Wennerbom v Dimmeys Stores Pty Ltd atf Dimmeys Unit Trust

CERTIFICATE OF DETERMINATION OF MEMBER
CITATION:	Wennerbom v Dimmeys Stores Pty Ltd atf Dimmeys Unit Trust [2023] NSWPIC 667
APPLICANT:	Irene Wennerbom
RESPONDENT:	Dimmeys Stores Pty Ltd atf Dimmeys Unit Trust
MEMBER:	Karen Garner
DATE OF DECISION:	12 December 2023
CATCHWORDS:	WORKERS COMPENSATION - Workers Compensation Act 1987; application for lump sum permanent impairment compensation pursuant to section 66; applicant had accepted injury to lumbar spine on 19 May 2010; whether the applicant sustained a consequential condition of infection in the lumbar spine and brain, which resulted in neurological impairments to station, gait, bowel and bladder, as a result the accepted injury to her lumbar spine sustained on 19 May 2010; Held – the applicant sustained a consequential condition of infection in the lumbar spine and brain, which resulted in neurological impairments to station, gait, bowel and bladder, as a result the accepted injury to her lumbar spine sustained on 19 May 2010.
DETERMINATIONS MADE:	The Commission declares: 1. The lumbar decompression surgery performed by Dr David Bell, orthopaedic surgeon, on or about 22 March 2016, was reasonably necessary as a result of the accepted injury to the applicant’s lumbar spine sustained on 19 May 2010. The Commission determines: 2. The applicant sustained a consequential condition of infection in the lumbar spine and brain, which resulted in neurological impairments to station, gait, bowel and bladder, as a result the accepted injury to her lumbar spine sustained on 19 May 2010. The Commission orders: 3. The matter is remitted to the President for referral to a Medical Assessor for assessment as follows: Date of injury: 19 May 2010 (with consequential conditions). Body parts: lumbar spine Nervous system station and gait bladder function anorectal impairment TEMSKI/scarring Method: whole person impairment. 4. The materials to be referred to the Medical Assessor are to include: (a) Application to Resolve a Dispute and attachments, and (b) Application to Admit Late Documents dated 4 October 2023 lodged by the respondent and attachments.

STATEMENT OF REASONS

BACKGROUND

Irene Wennerbom (the applicant) injured her lumbar spine lifting heavy boxes in the course of her employment with Dimmeys Stores Pty Limited atf Dimmeys Unit Trust (the respondent) on 19 May 2010.
The respondent admitted liability for the applicant’s lumbar spine injury.
The applicant underwent spinal surgery, in the form of a lumbar decompression, on 22 March 2016.
The applicant made a claim for lump sum permanent impairment compensation pursuant to s 66 of the Workers Compensation Act 1987 (the 1987 Act) for 62% whole person impairment (WPI). It was calculated on the basis of 50% impairment as a result of station and gait disorder, 15% impairment as a result of neurological anorectal impairment and 9% impairment due to bladder impairment, in accordance with assessments made by Dr Dudley O’Sullivan, consultant neurologist.
The respondent disputes liability for the claim of consequential condition.

PROCEDURE BEFORE THE PERSONAL INJURY COMMISSION

These proceedings were commenced by an Application to Resolve a Dispute (ARD) which described the injury as:
“injury to her lumbar spine... [ on 19 May 2010] which eventually required spinal surgery, in the form of a lumbar decompression, as a result of which the applicant sustained a consequential infection in her lumbar spine and brain resulting in neurological impairments to station, gait, bowel and bladder”.
The respondent lodged a Reply to the ARD (Reply) by way of an Application to Admit Late Documents (AALD).
At a conciliation conference and arbitration hearing on 22 November 2023, the applicant was represented by Mr Howard Halligan, instructed by Ms Branch of Gair Legal. The respondent was represented by Ms Nicole Compton, instructed by Ms Davis of Stacks Law Firm.
I am satisfied that the parties to the dispute understand the nature of the Application and the legal implications of any assertion made in the information supplied. I have used my best endeavours in attempting to bring the parties to the dispute to a settlement acceptable to all of them. I am satisfied that the parties have had sufficient opportunity to explore settlement and that they have been unable to reach an agreed resolution of the dispute.

ISSUES FOR DETERMINATION

The respondent accepts injury to the applicant’s lumbar spine, with a date of injury of 19 May 2010.
The parties agree that those injuries should be remitted to the President for referral to a Medical Assessor for assessment of WPI pursuant to ss 65 and 66 of the 1987 Act. The issue for determination concerns the nature and extent of such referral.
The following issues remain in dispute:
(a) whether the applicant sustained consequential infection in her lumbar spine and brain resulting in neurological impairments to station, gait, bowel and bladder, and
(b) the extent and quantification of the applicant’s entitlement to permanent impairment lump sum compensation.

EVIDENCE

Documentary evidence

The following documents were in evidence before the Personal Injury Commission (Commission) and considered in making this determination:
(a) ARD with attached documents, and
(b) AALD with attached documents.

Oral evidence

No party applied to adduce oral evidence or cross-examined any witness.

Applicant’s statement

The applicant gave evidence by way of a written statement dated 8 August 2023.
The applicant stated that she injured her lower back on 19 May 2010 in the course of performing her work duties for the respondent.
The applicant detailed a lengthy history during which she underwent various investigations, consultations and treatment in relation to ongoing pain and symptoms in her back and legs and infection in her spine and brain. The applicant stated that she consequentially suffered various ongoing impairments.

Treating medical evidence

The various treating medical evidence, which I set out below in chronological order, demonstrates a lengthy and complex medical history.
On 27 May 2010, a CT scan of the lumbar spine showed “… there is no bony canal stenosis... There is a diffuse bulge of the annulus at L4/5 with a small central disc herniation compressing the thecal sac. No other disc pathology is seen and no other nerve root compression...”.
On 27 August 2010, an MRI of the lumbar spine showed;
“... mild broadbased central and right sided disc protrusion with an associated annular tear at L4-5. … narrowing of both lateral recesses at this level with potential compromise to L5 nerve roots, particularly on the right... also a mild to moderate degree of central canal stenosis.”
On 1 September 2010, Dr Geoffrey Mutton, orthopaedic surgeon reported that the applicant was complaining of pain in her low back radiating down both her legs to her knees. Dr Mutton stated that the applicant had a small 4/L5 disc protrusion. Dr Mutton stated that there is no sign on the MRI of any lateral extension of the disc protrusion to cause nerve root compression, but the applicant did have a little spinal canal stenosis at that level, which could be causing her nerve root compression with leg pain. Dr Mutton believed that the applicant’s L4/L5 disc protrusion would heal naturally and did not require surgery.
In a report dated 20 April 2011, Dr Mutton noted that the applicant’s return to work in January 2011 was unsuccessful. Dr Mutton noted that the applicant reported back pain radiating to both legs and stated that the pathology in her L4/L5 disc was only minor and would not be expected to cause so much pain and discomfort.
On 27 May 2011, an MRI lumbar spine showed “L4/5 diffuse broadbased disc herniation with central component and facet degeneration. Very similar to previous study. No new disc herniation”
On 27 May 2011, Dr Mutton stated that an MRI “showed slight desiccation of the L4/L5 disc with a slight posterior disc bulge from a very mild posterior nuclear extrusion”. Dr Mutton did not recommend any specific treatment and hoped that it would naturally resolve. He noted that the applicant was keen to return to work and he had certified her fit to do so from 30 May 2011, initially on light duties. Dr Mutton stated that the MRI also showed “degenerative changes in L4/L5 facet joints causing some spinal canal stenosis at the L4/L5 level”, which he believed “will no doubt be slowly progressive and it is likely that … she could be a candidate for lumbar spinal decompression”.
In a report dated 2 May 2012, Dr Benjamin Jonker, neurosurgeon, stated that following the injury at work in May 2010, the applicant developed an ongoing pain syndrome with pain in her lower spine radiating down her legs. Dr Jonker noted that the applicant did not experience incontinence at that time, nor any sensory deficit. Dr Jonker noted that an MRI showed degenerative disc disease at L4/5 with an associated annular tear and mild bulge at that level, without any significant nerve compression. Dr Jonker stated that a likely cause of the applicant’s ongoing pain syndrome was discogenic disc disease. Dr Jonker recommended a trial of corticosteroid injection at L4/5 and referral to a pain management clinic.
On 25 September 2012, Dr Gibson of the Royal Prince Alfred (RPA) Hospital Pain Management Centre assessed the applicant and reported that the applicant had predominantly low back pain in the context of a significant disc injury at the L4/5 level. He noted that there is bilateral L4 neural foramen narrowing and spinal canal stenosis at that level. He recommended that the applicant undergo a combined comprehensive pain management program.
On 15 October 2012, Dr Gibson reported that the applicant’s ongoing lower limb neuropathic pain might be suitable for spinal cord stimulation, however that would not be contemplated while she remained psychologically so unstable, nor would it be indicated until less invasive therapies had proved ineffective.
On 1 July 2013, Dr Gibson reported that the applicant’s low back pain which radiated to her legs had improved after bilateral L4 paravertebral injections, however much of the benefit from these injections appeared to be reducing. Dr Gibson reported that it was appropriate to trial spinal-cord stimulation.
On 23 September 2013, Dr Yamen of the RPA Hospital Pain Management Centre reported that the applicant had recently had regular falls which necessitated presentation to the Hospital Emergency Department. Dr Yamen reported that it was hard to ascertain the cause of the falls and that she understood that serious medical pathology had been excluded as a cause for the falls and no musculoskeletal cause had been identified for the applicant’s poor balance and falls. Dr Yamen also stated that the applicant had reported one episode of urinary incontinence in the last month. Dr Yamen reported that, on examination, the applicant’s gait showed poor balance, an inability to squat to stand and inability to stand on one leg. Neurological examination of the lower limb showed normal tone, power, sensation and reflexes but showed a loss of proprioception in the applicant’s toes bilaterally, loss of vibration sense to toes on the right with preserved function at the ankle. Dr Yamen recommended the applicant undergo a repeat MRI of her lumbosacral spine, nerve conduction studies and a peripheral neuropathic screen.
On 7 November 2013, Dr Gibson reported that the applicant’s recent falls had been investigated with a lumbosacral MRI which demonstrated, “again, her known L4/5 disc bulge and moderate ligamentum flavum hypertrophy resulting in moderate canal stenosis at this level”. Dr Gibson reported that neurological examination showed some reduction in sensation in the L4 dermatome bilaterally, however there was no significant instability and no motor weakness. Dr Gibson noted some inconsistency in movement. Dr Gibson reported that, on balance, he felt that some of the applicant’s symptoms may be attributable to spinal canal stenosis and that, in that context, the applicant’s psychological condition was causing further exacerbation and reduction in her functional status. Dr Gibson recommended that the applicant be reviewed by a spinal neurosurgeon and opinions sought as to whether decompressive surgery was currently warranted.
On 6 December 2013, Dr Raoul Pope, neurosurgeon reported that the applicant had a history of lower back pain, bilateral lower limb pain and falls over a period of three and a half years. Dr Pope recorded that the applicant also has weakness in both legs with pins and needles and has used a walking stick for the last nine months, which had started after a corticosteroid injection that had been recommended by her pain specialists. Dr Pope noted that the applicant had almost immediate back spasming and leg symptoms which had not abated over the last nine months and increasing falls, recently occurring two to three times per week over the last month. Dr Pope reported that applicant had also recently experienced urinary incontinence. Dr Pope stated that the applicant did not have bowel incontinence but she experienced perineal numbness when she had severe back and leg symptoms. Dr Pope said that the applicant had a chronic pain syndrome with some elements of chronic denervation. Dr Pope recorded that the applicant walked with a stick and had a slow shuffling gait. Dr Pope stated that the applicant’s movement was limited by pain. Dr Pope stated that in his opinion the applicant “was suffering from a chronic pain syndrome and chronic denervation but lower back pain and leg pain is consistent with a stenosis, the broad based disc bulge and disc herniation may well be due to the injury in 2010 and her condition has steadily worsened”. Dr Pope stated that “Before she develops a fulminant cauda equina there is certainly symptoms that she is developing a partial cauda equina and my recommendation would be to decompress that level with an open laminectomy”. Dr Pope stated that he did:
“not feel she warrants any spinal fusion as she does not have a spondylolisthesis and there is no Modica type 2 changes and the disc space still looks relatively intact. She may be heading towards a spinal fusion in the future... The operation is not going to help with her symptoms such as her falls and also proximal symptoms and all the chronic pain syndrome but judging from the history it would be unreasonable to leave this stenosis alone”.
On 13 December 2013, Dr Pope reported that the cause of the applicant’s condition was “L4/5 disc herniation culminating in chronic pain syndrome and chronic bilateral L5 radicular pain & partial cauda equine syndrome”. Dr Pope reported that requested laminectomy/discectomy was “To prevent fulminant cauda equina syndrome (permanent bladder/bowel/sexual dysfunction). Help with leg pain & back pain”. Dr Pope reported that the cause of the applicant’s falls was “Disuse syndrome. Disc herniation Chronic denervation Chronic pain syndrome”. Dr Pope reported that the requested procedure would “help to rebuild her core strength, mobility and indirectly will help reduce falls”. Dr Pope reported that “The chronic pain syndrome & chronic denervation & disuse syndrome will impact negatively. However delaying surgery with partial cauda equina symptoms is not recommended”. Dr Pope stated that fusion surgery may be required in the future.
On 9 December 2014, nerve conduction tests showed “findings in relation to the right common peroneal and posterior tibial F wave conduction studies were consistent with a right LS/S1 radiculopathy … The findings in relation to the left posterior tibial F wave conduction study to AH was consistent with a left SI radiculopathy”. There was no electrical evidence of a generalised peripheral sensorimotor neuropathy or of focal pathology affecting any of the nerves tested in the limbs.
On 13 July 2015, a CT scan showed “severe canal stenosis at L4/5 with almost complete obliteration of the thecal sac. This is secondary to posterior broadbased disc prolapse, with ligamentum flavum hypertrophy and grade I spondylolisthesis”.
On 15 July 2015, Dr Whitmill, general practitioner, reported that the applicant “is having increasing significant problems with her back and falls. As can be seen her CT scan has significant problems with L4/5 and NEEDS AN OPERATION URGENTLY“.
On 29 July 2015, Dr David Bell, spinal surgeon, reported that the applicant had longstanding issues with low back and leg pain. Dr Bell stated that the applicant:
“saw Dr Pope in 2013 who felt that she needed an L4/5 decompression of her stenosis. I agreed with his assessment back then. Irene’s main complaint now is of pain in her left leg. It radiates down the outside of her leg to the ankle. She has also had multiple falls. Her bladder and bowel function are currently normal. On examination, she walks with an antalgic gait on the left. Lower limb neurological examination reveals Grade 4 power of extensor hallucis longus bilaterally. She has present and symmetrical ankle and knee jerks. An MRI of her lumbosacral spine in 2013 shows fairly severe canal stenosis at L4/5”.
Dr Bell stated that he believed that the applicant’s “leg pain is undoubtedly due to the L 4/5 stenosis, I think she will need an L 4/5 decompression to address this”.
On 26 August 2015, Dr Bell reported that the applicant’s latest MRI “confirms that she has fairly severe stenosis at the L4/5 level. I think this definitely accounts for the pain down the outside of her leg”. Dr Bell stated that the applicant “would benefit from an L4/5 decompression. I have advised her that this should help with the pain in her left leg”.
On 17 September 2015, the applicant was treated at Manning Base Hospital Emergency Department for severe exacerbation of back pain after long drive.
On 27 February 2016, the applicant collapsed and was treated at Parkes District Hospital.
On 10 March 2016, Dr Bell reported that the applicant’s physiotherapist stated that her “symptoms have worsened significantly. It sounds as though over the last few months she has had intermittent problems with urine incontinence as well” and Dr Bell recommended that surgery was expedited.
On 22 March 2016, the applicant underwent an L4/5 laminectomy and decompression of the left L5 nerve root, performed by Dr Bell at the Orange Base Hospital.
On 10 May 2016, Dr Bell reported that, six weeks following L4/5 decompression for left leg sciatica, the applicant’s left leg pain had completely gone however the applicant reported right leg pain which was ongoing since it commenced two weeks after the surgery. Dr Bell was unsure of the cause of the applicant’s right leg pain.
On 6 July 2016, Dr Bell reported that “we may need to plan surgery again for her right leg pain”.
On 20 July 2016, Dr Bell reported that the applicant was “still complaining of right leg sciatica. She does have some lateral recess stenosis on the right. Her left leg is great. Given that it is not settling, I think the only option is to go in and decompress the L5 nerve root on the right hand side”.
On 8 December 2016, Dr Ian Thong, pain management specialist reported that the applicant had “neuropathic leg pain due to a L4/5 disc protrusion. The left Iaminectomy provided relief but now has right leg neuropathic leg pain. Dr Bell is planning to re-operate? right Iaminectomy/microdiscectomy or (? fusion)”.
On 11 January 2017, Dr Thong stated that the applicant’s pain was upsetting and she reported not being able to leave the house since before Christmas. Dr Thong reported that the applicant had tried various medications.
On 21 January 2017, the applicant was taken by ambulance to Parkes District Hospital Emergency Department with a presenting problem of “Chronic Back Pain”. Records noted that the applicant:
“states discharge from Parkes Hospital yesterday evening after Rx for back problems. Today pt has frequent bowel motions with blood and clots in them. States has had nothing solid for three days. O/E pt alert, oriented and well perfused. Pt c/o lower back pain. States occasional lower abdominal pain. Pt very poor mobility…”

On 22 January 2017, the applicant received inpatient treatment at Parkes District Hospital for chronic back pain.
On 24 January 2017, Dr Bell reported that the applicant looked “incredibly unwell” and was very pale and shaky and that he referred her to the Emergency Department for investigation.
On 24 January 2017, an MRI lumbar spine showed a right sided posterior-spinal muscle abscess.
Between 24 January and 1 February 2017, the applicant received inpatient treatment at the Orange Base Hospital. On 24 January 2017, an MRI lumbar spine showed a right sided posterior-spinal muscle abscess and fluid from a CT-guided drain demonstrated methicillin-susceptible Staphylococcus aureus bacteria infection. The applicant was admitted to the intensive care unit. A Discharge Summary of the Orange Hospital dated 1 February 2017 stated that the MRI brain and spine were reported and reviewed on several occasions by radiologists, neurologists and neurosurgeons but after review by Dr Liz Thompson, was ultimately reported as a subdural empyema (right frontal and around cerebellum) and ventriculitis on 1 February 2017. The Discharge Summary stated that an MRI:
“showed right posterior spinal musculature abscess likely due to a right L4/5 facet joint septic arthritis measuring 25mm x 28mm x 24mm and involvement of the Left L4/5 facet joint. Although there was some epidural enhancement at this and the adjacent levels, there was no significant epidural abscess.”
The applicant continued to receive inpatient hospital treatment for infection in various hospitals for until late March 2017.
On 3 February 2017, Dr Kaitlyn Parratt, neurologist, reported “evidence of a moderate to severe diffuse encephalopathy”.
On 6 February 2017, an MRI Brain and Whole Spine showed:
“There is an insinuating epidural abscess which extends from T10-S1. Within the surgical bed at the L4 laminectomy site, there are bilateral L4-5 facet joint effusions (more on the right than the left) and locules of collection as described above. There is likely right L4/5 facet septic arthritis. Evaluation of the underlying cord is limited due to significant motion artefact. There is crowding of the cauda equina and no definite cord oedema demonstrated. Within the partly visualised posterior fossa, the presence of cerebellar extra-dural abscesses are noted”.
On 27 February 2017, the RPA records stated a principal diagnosis of “multiple spinal abscesses and brain empyemas”.
On 26 April 2017, a CT Brain and Lumbar Spine showed:
“CT Brain: ... Subdural collections seen previously on the MRI of 09/03/2017 are not visualised...CT Lumbar spine: … There is mild anterior spondylolisthesis of L4 upon L5. At this level, there is a broad-based disc-osteophyte complex herniation resulting in severe central canal stenosis”.
On 13 May 2017, an MRI Lumbar Spine showed:
“articular surface destruction involving both facet joints consistent with the history of septic arthritis and the diffuse enhancement does raise the possibility of active infection / inflammation. There is also a prominent epidural enhancement with some distortion of the thecal sac. The degree of thecal sac compression is slightly more marked than on the previous MRI”.
On 16 May 2017, Dr Bell, reported that:
“In late January she was found to have septic arthritis of the facet joints at L4/5, twelve months following her lumbar decompression. Unfortunately this spread to her brain in the form of meningitis. She spent about nine weeks in RPA on antibiotics... Irene’s main complaint now is of back pain and fairly severe pain in her right leg. The recent MRI shows some stenosis at the L4/5 level, and evidence of the recent facet joint arthritis”.
On 23 August 2017, an MRI Brain and Whole Spine (reported on 31 August 2017) showed:
“Resolution of previously demonstrated intracranial posterior fossa collections and right subfrontal focus of enhancement. Reducing enhancement within the bifrontal regions of encephalomalacia change. …. less pronounced smooth epidural enhancement within the spine, as well as reduction in the soft tissue fluid enhancement surrounding the L4/5 facet joints... There is an equivocal slight increase in enhancement within the epidural space posterior to L4 and L5 vertebral bodies although there is no appreciable fluid collection”.
On 25 October 2017, Dr Bell reported that “CRP is essentially unchanged, but her ESR is heading in the right direction. Her predominant complaint is back pain but she does get some pain in her right leg”.
On 14 February 2018, Dr Bell reported that he would trial the applicant off antibiotics.
On 12 April 2018, Dr Whitmill, general practitioner, recorded that the applicant had recently been extremely confused and had memory difficulties.
On 9 May 2018, Dr Bell reported that the applicant’s “latest CRP is 48. This has risen somewhat from 35 ... She has no headaches, no fevers and still has her appetite. … Irene is certainly a complex case, and we don’t seem to be winning quite yet”.
On 10 May 2018, Dr Whitmill recorded that the applicant had bilateral back pain with referred leg pain.
On 30 July 2018, Dr Whitmill recorded that the applicant was receiving ongoing treatment under her orthopaedic surgeon.
On 29 November 2018, Dr Bell reported that the applicant continued to have elevated C-reactive protein level (CRP) of 34.
On 19 December 2018, Dr Bell reported that the applicant had been feeling well after ceasing antibiotics but continued to have elevated CRP of 34. Dr Bell stated that it was possible that she still had some residual underlying infection or some other inflammatory issue. Dr Bell stated that the “infection in the brain appears to have cleared and there is certainly no evidence of residual infection in her lower spine”.
On 1 September 2020, Dr Whitmill recorded that since the infection, the applicant’s processing of facts and grasp on what has been done has been affected and her activities of daily living were reportedly reduced.
In a report dated 23 August 2022, Dr David Bell, treating orthopaedic surgeon, stated that the applicant sustained an annular tear of the L4/5 disc, which was consistent with being sustained during a lifting injury. Dr Bell stated that the annular tear predisposed the applicant to a disc herniation on the left hand side at L4/5 and was the major contributor to the applicant’s left leg sciatica. Dr Bell stated that the laminectomy was reasonably necessary to treat the underlying pathology causing the applicant’s left leg sciatica. Dr Bell stated that laminectomy is a well-established operation for the treatment of sciatica due to neural compression. Dr Bell stated that in his opinion the predominant cause of the applicant’s symptoms was the disc herniation, which likely resulted from her work injury in 2010, and as a result, the laminectomy was reasonably necessary to treat the applicant’s injury sustained at work. Dr Bell stated that the MRI lumbar spine conducted on 26 August 2010 concluded that the applicant had mild-to-moderate central canal stenosis, which would suggest that any pre-existing spinal canal stenosis was not significant. Dr Bell stated that a repeat MRI lumbar spine conducted on 6 August 2015 concluded that the applicant then had high-grade central canal stenosis. Dr Bell stated that the predominant difference appears to be the disc herniation. On that basis, Dr Bell considered that it is reasonable to conclude that any pre-existing spinal stenosis was not significant, and the difference in the degree of spinal stenosis from 2010 to 2015 was caused by the disc herniation which likely resulted from the applicant’s work injury.

Independent medical evidence

Dr O’Keefe, orthopaedic surgeon

Dr O’Keefe provided an independent medical opinion, qualified by the respondent.
In a report dated 25 January 2012, Dr O’Keefe expressed the opinion that the applicant’s back injury was minor and non-neurologically compressive and that surgery was not indicated. Dr O’Keefe stated that examination did not show anything to suggest a symptomatic lumbar disc lesion. Dr O’Keefe acknowledged that the applicant had an annular tear and some minor disc pathology at L4/5, which probably was a result of the applicant’s work injury. Dr O’Keefe stated that although the annular tear can cause back pain, the pathology was only minor and could not possibly cause the symptoms that the applicant was suffering. Dr O’Keefe stated that there were marked inconsistencies in the applicant’s clinical examination and the ongoing symptoms were affected by an overlay of psychological issues. Dr O’Keefe stated that the applicant’s work was the substantial contributing factor to her back injury and she had pre-existing degenerative changes. Dr O’Keefe assessed total 5% WPI, calculated on the basis of 5% WPI for lumbar spine and 1% for alteration of activities of daily living.

Dr Raymond Wallace, orthopaedic surgeon

Dr Wallace provided an independent medical opinion.
In reports dated 9 March 2012, Dr Wallace stated a diagnosis of musculoligamentous strain, lumbar spine, disc protrusion at the L4/5 level and temporary aggravation of pre-existing degenerative disc disease of the lumbar spine. Dr Wallace stated that the applicant’s lumbar spinal condition was caused by her work injury of May 2010, with a proportion being due to pre-existing degenerative disc disease at the lumbar spine. Dr Wallace stated that the aggravation of the applicant’s pre-existing degenerative disc disease had resolved. Dr Wallace stated that the applicant did nor require operative intervention. He recommended that she undergo a home exercise program with intermittent use of analgesic and anti-inflammatory medication. Dr Wallace assessed total 6% WPI, calculated on the basis of a 7% WPI for lumbar spine and a deduction due to pre-existing degenerative disc disease at her lumbar spine.

Dr Vidyasagar Casikar

Dr Casikar provided an independent medical opinion, qualified by the respondent.
In a report dated 23 December 2013, Dr Casikar stated a diagnosis of a work-related aggravation of a pre-existing L4 constitutional degenerative disease of the lumbar spine. Dr Casikar agreed with the opinion of Dr Wallace that the work related temporary aggravation had then resolved.
Dr Casikar stated that the applicant’s neurological symptoms were non-verifiable. Dr Casikar stated that the L4/L5 stenosis does not explain the applicant’s non-verifiable symptoms of perianal anaesthesia and hypoesthesia bilaterally from groin down both legs. Dr Casikar stated that he did not believe that the applicant’s falls were a neurological problem. Dr Casikar stated that significant emotional issues needed further evaluation and an assessment of their interrelationship with her physical symptoms.
Dr Casikar did not believe that the applicant required any further treatment or investigations. However, Dr Casikar stated that the decompression of L4/5 segment, laminectomy suggested by Dr Pope, was a reasonable procedure to address issues related to the applicant’s severe lumbar canal stenosis. He stated that such surgery was not necessary as a consequence of the applicant’s work injury. Dr Casika recommended that the applicant’s emotional issues were addressed before surgery was considered.
Dr Casika noted that Dr Pope indicated that the applicant was developing cauda equina syndrome based on her complaint that she was experiencing urinary incontinence. However, Dr Casikar stated that his clinical examination of the applicant and available evidence including surveillance reports did not indicate cauda equina syndrome.
In a supplementary report dated 17 February 2014, Dr Casikar stated that he did not believe that the facet injections would produce the urinary incontinence and perianal numbness reported by the applicant. Dr Casikar could not detect any neurological reasons to explain the applicant’s constant collapsing and he considered that her reported symptoms were not verifiable. Dr Casikar suggested that psychiatric problems may be the main reason for the applicant’s non-verifiable neurological problems. Dr Casikar questioned the applicant’s failure to indicate her previous psychiatric history.

Dr Grant Walker, consultant neurologist

Dr Walker provided an independent medical opinion, qualified by the respondent.
In a report dated 24 February 2022, Dr Walker noted that the applicant reported constant lower back pain which radiated diffusely into both legs, numbness of her legs from the thighs down to her feet and including the perineal regions. Dr Walker noted that the applicant reported a degree of urinary incontinence but did not complain of anorectal problems. He noted that she walked using a stick for support and had a wide based gait and could not attempt tandem gait.
Dr Walker diagnosed a soft tissue injury of the lumbar spine. Dr Walker accepted that there was a workplace injury in 2010, the effects of which would have resolved had there not been ongoing and pre-existing lumbar canal stenosis.
Dr Walker stated that the applicant’s current physical condition relates to her lumbar canal stenosis and the catastrophic infection suffered as a result of surgery for the lumbar canal stenosis. Dr Walker stated that the worsening lumbar canal stenosis, subsequent surgery, and resulting infection are not related to the applicant’s employment in 2010.
Dr Walker agreed that the applicant’s WPI should be assessed using a rating for “station and gait disorders” and bladder impairment, however he did not find any anorectal abnormalities. Dr Walker assessed total 44% WPI, which he calculated on the basis of 39% WPI for station and gait disorders and 9% for bladder impairment. Dr Walker stated that the impairment relates mostly to the spinal and brain infection that the applicant suffered. He stated that the original accident caused some lower back pain with non-specific symptoms in the legs which equates to 5% WPI in respect of the lumbar spine.

Dr Dudley O’Sullivan, consultant neurologist

Dr O’Sullivan provided an independent medical opinion, qualified by the applicant.
In a report dated 2 November 2021, Dr O’Sullivan stated that the applicant reported: an increase in the severity of her back pain over the last four years, with pain going down both buttocks and legs, anteriorly and posteriorly to her feet, which feel numb; frequent falls as a result of her persistent pain in her back and legs; problems with bladder and bowel control; and no sensation with bladder and bowel. On examination, Dr O’Sullivan noted that the applicant had somewhat reduced movement, reflexes and sensory responses. Dr O’Sullivan noted that the applicant’s gait was abnormal, and she walked with a stick and was unable to stand on her heels or toes.
Dr O’Sullivan diagnosed a herniated disc protrusion at L4/5 requiring surgical decompression and subsequently complicated by the presence of initially an abscess in the paraspinal muscular region, which required drainage and subsequently it developed into an osteomyelitis of the facet joint resulting in epidural abscess together with haematological spread producing subdural empyema intracranially. Dr O’Sullivan stated that resulted in the applicant developing a cauda equina lesion.
Dr O’Sullivan expressed his opinion that the spinal infection at the level of the L4/5 laminectomy and decompressive surgery was a consequential injury as a result of the applicant having had the surgery. Dr O’Sullivan noted that the infection was at the site of the surgical procedure. Dr O’Sullivan concluded that the entire symptomatology in relating to the applicant’s spinal abscess and subdural empyema are related to the applicant’s original injury to her spine and subsequent surgical procedure.
Using the SIRA Guidelines, Fourth Edition, March 2021 (SIRA Guidelines) and AMA Guides to the Evaluation of Permanent Impairment, Fifth Edition (AMA Guides) Dr O’Sullivan assessed 62% total WPI, which he calculated on the basis of 50% impairment as a result of station and gait disorder, 15% as a result of neurological anorectal impairment and 9% due to bladder impairment.
In a supplementary report dated 13 September 2022, Dr O’Sullivan reported that he disagreed with Dr Walker’s opinion that the worsening of the applicant’s lumbar canal stenosis, subsequent surgery and resultant infection were related to her employment in 2010. Dr O’Sullivan stated that, from his history and assessment, there was no pre-existing evidence that the applicant had significant pre-existing lumbar canal stenosis prior to the events that occurred in May 2010.
Dr O’Sullivan further reported that he agreed with the conclusion of Dr Bell that the laminectomy surgery was reasonably necessary to treat the underlying pathology causing the sciatica in the applicant’s left leg, which was a result of the back injury sustained at work on 19 May 2010. Dr O’Sullivan agreed with Dr Bell’s opinion that the predominant cause of the applicant’s sciatica symptoms was stenosis at the L4/5 level, which was particularly contributed to on the left side by a disc herniation, being an annular tear of the L4/5 disc sustained during a lifting injury at work, on a background of underlying degenerative changes. On that basis, Dr O’Sullivan maintained his previous WPI assessment.

SUBMISSIONS

Applicant’s submissions

In summary, the applicant’s submissions were that:
(a)    the applicant’s evidence in relation to the circumstances of her injury and her impairments should be accepted;
(b)    Dr O’Sullivan’s evidence should be preferred and accepted;
(c)    the Commission should find on the applicant’s evidence and the medical evidence that the spine surgery was reasonably necessary as a result of the accepted work injury;
(d)    the applicant’s evidence in relation to her impairments to station, gait, bowel and bladder are supported by Dr O’Sullivan’s evidence and should be accepted;
(e)    the Commission should find on the applicant’s evidence and the medical evidence that the applicant’s current impairments result from the surgery;
(f)    there is no evidence of an alternate mechanism of injury, and
(g)    accordingly, the Commission should find for the applicant.

Respondent’s submissions

In summary, the respondent’s submissions were that:
(a)    the respondent accepts that the applicant injured her lumbar spine in the accepted work injury;
(b)    Dr O’Sullivan’s opinion is not based on a correct history because it was not based on the correct reason for the spinal surgery. Further, Dr O’Sullivan’s opinion is not supported by other medical evidence and should not be accepted;
(c)    the medical evidence does not establish that the spine surgery was reasonably necessary as a result of the accepted work injury. The medical evidence demonstrates that the surgery was the result of the applicant’s pre-existing L4/5 stenosis and not the disc bulge;
(d)    the applicant has not satisfied the onus of proof and the Commission should not accept on the applicant’s evidence and the medical evidence that the applicant has the alleged impairments to station, gait, bowel and bladder;
(e)    there are gaps in the medical evidence and the medical evidence does not establish sufficient causal nexus between the deterioration of the applicant’s condition and the accepted work injury or the surgery. Any apparent chain of causation between the accepted work injury and the alleged impairments, was broken by intervening acts which exacerbated the applicant’s condition and broke any apparent chain of causation. These include: significant and unexplained deterioration of the applicant’s condition after it had somewhat resolved by about 2012; medical evidence supports a finding that the applicant’s ongoing symptoms were due to overlying psychological issues; the applicant’s regular falls which the medical evidence shows were unexplained and not identified as the result of the accepted work injury or the surgery; the applicant underwent corticosteroid injection. In particular, the applicant has not pleaded that she sustained a cauda equina lesion and in any event the medical evidence does not establish any radiological evidence of a cauda equina lesion which was a result of the accepted work injury or the surgery. Further, the existence of any causal nexus between the alleged impairments and the surgery, as alleged by the applicant, is inconsistent with the existence of certain impairments prior to the surgery, and
(f)    accordingly, the Commission should find for the respondent.

Applicant’s submissions in reply

In summary, the applicant’s submissions in reply were that:
(a)    the respondent has not given evidence by a qualified psychiatrist. The principles in Browne v Dunn (1893) 6 R 67 apply and the respondent has not put the substance any contradictory evidence to the applicant regarding any psychological cause of the applicant’s condition;
(b)    medical evidence supports a finding that the applicant’s episodes of falling were related to her lumbar spinal problem. In particular, a fall risk screening emanated from the applicant being hospitalised with a lumbar spinal problem;
(c)    medical evidence supports a finding that the applicant had faecal incontinence associated with her spinal condition;
(d)    there is no evidence that the applicant had any significant pre-existing lumbar spine symptomatology or condition prior to the L4/5 injury, and
(e)    on that basis, the Commission should find for the applicant.

FINDINGS AND REASONS

The law

It is not necessary for the applicant to establish that a consequential condition is itself an ‘injury’ pursuant to s 4 of the 1987 Act nor that the employment was a substantial contributing factor within the meaning of s 9A of the 1987 Act. In Moon v Conmah Pty Ltd,[1] Deputy President Roche stated at [45]-[46]:[2]
“It is therefore not necessary for Mr Moon to establish that he suffered an ‘injury’ to his left shoulder within the meaning of that term in section 4 of the 1987 Act. All he has to establish is that the symptoms and restrictions in his left shoulder have resulted from his right shoulder injury. Therefore, to the extent that the Arbitrator and Dr Huntsdale approached the matter on the basis that Mr Moon had to establish that he sustained an ‘injury’ to his left shoulder in the course of his employment with Conmah they asked the wrong question.”
[1] [2009] NSWWCCPD 134.
[2] See also Kumar v Royal Comfort Bedding Pty Ltd [2012] NSWWCCPD 8, at [61].
In Bouchmouni v Bakhos Matta t/as Western Red Services,[3] Deputy President Roche stated:
“The Commission has considered and explained the difference between an ‘injury’ and a condition that has resulted from an injury in several recent decisions…
The injury to Mr Bouchmouni’s right knee caused him to seek treatment in the form of surgery and physiotherapy. The evidence suggests that it was in the course of receiving that treatment, and/or as a result of an altered gait because of his knee symptoms, Mr Bouchmouni developed back symptoms. If that is accepted, and no reason has been advanced why it should not be, it is clear beyond doubt that his back condition has resulted from the treatment he received for his accepted knee injury and his altered gait. That does not, however, make the back condition an ‘injury’.”
[3] [2013] NSWWCCPD 4.
The applicable legal test of causation was set out by the Court of Appeal in Kooragang,[4] where Kirby P (as his Honour then was) stated:
“From the earliest days of compensation legislation, it has been recognised that causation is not always direct and immediate…
Since that time, it has been well recognised in this jurisdiction that an injury can set in train a series of events. If the chain is unbroken and provides the relevant causative explanation of the incapacity or death from which the claim comes, it will be open to the Compensation Court to award compensation under the Act.”[5]
[4] (1994) 35 NSWLR 452; 10 NSWCCR 796.
[5] Kooragang, at [461] (Sheller and Powell JJA agreeing).
His Honour stated at [463]-[464]:
“The result of the cases is that each case where causation is in issue in a workers’ compensation claim, must be determined on its own facts. Whether death or incapacity results from a relevant work injury is a question of fact. The importation of notions of proximate cause by the use of the phrase ‘results from’, is not now accepted. By the same token, the mere proof that certain events occurred which predisposed a worker to subsequent injury or death, will not, of itself, be sufficient to establish that such incapacity or death ‘results from’ a work injury. What is required is a commonsense evaluation of the causal chain. As the early cases demonstrate, the mere passage of time between a work incident and subsequent incapacity or death, is not determinative of the entitlement to compensation. In each case, the question whether the incapacity or death ‘results from’ the impugned work injury (or in the event of a disease, the relevant aggravation of the disease), is a question of fact to be determined on the basis of the evidence, including, where applicable, expert opinions. Applying the second principle which Hart and Honoré identify, a point will sometimes be reached where the link in the chain of causation becomes so attenuated that, for legal purposes, it will be held that the causative connection has been snapped. This may be explained in terms of the happening of a novus actus. Or it may be explained in terms of want of sufficient connection. But in each case, the judge deciding the matter, will do well to return, as McHugh JA advised, to the statutory formula and to ask the question whether the disputed incapacity or death ‘resulted from’ the work injury which is impugned.”
Although the High Court in Comcare v Martin[6] raised some concerns about the common sense evaluation of the causal chain in a matter that concerned Commonwealth legislation, the common sense approach still has place in the application of the legislation to the present case.
[6] [2016] HCA 43, at [42].
The Court of Appeal in Nguyen v Cosmopolitan Homes[7] held that a tribunal of fact must be actually persuaded of the occurrence or existence of the fact before it can be found, and stated:
“(1)    A finding that a fact exists (or existed) requires that the evidence induce, in the mind of the fact-finder, an actual persuasion that the fact does (or at the relevant time did) exist;
(2)     Where on the whole of the evidence such a feeling of actual persuasion is induced, so that the fact-finder finds that the probabilities of the fact’s existence are greater than the possibilities of its non-existence, the burden of proof on the balance of probabilities may be satisfied;
(3)     Where circumstantial evidence is relied upon, it is not in general necessary that all reasonably hypotheses consistent with the non-existence of a fact, or inconsistent with its existence, be excluded before the fact can be found, and
(4)     A rational choice between competing hypotheses, informed by a sense of actual persuasion in favour of the choice made, will support a finding, on the balance of probabilities, as to the existence of the fact in issue.”
[7] [2008] NSWC 246.
The applicant bears the onus of proof.

Consideration

The applicant’s lumbar spine injury on 19 May 2010 is accepted.
The applicant’s credibility has not been challenged and she was not cross-examined.
The factual matters set out in the applicant’s statement are not in dispute, with the exception that the respondent denies the existence of the alleged impairments to station, gait, bowel and bladder.
The applicant’s evidence in relation to the circumstances of the injury on 19 May 2010 and the subsequent medical history is largely consistent with the treating medical evidence and the history recorded by the independent medical evidence.
The medical evidence set out above, which I accept, demonstrates a lengthy and complex medical history following the lumbar spine injury on 19 May 2010.
There is no evidence that the applicant had any significant pre-existing lumbar spine symptomatology or condition prior to the accepted lumbar spine injury.
I accept that the medical evidence before me is not the entire and complete extent of the applicant’s medical history. However, I note that the respondent did not seek directions for production of any further medical evidence to address any alleged inadequacy in that regard.
The medical evidence before me is, nevertheless, substantial. I am satisfied that it substantially addresses the applicant’s injury, symptoms and medical history over a relevant and lengthy period of time.
The initial CT scan of the lumbar spine on 27 May 2010, performed shortly after the accepted lumbar spine injury, showed diffuse bulge of the annulus at L4/5 with a small central disc herniation compressing the thecal sac. Subsequent imaging, including in August 2010 and May 2011, also showed similar evidence of disc protrusion at L4/5 level with an associated annular tear.
The initial CT scan of the lumbar spine on 27 May 2010, performed shortly after the accepted lumbar spine injury, showed no bony canal stenosis nor other disc pathology and no nerve root compression. However, various subsequent imaging from August 2010 showed evidence of progressing degenerative disc disease at L4/5: a “little” spinal canal stenosis at the L4/5 level was seen on imaging in August 2010 which Dr Mutton stated could be causing nerve root compression with leg pain (as noted by Dr Geoffrey Mutton in his report dated 1 September 2010), which apparently progressed to a “moderate” amount in November 2013 (as noted by Dr Gibson in his report dated 7 November 2013) and a “severe” amount in July 2015 (as noted by Dr Bell in his report dated 29 July 2015).
Various medical evidence shows that, at numerous times subsequent to the accepted lumbar spine injury, the applicant reported lumbar spine pain which radiated into both legs.
It is apparent on the evidence that Dr Mutton considered that the applicant’s symptoms resolved to the extent that he certified her fit and the applicant attempted to return to work in January 2011 and again in May 2011, subject to certain restrictions. Dr Mutton’s report dated 27 May 2011 indicates that the applicant was keen to return to work and he was hopeful that the applicant’s disc bulge would naturally resolve. However, it is also apparent from the evidence, and I accept, that the applicant’s attempted return to work was ultimately unsuccessful, at least in part, due to her ongoing pain condition.
In 2012, Dr Jonker, neurosurgeon, recommended a trial of corticosteroid injection at L4/5 and referral to a pain management clinic.
Considering the medical evidence as a whole, I am not satisfied that the applicant’s symptoms did resolve significantly, before significantly deteriorating in a manner which cannot be explained or which is explained by intervening factors other than her accepted injury. It is apparent from the medical evidence, and I accept, that the applicant’s pain condition progressed and she experienced significant ongoing back and leg pain.
Various medical evidence records, and I accept, that applicant also experienced regular episodes of falling.
In June 2013, Dr Pope reported that the applicant then experienced pain with pins and needles, had problems with her gait, used a walking stick and experienced recent falls and experienced perineal numbness and urinary incontinence following a corticosteroid injection.
In September 2013, Dr Yamen of the RPA Hospital Pain Management Centre reported that the applicant had recently had regular falls and that the applicant had issues with her gait and ability to balance. Dr Yamen noted that the cause of the falls had not been ascertained. In 2015 and early 2016, Dr Whitmill and Dr Bell also recorded that the applicant had experienced multiple falls. Whilst the treating medical evidence does not specifically state a causal relationship between the falls and the accepted injury, it appears to me to be implicit in the reports of Dr Whitmill dated 15 July 2015 and Dr Bell of 29 July 2015 that they considered that the falls were causally related to the applicant’s severe pain. I note that there is no evidence of any other explicit cause of the applicant’s regular falls.
In September 2013, Dr Yamen noted that the applicant had recently experienced one episode of urinary incontinence. In his report dated 10 March 2016, Dr Bell reported that the applicant was then also experiencing urinary incontinence.
Turning to the issue of causation, in January 2012, Dr O’Keefe, orthopaedic surgeon, acknowledged that the applicant had an annular tear and some minor disc pathology, which was probably a result of the applicant’s work injury, with some pre-existing degenerative changes. Dr O’Keefe accepted that the annular tear can cause disc pain but he considered that the applicant’s pain was not fully explained by the pathology which he considered to be relatively minor. Accordingly, Dr O’Keefe did not consider that surgery was indicated.
In March 2012, Dr Wallace, orthopaedic surgeon, stated a diagnosis of musculoligamentous strain of the lumbar spine, disc protrusion at the L4/5 level and temporary aggravation of pre-existing degenerative disc disease of the lumbar spine. Dr Wallace expressed the opinion that the applicant’s lumbar spine condition was caused by her accepted work injury in 2010, with a proportion due to pre-existing degenerative disc disease at the lumbar spine. Dr Wallace stated that surgical intervention was not required.
In his report dated 7 November 2013, Dr Gibson stated that a lumbosacral MRI demonstrated “again, her known L4/5 disc bulge and moderate ligamentum flavum hypertrophy resulting in moderate canal stenosis at this level”. Dr Gibson accepted, on balance, that some of the applicant’s symptoms may be attributable to spinal stenosis but he considered that it may also be impacted by a psychological condition.
It is also apparent from the treating medical evidence, and I accept, that the applicant underwent various treatments to address her back and leg pain, including a trial of corticosteroid injection at L4/5 and referral to a pain management clinic, however they did not provide any significant enduring relief.
In his report dated 6 December 2013, Dr Pope noted a temporal connection between the applicant’s pain and other symptoms and the corticosteroid injection, however Dr Pope did not express any causal relationship between them. To the contrary, Dr Pope stated that the applicant’s pain was consistent with a stenosis, disc bulge and disc herniation which he considered may be caused by the applicant’s accepted work injury in 2010 which had steadily worsened. Further, in his report dated 13 December 2013, Dr Pope reported that the cause of the applicant’s condition was L4/5 disc herniation culminating in chronic pain syndrome and chronic bilateral L5 radicular pain and partial cauda equina syndrome.
In December 2013, Dr Casikar provided an independent medical opinion and stated a diagnosis of a work-related aggravation of a pre-existing L4 constitutional degenerative disease of the lumbar spine, however he was of the opinion that the work-related temporary aggravation had then resolved. On that basis, although he accepted that surgery was a reasonable procedure to address issues related to the applicant’s severe lumbar canal stenosis, he stated that such surgery was not necessary as a consequence of the applicant’s work injury. In a report dated 17 February 2014, Dr Casikar was unable provide a neurological explanation for the applicant’s reported falls, urinary incontinence and perianal numbness however he rejected the proposition that the injection would cause the applicant’s symptoms.
Whilst various medical evidence raised the suggestion that the applicant’s ongoing pain may have been causally connected to overlying psychological issues, that is not supported by any qualified psychiatric opinion. On that basis, I am not satisfied that there is any definitive nor likely psychiatric diagnosis which is the cause of the applicant’s symptoms.
On 13 July 2015, a CT scan showed severe canal stenosis at L4/5 “secondary to posterior broadbased disc prolapse, with ligamentum flavum hypertrophy and grade 1 spondylolisthesis”.
Both the applicant’s treating orthopaedic surgeon, Dr Bell, and treating general practitioner, Dr Whitmill, recommended L4/5 laminectomy and decompression surgery to address the applicant’s pain.
In his report dated 29 July 2015, Dr Bell, stated that he believed that the applicant’s leg pain was due to severe stenosis at the L4/5 level. In a later report dated 23 August 2022, Dr Bell provided a more detailed explanation of his opinion regarding causation of the applicant’s symptoms. Dr Bell stated that the applicant sustained an annular tear of the L4/5 disc, which was consistent with a lifting injury, and which predisposed the applicant to a dis herniation of the left hand side at L4/5 and was the major contributor to the applicant’s leg pain. Having regard to the changes to the applicant’s lumbar spine shown by various imaging since the applicant’s work injury. Dr Bell expressed the opinion that any pre-existing canal stenosis was not significant, and that the difference in the degree of spinal stenosis from 2010 to 2015 was caused by the disc herniation, which likely resulted from the applicant’s work injury.
The independent medical expert qualified by the respondent, Dr Walker, expressed the opinion that the effects of the applicant’s accepted work injury in 2010 would have resolved had there not been pre-existing and ongoing lumbar canal stenosis. On that basis, Dr Walker was of the opinion that the applicant’s worsening lumbar canal stenosis and subsequent surgery were not related to the applicant’s accepted work injury in 2010.
The independent medical expert qualified by the applicant, Dr O’Sullivan, disagreed with Dr Walker’s opinion, Dr O’Sullivan agreed with Dr Bell that the L4/5 laminectomy and decompression surgery was reasonably necessary to treat the applicant’s left leg sciatica which was predominantly caused by stenosis at the L4/5 level. Dr O’Sullivan expressed the opinion that the stenosis at the L4/5 level was particularly contributed to on the left side by a disc herniation, being an annular tear of the L4/5 disc, which was sustained in the accepted work injury, on a background of underlying degenerative changes.
Medical evidence consistently shows, and it is not in dispute that, on 22 March 2016, the applicant underwent an L4/45 laminectomy and decompression of the left L5 nerve root, performed by Dr Bell.
Medical evidence also consistently shows, and it is not in dispute that, the applicant subsequently developed a significant and severe spinal and brain infection, which included multiple spinal abscesses and brain empyemas.
An MRI Brain and Whole Spine on 6 February 2017 showed, within the surgical bed at the L4 laminectomy site, bilateral L4/5 joint effusions and locules of collection, which was likely right L4/5 septic arthritis. It showed crowding of the cauda equina and no definite cord oedema was demonstrated. It also showed cerebella extra-dural abscesses within the posterior fossa.
In May 2017, Dr Bell reported that the applicant was found to have septic arthritis of the facet joints at L4/5 following the surgery and that recent MRI showed some stenosis at the L4/5 level and evidence of recent facet joint arthritis.
The applicant’s evidence is that, as a result of the accepted injury, and subsequent spinal infection, she suffers from ongoing back and leg pain and various ongoing disabilities. These include: pain and restriction of movement in the back and legs; difficulty sitting or standing for long periods; difficulty lifting and carrying heavy items; difficulty bending or squatting; poor balance; difficulty walking long distances and over rough or uneven ground; difficult running; difficulty performing household chores; and bowel and bladder incontinence. As I noted above, the applicant’s credibility was not challenged and she was not subjected to cross-examination.
The medical evidence in relation to the applicant’s pain and impairments subsequent to the surgery is somewhat limited and there appear to be some chronological gaps in the treating medical evidence.
As noted above, incidents of the applicant experiencing urinary incontinence were reported by treating doctors, Dr Yamen in September 2013, by Dr Pope in December 2013, by Dr Bell in March 2016.

In 2013, Dr Pope reported that the applicant did not have bowel incontinence but she did experience perineal numbness when she had severe back and leg symptoms.
In 2015, Dr Bell reported that the applicant’s bladder and bowel function were currently normal. Dr Bell noted that the applicant walked with an antalgic gait.
As noted above, various treating medical evidence reported the applicant sustaining falls in the period between the accepted work injury in 2010 and the surgery in 2016.
Various Falls Risk Screening Assessments conducted in respect of the applicant in February 2017, when she was receiving inpatient hospital treatment for a lumbar spine problem, recorded faecal incontinence, issues with mobility and a high fall risk. They did not record any history of the applicant having fallen within the previous two months.
There is no treating medical evidence that the applicant experienced urinary incontinence nor bowel incontinence subsequent to the surgery and infection, apart from January 2017, when incidents of the applicant experiencing bowel problems (frequent bowel motions with blood clots) and poor mobility were reported during the applicant’s inpatient hospital treatment for severe back pain.
During 2017 and 2018 Dr Bell and Dr Whitmill reported that the applicant experienced back pain and severe referred leg pain.
In September 2020, Dr Whitmill recorded that since the infection, the applicant’s activities of daily living were reportedly reduced.
Turning to the independent medical evidence, in November 2021, Dr O’Sullivan reported that the applicant reported an increase in the severity of her back pain and referred leg pain over the previous four years, numbness in her feet, frequent falls as a result of the persistent pain in her back and legs, no sensation with bladder and bowel and problems with bladder and bowel control. Dr O’Sullivan also reported that the applicant had an abnormal gait, she walked with a stick and was unable to stand on her heels or toes. Dr O’Sullivan expressed the opinion that the applicant had developed a cauda equina lesion as a result of an abscess and osteomyelitis of the L4/5 facet joint which developed as a consequence of the L4/5 surgery.
In February 2022, Dr Walker reported that the applicant reported constant lower back pain which radiated into both legs and numbness of her legs, including the perineal regions. Dr Walker noted that the applicant reported a degree of urinary incontinence but did not complain of anorectal problems. Dr Walker noted that the applicant used a stick for support, had a wide based gait and could not attempt a tandem gait. Dr Walker stated that the applicant’s current condition related to her lumbar canal stenosis and the catastrophic infection suffered as a result of the surgery. However, because he believed that the effects of the accepted work injury would have resolved had there not been pre-existing and ongoing lumbar canal stenosis, Dr Walker did not accept that the conditions were a result of the applicant’s accepted work injury.
In the context of the evidence as a whole, I find the opinion of Dr O’Sullivan to be particularly compelling as it seems to provide a considered and logical explanation of the applicant’s medical history, symptoms and impairments in the context of the whole of the evidence. For reasons that follow, I do not accept the respondent’s submission that Dr O’Sullivan’s opinion is based on an incorrect history because it was not based on the correct reason for the spinal surgery.
I note that Dr O’Sullivan’s opinion is largely consistent with the evidence of the applicant’s treating surgeon, Dr Bell, and treating general practitioner, Dr Whitmill. It is also consistent, in some material respects, with the opinion of Dr Walker, notwithstanding that Dr Walker denied a causal relationship between the applicant’s ongoing symptoms and impairments and the accepted work injury on the basis of a pre-existing lumbar canal stenosis.
I accept that the respondent’s submissions do have some force and I accept that there are some difficulties with the medical evidence which I have set out above.
Nevertheless, considering the evidence as a whole and notwithstanding the difficulties with the medical evidence, I accept the applicant’s evidence that she suffers impairments to station, gait, bowel and bladder.
I do not accept the respondent’s submission that the medical evidence does not establish that the spine surgery was reasonably necessary as a result of the accepted work injury.
Considering the evidence as a whole, I prefer and accept Dr O’Sullivan’s opinion that the that the stenosis at the L4/5 level was particularly contributed to on the left side by a disc herniation, being an annular tear of the L4/5 disc, which was sustained in the accepted work injury, on a background of underlying degenerative changes. On that basis, I am satisfied and find that the L4/5 laminectomy and decompression of the left L5 nerve root surgery, performed by Dr Bell, on 22 March 2016, was reasonably necessary as a result of the applicant’s accepted lumbar spine injury on 19 May 2010. I accept that various alternative treatments had provided no enduring relief and, in all of the circumstances, the surgery was a reasonably necessary treatment to address the applicant’s ongoing pain and symptoms.
Further, applying the common-sense test to evaluate the causal chain, it seems to me to be a logical and most likely chain of events, and I accept, that the applicant has experienced a consequential condition of infection in her lumbar spine brain which resulted in neurological impairments to station, gait, bowel and bladder as a result of lumbar surgery performed in March 2016.
Having regard to the evidence as a whole, I do not accept that there is any other significant intervening factor, apart from the accepted work injury, which was causative of the applicant’s reported pain, symptoms and impairments. Further, I do not accept the respondent’s submission that one or more of various intervening acts broke any apparent chain of causation between the applicant’s accepted lumbar spine injury, her condition, symptoms and any impairments.
Further, I do not accept the respondent’s submission that the existence of any causal nexus between the alleged impairments and the surgery, as alleged by the applicant, is inconsistent with the existence of certain impairments prior to the surgery. To the contrary, having regard to the evidence as a whole, I consider that the various medical evidence of the applicant’s symptoms and impairments after the accepted injury and prior to the surgery supports the existence of such a causal connection.
On that basis, I find that the applicant sustained a consequential condition of infection in the lumbar spine, which resulted in neurological impairments to station, gait, bowel and bladder, as a result the accepted injury to her lumbar spine sustained on 19 May 2010

Referral to Medical Assessor

Having made these findings, it is appropriate for me to remit the matter to the President to be referred to a Medical Assessor for an assessment of WPI in respect of the relevant injuries and consequential condition, with a date of injury of 19 May 2010.
All of the materials admitted in the proceedings will be included in the referral.

SUMMARY

Accordingly, I make the following declaration:
(a) the lumbar decompression surgery performed by Dr David Bell, orthopaedic surgeon, on or about 22 March 2016, was reasonably necessary as a result of the accepted injury to the applicant’s lumbar spine sustained on 19 May 2010.
Further, I make the following findings:
(a) the applicant sustained a consequential condition of infection in the lumbar spine and brain, which resulted in neurological impairments to station, gait, bowel and bladder, as a result the accepted injury to her lumbar spine sustained on 19 May 2010.
Accordingly, I order as follows:
(a)    the matter is remitted to the President for referral to a Medical Assessor for assessment as follows:
Date of injury:        19 May 2010 (with consequential conditions).
Body parts:            lumbar spine
Nervous system         station and gait
bladder function
anorectal impairment
TEMSKI/scarring
Method:                  whole person impairment.
(b)    The materials to be referred to the Medical Assessor are to include:
(i)ARD and attachments, and
(ii)AALD dated 4 October 2023 lodged by the respondent and attachments.

[2023] NSWPIC 667

12 December 2023