationale on which his opinion rests, is consistent with the radiological material and the preponderance of medical evidence before the Tribunal. I am satisfied that the damage caused to the L4/L5 disc by the 24 March 2009 injury was of a permanent nature even though the symptoms were subject to fluctuation, even temporary resolution, and episodic flaring. This is consistent with Dr Le Leu’s evidence and the preponderance of expert medical opinion.
Dr Mourad’s hypothesis that Ms Small’s previously existing spondylolisthesis gradually became symptomatic after exercise in September 2010, without any pathological change taking place, is not persuasive. It is not consistent with the weight of the evidence before the Tribunal. It turns on the complete resolution of Ms Small’s 24 March 2009 injury and related symptoms. I have found that this did not occur.
I am reasonably satisfied that the episode of increased symptoms Ms Small experienced on 24 September was causally and materially the result of the injury she sustained on 24 March 2009. To the extent that it is possible that her previously asymptomatic spondylolisthesis became symptomatic or contributed in some way or to some degree, I am not persuaded that the contribution was such that it displaced or severed the causal link between the discogenic symptoms Ms Small experienced on 24 September 2010 and the 24 March 2009 injury.
I have reached the same conclusion in respect of incidents to which I have referred in the period from 24 September 2010 to 18 May 2011 – the present evidence does not positively establish that the chain of causation between Ms Small’s low back symptoms and the 24 March 2009 spinal injury was disrupted, severed, displaced or overtaken by a new cause of symptoms or incapacity.
I am satisfied that on 18 May 2011, when Ms Small fell backwards from the fourth step and landed on her lower back, the forces involved were sufficient to cause further damage to the L4/L5 and L5/S1 discs. Whether or not the fall was sufficient to apply axial forces to her lumbar spine, such as could be expected if she landed heavily on her bottom, is not entirely clear. Although, to my mind, several factors point in that direction.
On Dr Bodel’s evidence, the immediate change in the intensity and nature of Ms Small’s low back and lower limb symptoms would be consistent with damage of that kind. The persistence of these elevated symptoms would be consistent with a permanent structural change in her lumbar spine as reported by Dr Bodel and subsequently proved in the 2011 MRI scan which Dr Pik reported to show “dessication of the L4/5 intervertebral disc associated with decreased disc height and a minor non compressive [L4/L5] disc bulge”.[106]
[106] T50 folio 219.
The location of Ms Small’s low back pain from 24 March 2009 did not change, although the severity and frequency of episodes increased. The occurrence of intense and frequent radicular lower limb symptoms was a new development, and I am satisfied that this was not the result of Ms Small’s 24 March 2009 low back injury but rather fresh damage that was sustained when she landed on her lower back at the foot of the stair on 18 May 2011.
Nevertheless, on balance, it is more probable than not that Ms Small’s 2009 low back injury resulted in a permanent physiological change to her L4/L5 disc, albeit undetected by X-ray at the time, which continued to cause symptoms, incapacity for work and impairment, as well as requiring medical treatment, after 18 May 2011.
The weight of the medical evidence supports a finding that Ms Small’s symptoms in her lower back from 18 May 2011, and the resulting incapacity she experienced and medical treatment she obtained, were partly the result of the continuing effects of Ms Small’s 24 March 2009 injury and, in other part, related to further damage to her spine that was caused by her fall on 18 May 2011. I am satisfied that Ms Small’s 2009 low back injury was an operative and effective cause of impairment and incapacity on and after 18 May 2011, and it continued to require medical treatment.
I should say at this point, that the present evidence is not sufficient to permit the causes of incapacity after 18 May 2011 to be disentangled, such that a proportion or degree might be attributed to the different causal factors, which in all likelihood include the 2009 low back injury, the onset of lower limb symptoms in September 2010, the additional disc damage that resulted from the fall on 18 May 2011 and the continuing spondylolisthesis. Each of the factors would be expected to produce similar kinds of symptoms in Ms Small’s lower back, albeit to varying degrees from time to time. I can go no further with this issue on the present materials.
Consequently, I am satisfied that Ms Small remained entitled to compensation for incapacity and for medical treatment expenses in respect of her 2009 low back injury after 18 May 2011. And I am satisfied that the 2009 low back injury did not resolve prior to 25 September 2010.
From this it follows that the own motion reconsideration decision that is the subject of application 2016/2522 must be set aside.
There is one further matter to note at this point. The own motion reconsideration decision revoked a large number of primary determinations made in the period from 18 May 2011 to 25 April 2016. With the agreement of the parties, I have not reviewed each of those determinations, nor is it necessary to do so. By this decision, the revocations are removed and the original determinations stand.
Nevertheless, it is necessary to remit the matter to Comcare to determine Ms Small’s further entitlements to compensation in respect of her 24 March 2009 lumbar spine injury to the L4/L5 disc, if any.
Did Ms Small sustain a fresh injury to her lower back on 9 February 2016 for which Comcare is liable to pay compensation?
In order to answer this question, it is necessary to determine if -
(a)the symptoms complained of are a ‘disease’ for the purposes of s 5A of the SRC Act, being an ailment to which the employment contributed to a significant degree; and if not
(b)the symptoms are attributable to a physiological change such that an injury in the primary sense occurred and, if so
(c)the injury arose out of, or in the course of her employment such that it is within the meaning of an ‘injury (other than a disease)’.
Disease
Comcare argues there is no ‘disease’ that was significantly contributed to by Ms Small’s employment as result of the incident on 9 February 2016.
Ms Small maintains that she was injured in compensable circumstances, whether or not the injury is a ‘disease’ or an ‘injury (other than a disease)’ for the purposes of the legislation.
Under s 5A(1) and s 5B of the SRC Act, a disease is an ailment to which the employee’s employment contributed to a ‘significant degree’, as defined.
I am not persuaded that the increase in low back pain and pain radiating bilaterally into Ms Small’s legs is within the meaning of ‘disease’. This is because I am not persuaded that her employment significantly contributed to the increase in her symptoms.
It is quite clear that Ms Small’s symptoms were the result of her falling in a faint from standing. It was not her employment that caused her to fall – she experienced breathlessness and a vasovagal episode. The present evidence does not establish that this was significantly contributed to by her employment, or that her employment contributed in any way to the fall.
From this it follows that there was not a ‘disease’ arising from the 9 February 2016 incident.
Injury (other than a disease)
Under s 5A(1) of the SRC Act, an ‘injury (other than a disease)’ is one that has a physiological character, involving a physiological change or a disturbance of the normal physiological state of some kind, whether of sudden or gradual onset.[107]
[107] Military Rehabilitation and Compensation Commission v May [2016] HCA 19, per French CJ, Kiefel, Nettle and Gordon JJ at [52] and [57] to [62].
The present evidence does not establish, as a matter of probability, that Ms Small sustained any identifiable physiological change in her lumbar spine or related physiological structures and tissues when she fell on 9 February 2016.
It is more probable on the evidence of Dr Bodel, Dr Mourad, Dr Le Leu, Dr Stokes, Dr Low and Dr Martin that the fall did not result in additional structure damage caused to her lumbar spine and related structures and tissues. It is quite clear that there was a sudden increase in symptoms, but these occurred in the same locations and are described as similar to previous occurrences of episodic symptoms resulting from Ms Small’s previously existing (and persisting) pathology at the L4/L5 and L5/S1 levels.
On balance, I am reasonably satisfied that the increase in symptoms is properly attributable to her already existing lumbar spine condition and not to a new or changed physiological cause.
From this it follows that Ms Small did not sustain a fresh ‘injury (other than a disease)’, or an injury in the primary sense to her lower back on 9 February 2016.
As for the loss of sensation in her thighs – this implies a neurological component. Dr Le Leu gave evidence that this might suggest involvement of the femoral nerve, but the symptoms do not conform to a dermatonal distribution. This is a difficulty for Ms Small. The loss of sensation she described is not explained in terms that suggest an injury in the primary sense occurred on 9 February 2016. On this point, on the present evidence, I can go no further.
It is important to note that Ms Small has a history of symptoms that are substantially similar to those in her left thigh she attributes to the fall on 9 February 2016. On 25 March 2013, for example, Dr Pik reported –
“The leg pain is associated with sensory alteration affecting the left anterior and lateral thigh.”[108]
[108] T50 folio 219.
It is not necessary to consider the third question relating to employment to determine application 2016/3803. But that issue arises again in respect of application 2017/3099 and it is necessary to address it for that reason.
Employment
Comcare argues that liability should not have been accepted for any injuries resulting from the incident on 9 February 2016, as the incident occurred outside the protected frame of Ms Small’s employment, such that any injury in the primary sense would not have ‘arisen out of, or in the course of’ her employment for the purposes of s 5A and the deeming provision in s 6(1) of the SRC Act.
Comcare argues that the claimed injuries arose in the context of a meeting to discuss compensation and related processes, unrelated to Ms Small’s employment. Furthermore, Ms Small attended the meeting at Comcare’s request, and the meeting occurred during a break in Ms Small’s employment, and she attended at Comcare’s request.
I am not persuaded, and it was not pressed, that Ms Small’s claimed low back injury ‘arose out of’ her employment under the first limb of the deeming provision set out in s 6(1). This is because it is not presently established that her employment was causally related to Ms Small fainting, falling and hurting herself. It is not suggested that she fell because of an episode of back pain. Rather, insofar as the cause of the fall can be established on the present materials, it is probable that she experienced a vasovagal episode - she fainted. I understand that Ms Small may have some history of fainting episodes.
The second limb of the deeming provision in s 6(1) refers to ‘in the course of’ the employment. This requires a temporal rather than a causal connexion with ‘employment’.
I should say at this point that the word ‘employment’ in this context has been the subject of much consideration over time. It is not necessary to say much about the relevant authorities to which the parties drew attention in submissions. This is because the facts of this case are very clear.
The incident report that resulted from Ms Chu reporting to Ms Hofmeier is very clear on this point. Ms Small’s Duty Status is recorded as “Working at usual workplace”, without overtime or it being outside normal hours.[109]
[109] AT12 folio 38.
It was Ms Chu who conveyed Comcare’s request for a meeting to Ms Small. I do not accept that Ms Chu was a simply a conduit for communication between Comcare and Ms Small. Ms Chu’s evidence is that she had particular responsibilities as Ms Small’s AFP Rehabilitation Case Manager, and she had been briefed to some extent about Comcare’s intentions prior to the meeting. To my mind, Ms Chu encouraged Ms Small to attend the meeting, and she did so in her official capacity.
The agenda for the meeting clearly establishes that part of the purpose was to discuss rehabilitation. In that, at least, Ms Small’s employer was directly involved – Ms Chu attended the meeting as her AFP Rehabilitation Case Manager.
At this point I should observe that the AFP is the rehabilitation authority under the SRC Act, with particular responsibilities and obligations in respect of Ms Small. It was Ms Chu’s evidence that this is one important reason why she attended the meeting.
Under Part III of the SRC Act, ‘rehabilitation’ is clearly distinguished from ‘compensation’, and a ‘rehabilitation authority’ has special responsibilities in respect of assisting an injured employee to return to work or employment that may be appropriate and suitable for them.
It is for this reason that the 9 February 2016 meeting related, in part, to Ms Small’s employment, and cases relied upon by Comcare, including Australian Telecommunications Commission v Tzikas[110], Kirkpatrick v Commonwealth[111] and Prain v Comcare[112] are distinguished – each of those cases dealt with compensation proceedings outside ‘employment’. Had the 9 February 2016 meeting dealt only with compensation matters, the authorities might be on point and binding. But the 9 February 2016 meeting was expressly to deal with three matters, only two of which related to compensation. The remaining matter was rehabilitation.
[110] (1985) 5 AAR 173.
[111] (1985) 9 FCR 36.
[112] [2017] FCAFC 143.
I am not persuaded that the rehabilitation of an injured employee can be divorced for the employee’s employment in the manner for which Comcare contends.
Whether an injured employee attending a meeting to discuss compensation, rehabilitation and related matters with her rehabilitation case manager and two Comcare representatives is part of the person’s usual duties in the employment is moot – the particular terms of Ms Small’s employment by the AFP are not in evidence. That being so, I am unable to determine whether she was obligated to attend the meeting under any applicable rehabilitation or return to work provisions under the terms of her employment. No such issue was taken in Ms Small’s case, and I will go no further on that point. Nevertheless, the purposes of the rehabilitation provisions in Part III of the SRC Act include rehabilitating an injured employee into employment that is appropriate for them and obligating a rehabilitation authority, commonly the employing agency, with that responsibility.
Considering these matters and the submissions made by the parties, on balance, I am reasonably satisfied that the meeting was within the meaning of ‘in the course of’ Ms Small’s employment for the purposes of s 6(1) and 5A(1) of the SRC Act. The nexus with her employment is too close and too strong for the meeting to be taken to relate only to matters that are unrelated to her employment.
Did the injuries Ms Small sustained on 9 February 2016 resolve on or before 21 March 2017?
Comcare asserts that Ms Small’s accepted injuries from the 9 February 2016 incident resolved by 21 March 2017. Comcare relies on Dr Mourad’s evidence, in particular.
Ms Small disagrees. Her evidence is that the injuries to her left shoulder, neck, lower back and legs persist to this day, and she continues to experience headaches. Ms Small places much weight on the oral evidence of Dr Le Leu and Dr Bodel in respect of whiplash injuries.
There are some difficulties with this evidence. Principally, the difficulty is that Dr Le Leu and Dr Bodel explained that symptoms of a whiplash-type injury, such as Ms Small might have suffered when she fell, would commonly resolve within 12 months but symptoms could persist for more than two years. Well that may be in general terms, but it does not follow, and it cannot be assumed, that this is what has occurred in Ms Small’s case.
The most recent relevant evidence on this point is that of Dr Kennealy in the form of a medical certificate dated 3 October 2017.[113] The certificate is not especially helpful – it simply states that Ms Small is suffering from “c-spine neck strain, L shoulder strain, L hip and thigh soft tissue injury (contusion), aggravation of pre-existing lumbar spine injury and subsequent development of numbness in both legs (anterior left worse than right). (claim number 1076502/03)”. Treatment required is recorded to be “Analgesia (Panadeine Forte, Prozac), time off work, Review by Prof Cousin, Physio”. The doctor certified that Ms Small was fit to perform pre-injury duties from 5 October 2017 to 10 November 2017, but she was unfit for work on 3 and 4 October 2017. Dr Kennealy was not called to give oral evidence so it is not possible to clarify the contents of the medical certificate he issued.
[113] Exhibit 1.

Dr Bodel examined Ms Small on 19 April 2017. Dr Bodel reported that Ms Small “does continue to suffer with the condition of injury caused by the initial event in March 2009, the subsequent injury in May 2011 and the most recent event on 9 February 2016”.[114] Dr Bodel explained that, in his assessment, Ms Small’s injuries on 9 February 2016 were not major or structural, but rather were of a soft tissue kind that were minor and he would expect them to resolve within 12 months. Carefully considering the doctor’s evidence, I think it is clear enough that he considered Ms Small’s lumbar spine injury from 24 March 2009 to have ongoing effect, with the possibility that a whiplash-type injury to her neck occurred on 9 February 2016 when she fell to the floor, and that the effects of that injury might not yet have resolved, despite expectations to the contrary.
[114] Exhibit 3, page 13.
On 6 March 2017, Dr Martin, Ms Small’s treating general practitioner, reported that Ms Small’s “ongoing symptoms and aggravated symptoms since her injury in Feb 2016 (hedaches [sic], migraines, neck and shoulder pain, aggravated low back pain and sciatica, bilateral thigh numbness)… are still being investigated and being actively managed”.[115] The extent to which this report relates to medical certificates the doctor issued, describing incapacity for work and medical restrictions on lifting, is not especially clear. The medical certificates are not precisely worded, and it is not possible to determine whether the incapacity and restrictions imposed arise from Ms Small’s ongoing low back symptoms or to something else, perhaps in her neck or shoulder.
[115] BT27 folio 173.
As can plainly be seen in Dr Martin’s report of 28 November 2016, he considered that the contusion and sprain injuries Ms Small sustained on 9 February 2016 had significantly improved by that time, although her lower back symptoms persisted. He stated “Ms Small has had a successful recovery from her injuries listed [accepted by Comcare]”.[116] Dr Martin was not called to explain or expand upon his medical certificates or his reports.
[116] BT24 folio 168.
On balance, I am not persuaded, and the present materials do not establish, that the symptoms Ms Small reports are the continuing effect of injuries she sustained when she fell on 9 February 2016, for which Comcare accepted liability. I am not satisfied that the incapacity and medical restrictions set out in the medical certificates Dr Martin and Dr Kennealy issued are a result of those accepted injuries. Without that essential nexus being established, I cannot properly be satisfied, as a matter of probability, that the injuries caused incapacity for work or required medical treatment on and after 21 March 2017. It is possible that they did, as Ms Small asserts. But possibility is not enough.
It appears to me that Dr Martin and Dr Kennealy’s certification of incapacity and medical restrictions more probably relates to Ms Small’s ongoing low back condition and related symptoms. It is in respect of that persisting condition Ms Small obtained medical treatment from Professor Cousin.
That being so, the decision in application 2017/3099 must be affirmed.
Nevertheless, as I have said, the original injury to Ms Small’s lumbar spine involved damage to her L4/L5 disc that has persisted from then until now, despite the aggravation and probable physiological change that occurred when she fell on 18 May 2011. Absent evidence that is sufficient to separate or apportion causes of incapacity and the need for medical treatment, the incapacity that results from Ms Small’s lumbar spine injury, and the medical treatment that is reasonable for her to obtain in relation to it, continues to be compensable under s 16 and s 19 of the SRC Act.
Those matters are unaffected by affirmation of the reconsideration decision in application 2017/3099.
Decisions
The reconsideration decision in application 2016/2522 is set aside. This means the determinations revoked by that decision are reinstated. Ms Small’s 24 March 2009 low back injury is properly described as an injury to the L4/L5 disc in the form of internal disc disruption. This injury did not resolve by 24 September 2010 and it persisted as a cause of incapacity which required medical treatment on and after 18 May 2011. The events on that day probably resulted in physiological changes to the L4/L5 disc in the form of a disc protrusion, but this does not break the chain of causation between subsequent incapacity and the original 24 March 2009 injury. The matter is remitted to Comcare to determine Ms Small’s compensation entitlements under s 16 and s 19 of the SRC Act.
The reconsideration decision in application 2016/3803 is affirmed.
The reconsideration decision in application 2017/3099 is affirmed.

I certify that the preceding 208 (two hundred and eight) paragraphs are a true copy of the reasons for the decision herein of Mr S. Webb, Member

.......................................................
Associate
Dated: 24 November 2017

Date(s) of hearing: 30-31 October 2017; and 1-2 November 2017

Counsel for the Applicant: Karl Pattenden

Solicitors for the Applicant: Maurice Blackburn Lawyers

Counsel for the Respondent: Peter Woulfe

Solicitors for the Respondent: McInnes Wilson Lawyers

[2017] AATA 2383

24 November 2017

Key Legal Topics

Areas of Law

Employment Law

Administrative Law

Legal Concepts

Causation

Statutory Construction

Remedies

Expert Evidence

Procedural Fairness

Date(s) of hearing:	30-31 October 2017; and 1-2 November 2017
Counsel for the Applicant:	Karl Pattenden
Solicitors for the Applicant:	Maurice Blackburn Lawyers
Counsel for the Respondent:	Peter Woulfe
Solicitors for the Respondent:	McInnes Wilson Lawyers