(a) Application to Resolve a Dispute, dated 22 November 2024, and attached documents;

(b) Reply to the Applicaton to Resolve a Dispute, dated 13 December 2024, and attached documents;

(c) Application to Lodge Additional Documents dated 26 February 2024, lodged by the respondent containing an undated report from Dr Zhao;

(d) Application to Lodge Additional Documents dated 27 February 2024, lodged by the respondent containing a series of clinical records;

(e) Dr Zhao's report titled "Medical Certificate" dated 12 November 2024, lodged and served by hand by the respondent during the conciliation conference on 27 February 2025;

(f) report of Dr Haig, dated 24 March 2023 (the "First Report"), lodged and served by the respondent on 6 May 2025, and

(g) a copy of this Certificate of Determination - Consent Orders.

1. This matter concerns a claim for lump sum compensation, pursuant to s 66 of the Workers Compensation Act 1987 (1987 Act), in respect of an accepted left lower extremity injury and disputed lumbar spine condition. The issue requiring resolution is whether the applicant sustained an injury to his lumbar spine under ss 4(a) and 4(b) of the 1987 Act.
2. For the reasons discussed below, the worker's claim for compensation is successful.

1. On 2 March 2019, the applicant, Mu Guang Lin, was working as a labourer for the respondent, Axis Commercial Pty Ltd ATF Axis Commercial Unit Trust, when he fell from a ladder at a building site. The ladder shifted and the applicant's right leg became caught and he fell to the ground. He suffered a severe fracture to his left tibial plateau which required multiple surgical procedures. The applicant also claims that he injured his lumbar spine as a result of this incident.
2. The applicant has been in receipt of weekly benefits and medical expenses for the accepted left leg injury.
3. The respondent's insurer issued a notice and review, on 14 June 2023 and 6 July 2023, pursuant to ss 78 and 287A of the Workplace Injury Management and Workers Compensation Act 1998, denying liability in respect of the lumbar spine.
4. On 22 November 2024, the applicant commenced proceedings in the Personal Injury Commission (Commission) seeking lump sum compensation in respect of injury to the left leg and lumbar spine. This was followed by lodgment of a series of material from the parties, several Commission events and directions for written submissions. This has been further noted below but is not significant other than to explain the long procedural history.

1. The following substantive issues remain in dispute:

(a) whether the applicant sustained a personal injury on 2 March 2019 to the lumbar spine (ss 4(a) and 9A of the 1987 Act), and

(b) whether, in the alternative, the applicant sustained an aggravation, acceleration, exacerbation or deterioration of his lumbar spine condition on 2 March 2019 (s 4(b) of the 1987 Act).

1. The parties agreed that the matter is to be remitted to the President for referral to a Medical Assessor for assessment of whole person impairment to the left lower extremity (including scarring) and the lumbar spine, but the latter only where injury is found.

PROCEDURE BEFORE THE PERSONAL INJURY COMMISSION

1. On 21 January 2025, the parties attended a preliminary conference during which the issues in dispute were confirmed. The applicant also indicated that he had no intention to undergo the recommended left total knee replacement surgery or the lumbar spine surgery.
2. On 27 February 2025, the parties attended a conciliation conference and arbitration hearing. Mr Jon Trainer, of counsel, appeared for the applicant instructed by Walker Law Group. Mr Paul Rickard, of counsel, appeared for the respondent instructed by Lee Legal Group.
3. Due to time constraints an agreed timetable was set for the lodgment of written submissions. The timetable was unusually drawn out for reason of the applicant's counsel taking leave.
4. The parties lodged and served written submissions in respect of the agreed issues in dispute. In the applicant's submissions there was reference to deficiencies in the respondent's independent medico-legal evidence of Dr Haig. This was not addressed in the respondent's submissions in reply but raised again in the submissions (and subsequent amended submissions) in response by the applicant. The applicant in submissions in response invited the respondent's solicitor to confirm whether Dr Haig's reports were complete or whether there was an additional report not in evidence.
5. In view of the applicant's submissions, a series of exchanges took place between the parties and the Commission. On 6 May 2025, the respondent's solicitor lodged and served the further report of Dr Haig dated 24 March 2023 (First Report) which it had not received until that day. This report was in addition to (and preceded in time) the report of Dr Haig also dated 24 March 2023 attached to the Reply.
6. Following receipt of the First Report of Dr Haig, a series of further exchanges took place between the Commission and the parties regarding the admission of that report into the proceedings. The respondent sought the admission of the report and the applicant objected. The parties were unable to reach agreement on the papers and a further conference was held on 27 May 2025. Mr Jon Trainer, of counsel, appeared for the applicant instructed by Walker Law Group. Mr Murray, solicitor of Lee Legal Group, appeared for the respondent.
7. Following a lengthy period of conciliation the matter proceeded to arbitration hearing on the issue of whether the First Report of Dr Haig dated 24 March 2023 ought to be admitted into the proceedings. Part-way through the applicant's submissions he conceded that he was not prejudiced if the report were admitted, noting that the respondent only sought to provide submissions in respect of paragraph 7 and the paragraph under the heading "opinion" of that document. The applicant then withdrew the objection and the report was admitted into the proceedings. The parties provided oral submissions on the content of that report to the substantive issue in dispute. Those submissions were recorded.
8. 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.

1. The following documents were in evidence before the Commission and considered in making this determination:

(a) Application to Resolve a Dispute, dated 22 November 2024, and attached documents;

(b) Reply to the Applicaton to Resolve a Dispute, dated 13 December 2024, and attached documents;

(c) Directions, dated 21 January 2025, 28 February 2025, 10 March 2025 and

14 May 2025;

(d) Application to Lodge Additional Documents (ALAD - 1) dated 26 February 2024, lodged by the respondent containing an undated report from Dr Zhao;

(e) Application to Lodge Additional Documents (ALAD - 2) dated 27 February 2024, lodged by the respondent containing a series of clinical records;

(f) Dr Zhao's report titled "Medical Certificate" dated 12 November 2024, lodged and served by hand by the respondent during the conciliation conference on 27 February 2025;

(g) the parties written submissions in response to the Directions issued, and

(h) report of Dr Haig, dated 24 March 2023 (the First Report), lodged and served by the respondent on 6 May 2025.

1. On 27 February 2025, the respondent sought to press the admission of ALAD-1 over an objection of the applicant, together with ALAD-2 and the further material from Dr Zhao, the "Medical Certificate" dated 12 November 2024, to which the applicant did not raise an objection.
2. On 20 May 2025, the applicant withdrew its objection to the admission of the First Report of Dr Haig dated 24 March 2023, lodged and served on 6 May 2025.
3. For reasons which have been recorded, ALAD-1 and ALAD-2, the "Medical Certificate" of Dr Zhao and the First Report of Dr Haig dated 24 March 2023 were admitted into the proceedings pursuant to r 67C of the Personal Injury Commission Rules 2021. The documents were admitted as I was satisfied the introduction of this material was necessary to facilitate the just, quick and cost-effective resolution of the real issues in these proceedings. The reasons for admission of these additional documents have been recorded. To the extent necessary, I dispense with the requirement to lodge an Application to Lodge Additional Documents attaching the First Report of Dr Haig dated 24 March 2023 and the Medical Certificate of Dr Zhao dated 12 November 2024.

1. In evidence is the applicant's statement dated 21 November 2024. He provides a history of the incident of 2 March 2019 when he fell from a ladder when trying to attach metal pieces to a frame on the exterior of a building. He states:

"I was standing on a ladder and was in the air approximately 2 metres. As I applied force to secure the metal, the ladder began to shift to the left. In a sudden moment, my right leg became caught in the ladder, and I fell, landing flat on my back."

1. The applicant states that he sustained a severe left tibial plateau fracture that required several surgical procedures, on 3 March 2019, 8 March 2019, 15 March 2019 and

30 May 2024. The procedures had limited success and physiotherapy exacerbated his pain. 2. The applicant states that since the work-related injury he has experienced "significant numbness" in his left leg, ongoing pain in his left knee and these symptoms have worsened overtime. He adds that he continues to "experience ongoing and persistent back pain".

1. On 2 March 2019, the applicant was conveyed from the building site (where he fell from the ladder) by ambulance to Wollongong Hospital. The ambulance electronic medical record, dated 2 March 2019, records a description of the incident. It records that the applicant fell from a ladder from around 1.7m. It records that the applicant "reached up to grab a level, fell. Patient said through interpreting, he landed on his feet". It notes swelling and deformity of his left leg. It also notes the applicant was given methoxflurane.
2. The applicant attended Wollongong Hospital for acute care following his injury. The hospital inpatient front sheet records that the presenting problem is a "[f]all from ladder, landed on feet, left proximal tibial pain, knee pain". The Emergency Documentation Triage records note that the applicant "[l]anded directly on bilateral feet" and "No c.o lumber [sic] pain".
3. The hospital progress notes recorded by Dr Sunderland, record a history "obtained with friend at bedside and interpreter". The history is recorded as follows:

• - lost balance, no other symptoms prior to falling
• - fell onto right side, mainly right knee
• - left leg/shin got stuck in ladder on fall

• - has not walked since due to the pain
• - ambulance immobilised and strapped leg
• - pt complaining of some numbness/sensation change to plantar surface left leg

1. The applicant was discharged from Wollongong Hospital for transfer to Liverpool Hospital to be closer to family. The Wollongong Hospital discharge referral records that the applicant "[f]ell off 1.5 step ladder, landed with anterior tibia on metal beam" and notes surgery was undertaken on 3 March 2019. The discharge plan includes a list of medications ordered, including celecoxib, enoxaparin, paracetamol and tapentadol.
2. The Liverpool Hospital discharge records, dated 20 March 2019, notes a history of the incident. It does not refer to the lumbar spine. It notes the applicant underwent an operation in respect of the left tibial plateau fracture on 13 March 2019 under the hand of Dr Laird.

1. On 29 December 2017, the applicant attends on his treating general practitioner at Auburn Healthcare Centre. The entry records "CO back pain" and "[p]revious injury to lower back". The applicant is referred for a CT of the lumbar spine but it is unclear whether this scan was undertaken.
2. On 23 March 2019, the applicant attends on his treating general practitioner at Auburn Healthcare Centre, Dr Lian Zhao. Dr Zhao records a history of the left leg injury/fracture, attendance at hospital, and surgery.
3. The applicant then attends Auburn Healthcare Centre on approximately 12 occasions between late March and 7 April 2019 for his left leg, largely for dressing change.
4. It is not until 7 April 2019, when the applicant attends on Dr Aaron Cheung, treating general practitioner at Auburn Healthcare Centre, that a record of the back appears again. Dr Cheung records the reason for visit is "[c]hronic back pain".
5. The applicant then attends on Auburn Healthcare Centre on multiple occasions for review of his left leg.
6. On 10 October 2019, Dr Zhao records current symptoms to include "1. left leg pain", "2. back pain", "3. limping" and "4. dizziness after insomnia due to pain".
7. There are several further clinical entries, predominantly for ongoing review of the left leg.
8. On 11 September 2020, Dr Zhao records ongoing issues with the left leg and also "back pain for a few years worsening since left leg pain".
9. On 17 September 2020, Ms Joyce Low, from Auburn Healthcare Centre, records the reason for visit being "[l]ow back pain radiating to leg". The entry records a history of bilateral lower back pain more on the right which started three to four years ago and getting worse over one year. It also records the applicant had a "lower back injury 3-4 years ago after carrying heavy items." It was noted that there was a "[s]uspected disc herniation and L4/L5 nerve root mild compression". It further records:

"Chronic lower back pain associated to repetitive strains at work, lack of functional muscles and control, sedentary lifestyle, sitting for long hours, and poor sitting and standing postures for long hours."

1. On 19 September 2020, the applicant attends on Ms Low again for treatment for low back pain radiating to leg. The entry records that the applicant continues to have "lower back pain more on the right". It repeats the history of a lower back injury three to four years ago after carrying heavy items and suspected disc herniation and L4/L5 nerve root mild compression.
2. On 20 September 2020, Dr Zhao records that the applicant was seeing a chiropractor for his back pain which was improving "a bit".
3. The applicant then attends on Ms Low again on 24 September 2020, 19 November 2020 and 26 November 2020 and also Dr Zhao on 28 September 2020, 14 November 2020 and 10 February 2021 for treatment of his low back.
4. On 14 and 24 March 2021 and 14 May 2021, Dr Zhao records the applicant has had "back pain for 6 months" and cannot walk due to pain. By 14 June 2021, Dr Zhao records back pain radiating to left leg.
5. The applicant attends on Auburn Healthcare Centre on several further occasions. On 10 December 2021, Dr Zhao records the applicant's "left leg" was wasting associated with back pain and that he was undertaking exercise physiotherapy.
6. It is not until 10 May 2022 that there is a further attendance in respect of the back, where Ms Low records bilateral low back pain more on the right. The applicant attends on Ms Low again for four further occasions in May and June 2022 for the lower back.
7. There are no further relevant clinical entries, and the clinical records appear to cease around mid-2023. However, Dr Zhao provides an undated report in response to a letter of instruction by the applicant's solicitor dated 29 October 2024. Dr Zhao notes that he last saw the applicant on 16 September 2022. Dr Zhao records that "10/10/2019 back pain started". In response to a question about his "[c]onclusions - your opinion in relation to the worker's injury and diagnosis of current condition and the rationale for your opinion", Dr Zhao records "agree with Dr Hon Haig and Work force Australia."
8. In response to a specific question to provide views on causation, Dr Zhao records:

"His back pain occurred 6 months after leg injury. CT lumbar spine showed no fracture but showed disc disease at L3/4 and L4/5, osteophytes and foraminal stenosis at the level of L3/4 and L4/5, the finding indicates the lumbar pathology is likely from a chronic process, not by trauma or injury.

The work injury is not a substantial contributing factor to his lumbar spine pathology found from CT scan."

1. In response to a further specific question as to whether he agrees with the opinion of Dr Haig expressed in his report of 24 March 2023 that the lumbar spine injury has not resulted from the work-related accident, Dr Zhao records that he "respect Dr Ron Haig's opinion." He latter adds that Dr Haig is "a specialist, and has more expertise than a GP."

1. The clinical notes from Hurlstone Park Specialist Medical Centre record a history of chronic low back pain with left L4 radiculopathy from 2021. In the first clinical entry of Dr Arthur Chesterfield-Evans, dated 17 October 2022, there is a history of the 2019 incident and treatment. It records that the applicant was unhappy with Dr Zhao as he "was not standing up for him when his back was denied because knee took precedence." It records past history of "minor back muscle aches after heavy exercise before the accident but never any real pain".
2. On 17 October 2022, Dr Chesterfield-Evans, refers the applicant to Dr Damodaran for review in respect of his back, noting the history of the fall and that the back pain "seems to have been somewhat overlooked".
3. On 19 November 2024, Dr Chesterfield-Evans provides a report to the applicant's solicitors. Dr Chesterfield-Evans notes he initially examined the applicant on 17 October 2022 and then numerous times thereafter and most recently on 18 November 2024 with a mandarin interpreter. He records a history of the fall as follows:

"He was on an A frame ladder about 1.8m from ground and fell sideways with his Right leg caught in the ladder. The ladder and his heavy tool bag around his waist landed on him. He landed with his Left leg straight (tibial plateau fracture), then landed on his backside and hurt his back.

The pain in his left knee was extreme and excluded all else at the time of his injury. The ambulance came and gave him gas that helped."

1. Dr Chesterfield-Evans explains that the applicant left Dr Zhao and came into the care of his practice because he felt that "the back had been injured at the time of his fall, and Dr Zhao was not willing to stand up for him when the insurer declined to acknowledge this situation".
2. Dr Chesterfield-Evans comments on causation. He says that the applicant had a "bad fall" which was sufficient to cause major and lasting damage to his knee. He adds that as part of the fall the applicant continued to the ground "landing hard on the base of his spine". He further adds that there was a "great likelihood of significant injury", notes there was toe weakness and leg numbness at the time. Dr Chesterfield-Evans says that "[n]aturally the treatment system would have concentrated on his knee and the large amount of analgesia for the knee would have also greatly relieved his back symptoms." He further adds that the applicant has "little English and tends not to initiate conversations in English, compounded by ai cultural reticence."
3. Dr Chesterfield-Evans notes that the applicant was working normally and well pre-injury and his back pain and disc lesion was a large problem after the injury. He adds that it is "difficult to believe that anything other than the fall damaged his back".

1. On 4 May 2021, Dr Martin Laird, treating orthopaedic surgeon, provides a report noting it had been over two years post the left leg surgery. He records complaint of knee pain and he gathers that the applicant is "also getting some back pain". He suggests removal of the metal screws in his knee which was causing irritation.
2. On 27 September 2021, Dr Laird provides a further report. He notes he reviewed Dr Haig's report of 12 July 2021. He states that he "is in agreement with Dr Haig's findings and has no further comment to add".
3. On 19 May 2023, Dr Calvin Chien, treating orthopaedic surgeon, provides a report to Dr Chesterfield-Evans. Dr Chien provides a diagnosis of left knee post-traumatic osteoarthritis and hardware irritation. He notes that the applicant "aggravated his lower lumbar spine" in the incident.
4. On 13 June 2023, Dr Yingda Li, treating neurosurgeon, provides a report. The report notes that the applicant attended with the benefit of a Mandarin interpreter who helped translate. Dr Li records a history of the incident and notes the applicant reports radicular sounding left leg symptoms, radiating to the big toe, separate from the knee problems. He had a left L5 periradicular injection which improved his symptoms.
5. Dr Li diagnoses the applicant with chronic left L5 radiculopathy with weakness, plausibly secondary to left L4/5 disc herniation and spondylotic stenosis.
6. On 26 September 2023, Dr Laird provides a further report. He records ongoing pain in the knee which was "being complicated by back pain in recent times". He notes an in-person interpreter needs to be organised for each appointment with the applicant.

1. On 22 March 2021, the applicant underwent a CT scan of the lumbosacral spine. In the report, the clinical history notes back pain, tender L3-5. Findings of mild central and severe left foraminal stenosis compressing the left L4 nerve root and mild right foraminal stenosis are noted. L3/4 and L4/5 disc disease is also noted as causing mild foraminal stenosis.
2. On 24 October 2022, the applicant underwent an MRI of the lumbar spine. In the report, the clinical history is recorded as a "fracture left tibial plateau, also back pain with radiculopathy L5". Findings of a focal central disc protrusion and left foraminal disc protrusion at L4/5 impinging the traversing left L5 nerve root in the subarticular recess, together with mild-moderate osteoarthritis of the lumbar spine, are recorded.
3. On 15 May 2023, the applicant undergoes a further lumbar spine MRI. In the report, the clinical history records "[h]ad fracture left tibial plateau, also back pain with radiculopathy L5." Findings of focal central disc protrusion and left foraminal disc protrusion at L4/5 impinging the traversing left L5 nerve root and mild-moderate osteoarthritis are noted.

1. In evidence are four reports prepared by Dr Ron Haig, orthopaedic surgeon and independent medical expert qualified by the respondent.
2. On 12 July 2021, Dr Haig provides his initial report. He took a history of the injury, with the assistance of a Mandarin interpreter. He records that the applicant "fell a height of about 1.7 metres from an A frame ladder with the front of his left knee/upper tibia hitting the edge of the stair." He records a history of the surgeries undertaken in respect of the left knee. He also records that the applicant continues physiotherapy though this is now mainly for his low back.
3. Dr Haig records that the applicant complains about his back. He adds that from the documentation "it would appear these are recent, but he states he hurt his back in the accident." He adds that "[a]fter discharge from hospital, he was aware of pain in the back with bending and that is his current complaint." Dr Haig records his findings on examination of the lumbar spine.
4. Dr Haig notes that the applicant states he was aware of pain in his back in the hospital but that he considers it "unlikely he would have sustained any particular injury to his back, the mechanism of the fall being what it was; he falling on the front of the left knee/upper leg". He also refers to the CT scan of the spine and finds that the "radiological changes have likely been present for some time". He finds that the applicant has lumbar spinal canal/exit foraminal stenosis but did not consider this was work-related.
5. In response to a question about incapacity, Dr Haig states "[i]t is likely he had pre-existing spinal canal stenosis, albeit asymptomatic."
6. In response to a further question as to whether the back pain was a symptom of the incident, Dr Haig records:

"I do not consider his complaint of back pain to be a symptom of the incident of 2 March 2019. He has radiologically demonstrated spinal canal/exit foraminal stenosis involving the L4 nerve root on the left side. These changes have no doubt been present for some time though only recently manifesting themselves symptomatically."

1. On 9 September 2022, Dr Haig provides a supplementary report. Dr Haig provides a response to a question regarding the claimed sensation of back pain and whether it is casually related to the applicant's compensable left knee injury. Dr Haig refers to his earlier report of 12 July 2021. He states that the CT scan of the lumbar spine in March 2021 reported various pathologies which would not be inconsistent with a man the applicant's age and he had no reason to attribute them to the injury. He finds that the "more recent complaint of back" was not the result of the compensable left knee injury.
2. On 24 March 2023, Dr Haig provides a further supplementary report. Under the heading "Opinion", Dr Haig records:

"I commented in my original report on his complaint of low back pain suggesting that this came on later. Indeed, there is an imaging request dated 14/3/2021 for a CT scan of the lumbar spine, the clinical details reading 'back pain for six months'. This would suggest that the back pain came on about 18 months after the accident."

1. In response to the following question, Dr Haig records an opinion about the lumbar spine:

"7. Does Doctor maintain the opinion the worker did not sustain an injury to his back in the incident on 2 March 2019? Alternatively, does Doctor consider the worker suffered a secondary or consequential injury to his back as a result of his left leg injury?

I have provided my reason why I do not believe he sustained the injury to his back in the incident on 2 March 2019. I do not believe the later development of low back pain and left sided sciatica was a secondary or consequential injury. From the documentation available to me, complaints started more than a year after the subject injury."

1. Also on 24 March 2023, Dr Haig provides a further supplementary report. He refers to the earlier report where he responds to a question in the respondent's letter of instruction. He provides comment on Dr Gehr's report of 2 February 2023. His report does not address the lumbar spine.

1. On 2 February 2023, Dr Gehr, orthopaedic surgeon and independent medical expert qualified by the applicant provides a report following his examination of the applicant with an interpreter present.
2. Dr Gehr records the applicant's past medical history prior to the incident. He records that there were "no previous problems with cervical spine, thoracic spine, lumbar spine, upper extremities or lower extremities".
3. Dr Gehr records a history of the incident. He notes that "[a]s he fell to the ground, his right leg was stuck in the ladder, but the left leg hit the ground". The applicant had a lot of pain and swelling over his left knee and later underwent surgeries and physiotherapy. He further records that the applicant reports he is having physiotherapy for his back and that he "developed back pain almost from the same time".
4. Dr Gehr provides a diagnosis of left knee plateau, shaft fracture requiring ORIF, lumbar spine discogenic injury with guarding and dysmetria, and secondary osteoarthritis in left knee. He refers to the incident resulting in the fracture of the left knee and states "[a]lso at the same time, he developed lumbar spine pain with pain radiating down his left leg" and that on examination he found guarding and dysmetria related to the lumbar spine.
5. Dr Gehr provides an assessment of whole person impairment of 38%, comprising of 16% in respect of range of motion of the left knee, 18% for malrotation of the left knee, 2% for scarring, and 8% for the lumbar spine.

1. The applicant and respondent provided oral submissions during the hearing which were recorded. Those submissions will not be repeated in full but have been considered and will be referred to where relevant.

1. The applicant submits that there is no dispute that the applicant suffered an injurious event on 2 March 2019 and liability for the left lower extremity has been accepted.
2. The applicant submits the pathological and diagnostic basis of the lumbar spine condition is described as both a traumatic disc lesion of the L4/5 intervertebral disc and also as underlying degenerative changes.
3. The applicant refers to the medical evidence in support of a lumbar spine disc injury. Dr Chesterfield-Evans' report dated 19 November 2024, which records that he saw the applicant on 17 October 2022 and arranged an MRI of his lumbar spine which showed a "focal central disc protrusion at L4-5". Dr Li's report, dated 13 June 2023, records "left L4/5 herniation". Dr Gehr's report, dated 2 February 2023, provides a diagnosis of lumbar spine "discogenic injury". These clinical opinions are consistent with the MRI of October 2022 which describes a "focal central disc protrusion and left foraminal disc protrusion at L4/5".
4. The applicant contends that the L4/5 disc lesion has occurred on the background of underlying degenerative changes in the applicant's lumbar spine. The applicant refers to the respondent's evidence of Dr Haig, who was of the view that the applicant's low back complaints resulted from the pre-existing degenerative changes with the doctor describing "lumbar spinal canal/exit foraminal stenosis". The applicant submits that it is likely that Dr Haig's opinion is based on the CT scan dated 22 March 2021 which identifies this pathology. However, Dr Haig was at pains to exclude the lumbar spine pathology, or its aggravation, as being causally related to the injurious event of 2 March 2019.
5. The applicant submits that that the opinions of Dr Chesterfield-Evans, Dr Yi and Dr Gehr should be preferred. Firstly, the Commission is a specialised tribunal and can rely on its specialised knowledge that an MRI scan is more discriminating study than a CT scan, and should be preferred over a CT scan.[1] Secondly, Dr Haig's diagnosis, which appears in his original report and second report, predates the MRI scan.
6. Dr Haig's opinion is based on degenerative changes that were seen in the CT scan. He excludes these changes as causally relevant based on a finding that it had "no doubt been present for some time though only recently manifesting themselves symptomatically". It is unclear what history Dr Haig was given regarding the onset of back complaints. Further, his back complaints, as of July 2021, were not a recent symptomatic manifestation. Dr Zhao recorded a complaint of "chronic back pain" on 7 April 2019 and "worsening back pain since left leg pain" on 11 September 2019. There were back complaints made by the applicant a little over a month after the injurious event.
7. The applicant asserts that the following diagnoses are available:

(a) injury involving both L4/5 disc lesion and an aggravation of underlying degenerative changes in the lumbar spine (most consistent with the CT and MRI scan), or

(b) injury in the form of an L4/5 disc lesion, or

(c) injury by way of aggravation of underlying degenerative changes in the lumbar spine.

1. The applicant submits that he sustained an injury under s 4(a) of the 1987 Act to his lumbar spine on the basis of the following:

(a) the applicant describes in his statement evidence the injurious event in terms consistent with a low back injury, describing "landing flat on his back";

(b) the applicant describes in his statement evidence persistent numbness in his left leg since the injurious event, consistent with a discal injury at L4/5 causing radicular pain. The applicant refers to Dr Li's evidence which describes left L5 radiculopathy as plausibly secondary to the disc lesion;

(c) the injurious event was a significant injury, resulting in a fracture of the left tibial plateau. The mechanical forces capable of causing such a traumatic fracture would be capable of causing injury to the low back;

(d) Dr Zhao records chronic back pain on 7 April 2019. While the records refer to "chronic" the previous entry of back complaint was on 29 December 2017, and

(e) Dr Zhao records, on 11 September 2020, a history of back pain "for a few years ... worsening since left leg pain" which the applicant submits is indicative of a back injury on 2 March 2019.

1. The applicant submits that a finding of injury involving an L4/5 disc lesion and an aggravation of underlying degenerative changes in the lumbar spine is available under s 4(a) of the 1987 Act.[2]
2. The applicant submits that a finding that the applicant sustained an aggravation of underlying degenerative changes in the lumbar spine under s 4(b) of the 1987 Act would be dependent on a finding that the applicant suffered an injury to his lumbar spine on 2 March 2019. The applicant then repeats his earlier submissions.

1. The respondent refers to the injurious event and the complaint of lumbar spine injury.
2. The respondent refers to the evidence of Dr Haig, who was of the view that the applicant's back complaints were of a recent origin and the mechanism of the fall was such that it was unlikely that he would have sustained any injury to the back.
3. The respondent submits that this is supported by the Discharge Referral of Wollongong Hospital which records "[f]ell off 1.5m step ladder, landed with anterior tibia on metal beam". The triage notes also record that the applicant "[l]anded directly on bilateral feet." The respondent submits that the NSW Ambulance records contain a similar history.
4. The respondent refers to the recency of the onset of lumbar pain confirmed by the evidence of Dr Laird, dated 4 May 2021, which he records the applicant was complaining of back pain.
5. The respondent submits that Dr Haig did not consider the complaints of back pain were a symptom of the injurious event. He noted the CT scan of 22 March 2021 which demonstrated degenerative changes which were likely to have been present "for some time".
6. The respondent then refers to the clinical notes, regarding back complaint. On 29 December 2017 there is a record of "Chronic back pain", "Previous injury to lower back" and a CT scan of the lumbar spine. The history recorded on the CT report is "Chronic lower back pain, working as a physical worker". The respondent submits that this history is at odds with Dr Gehr's, who records there are no previous problems of the lumbar spine. The respondent notes that Dr Haig records a similar history.
7. The respondent submits that the contemporaneous records of the mechanism of the fall in the hospital triage notes and NSW Ambulance records contradict the applicant's statement that he fell landing flat on his back. In addition, the respondent notes that the Wollongong Hospital triage notes record "No c.o lumber [sic] pain". There is also no reference to the back injury or pain in the Liverpool Hospital records, where the applicant was admitted from 8 March 2019 to 20 March 2019, or the ambulance records.
8. The respondent contends that:

(a) the applicant had a pre-existing chronic back condition, which resulted in a CT scan being carried out in 2017;

(b) there were no contemporaneous complaints of back pain or back injury, and

(c) the mechanism of injury was on the basis of the Wollongong Hospital records not as alleged by the applicant.

1. The respondent submits that the reference to back complaint by Dr Zhao in April and September 2019 is a reference to chronic back pain and cannot be read as referring to an injury occurring only a month before. It is intended to refer to the chronicity of the applicant's back pain since 2017. Further the reference to the history to Dr Zhao on 11 September 2019 relates to a consultation on 11 September 2020, some 18 months after the injurious event.
2. Following the 11 September 2020 consultation with Dr Zhao, the respondent submits that the applicant then consulted with Ms Low for chiropractic treatment on 17 September 2020. In Ms Low's notes she records bilateral lower back pain "getting worse over 1 year", which the respondent submits takes the timeframe back to September 2019. This timeframe is consistent with Dr Zhao's description "10/10/2019 back pain started" in his undated letter to the applicant's solicitor which is in evidence. The respondent submits that Dr Zhao expressed his agreement with Dr Haig and Dr Laird.
3. The respondent submits that in the absence of any contemporaneous medical records of a back injury, reliable account from the applicant as to his prior history of back complaint and in relation to the mechanism of the fall, the Commission could not be satisfied that the applicant sustained an injury to his back as alleged. The only matter to be referred to the Medical Assessor is the left lower extremity flowing from the injurious event.

1. The applicant provides two sets of submissions in reply, however, only relies on the amended submissions in reply.
2. A significant focus of the amended submissions in reply address the completeness of Dr Haig's First Report dated 24 May 2023. The applicant withdrew a significant proportion of those submissions during a subsequent conference noting the admission of the report of the First Report of Dr Haig dated 24 May 2023.
3. The applicant submits that Dr Haig's second report dated 24 May 2023 should not be accepted due to its deficiencies. The applicant also submits that Dr Haig's first two reports did not consider the MRI scan and the third report (namely, the First Report dated 24 May 2023) failed to consider it.
4. The applicant contends that if the foundational opinion of Dr Haig is rejected the consequential opinions of Dr Zhao and Dr Laird, which the respondent relies, should also be rejected.
5. The applicant submits that the presence of a single complaint of low back pain on

29 December 2017 contained in the clinical notes does not logically exclude the applicant suffering a low back injury on 2 March 2019. 6. The complaint of low back pain on 29 December 2017 must be considered in context. While the notes describe "chronic" low back pain that chronic pain was not of sufficient severity to warrant any complaint of low back pain in any of the 15 consultations between 15 November 2013 and 28 December 2017 or the 10 consultations between 30 December 2017 and 9 February 2019. Further, the applicant did not have any ongoing treatment for the low back pain (other than a CT scan) after 29 December 2017 and did not take time off work. This suggests that the chronic low back complaint, prior to 2 March 2019, was of little, if any, consequence for the applicant. In this context, the applicant submits the blemishes the respondent describes in the histories provided to Dr Gehr and Dr Haig are inconsequential. 7. The applicant submits that the absence of contemporaneous record of complaint to ambulance officers and at the hospitals must be considered in context:

(a) the applicant was given methoxyflurane by ambulance officers, which is used to treat severe pain caused by trauma and likely to have masked the effects of any back injury;

(b) between 2 March 2019 and 7 March 2019, while an inpatient at Wollongong Hospital, the applicant was given ongoing pain killing medication, including anti-inflammatories and opioids. The nature of those medications is such as to have masked the effects of any back injury sustained in the injury;

(c) given the nature and extent of the left leg injury, the fact he underwent surgery on 3 March 2019, the applicant was bed-ridden while at Wollongong Hospital, further masking the effects of the back injury;

(d) while admitted to Liverpool Hospital between 8 and 20 March 2019, the applicant underwent two further surgical procedures on this left knee on 13 and

15 March 2019. The applicant submits that it is to be presumed that for the majority of that admission he was confined to bed such as to mask any back injury, and

(e) the medications on admission to Liverpool Hospital included opioid pain killers and anti-inflammatory medication and opioids on discharge, which would have masked the effects of any back injury.

1. The applicant submits he sustained a severe injury to his left knee, requiring three surgical procedures in the weeks after its occurrence. As a result of that injury and surgical procedures the applicant was required to take extremely powerful pain medications. The absence of back complaints is explicable on the basis of those medications masking back symptoms and the fact that the back symptoms were initially overshadowed by the left knee symptoms.
2. The applicant submits that caution should be given to the use of clinical material as a means of impugning evidence.[3] This caution is relevant to the ambulance notes and clinical notes from the hospital.
3. In respect of the ambulance notes, the applicant notes that it records that he communicated with the ambulance officers "through interpreting". These notes should not be used as a basis for rejecting the applicant's evidence as to the mechanism of injury, as neither the identity of the interpreter, their skill or the accuracy of the actual interpreting is known. In addition, the applicant was suffering the effects of a severe left knee fracture.
4. In respect of the triage notes from Wollongong Hospital, it is not known and unlikely that an interpreter was present at that time. These notes should be contrasted with the clinical notes when the applicant was interviewed by Dr Sunderland, with an interpreter present, that he did in fact fall on his right side. Dr Sunderland's notes are more likely to be accurate; these notes exclude a mechanism of injury of simply landing on his feet as suggested by the respondent. While it is not consistent with the applicant's statement of falling and landing flat on his back, falling 1.7m from the ladder and landing on the right side would be capable of causing the back injury.
5. The applicant refers to the clinical note of 7 April 2019 and urges caution to be had to the term "chronic" in the context of back complaint. The applicant submits that caution should be given to the use of clinical material being treated as definitive and words need to be weighed against the actual mechanism of injury and the complaints recorded in September 2020 of worsening since the injurious event in March 2019.
6. The applicant submits that there may have been a worsening of back symptoms in late 2019 but this does not exclude that there was a back injury on 2 March 2019.
7. The applicant concedes that Dr Zhao and Dr Laird embraced Dr Haig's views, but submits Dr Haig's evidence should be rejected. Dr Zhao and Dr Laird's evidence would likewise need to be rejected as they simply repeat Dr Haig's views. Dr Zhao and Dr Laird do not provide any reasoning process by which Dr Haig's opinion is correct, but simply state in the case of Dr Laird that he is in agreement with Dr Haig and in the case of Dr Zhao that he respects

Dr Haig as he is the specialist with more expertise. These opinions are no more than a bare ipse dixit and cannot be accepted. 8. The applicant also submits that Dr Zhao's reference to worsening left leg pain, recorded in his report of 11 September 2020, is entirely consistent with pre-existing chronic low back pain having worsened following the injury on 2 March 2019. 9. On balance, the Commission should be satisfied that he sustained an injury to his low back on 2 March 2019.

Applicant's submissions in respect of Dr Haig's First Report of 24 March 2023

1. The applicant submits that Dr Haig does not take the matter any further because the applicant is not dealing with a consequential injury. Later onset of back complaints is not relevant to the issue for determination.
2. The applicant submits that to the extent that the doctor adhered to his previous opinion that there was not a back injury in the incident in 2019, this report takes it no further. To the extent of an allegation of a secondary or consequential injury this is not alleged by the applicant and the comment is of no relevance. He has negatived an allegation which has never been made.

Respondent's submissions in respect of Dr Haig's First Report of 24 March 2023

1. The respondent submits that Dr Haig's report is consistent with the balance of his other reports. It confirms his view that the applicant made no complaint of injury or pain at the time of the indexed injury. It is entirely consistent with the clinical material from Auburn Healthcare and Wollongong Hospital, neither of which substantiate the applicant making a complaint of back pain at the time of the 2019 injury.

Applicant's submissions in response in respect of Dr Haig's First Report of 24 March 2023

1. The applicant declined to provide any submissions in response.

1. The applicant bears the onus of proof, to establish his case under s 4 of the 1987 Act, on the balance of probabilities.[4] In order to determine whether the applicant suffered an injury to his lumbar spine I am required to conduct a commonsense evaluation of the casual chain of events and this requires careful consideration of the evidence.[5]
2. Section 4(a) of the 1987 Act defines "injury" as a personal injury arising out of or in the course of employment. There is no compensation payable under s 4(a) of the 1987 Act unless employment is a "substantial contributing factor" to the injury, within the meaning of that phrase under s 9A of the 1987 Act. It is well established that the phrase "substantial contributing factor" involves a causal connection between the employment concerned and the injury.[6] The causal connection must be "real and of substance".[7]
3. In Rail Services Australia v Dimovski,[8] Handley JA stated that where a frank incident aggravated an underlying degenerative condition, it could properly be regarded as injury simpliciter within s 4(a) of the 1987 Act. To establish a personal injury (or "injury simpliciter") there must be evidence of an identifiable pathological change.[9] That the change is connected to an underlying disease process does not prevent the event from being a personal injury.[10]
4. As Deputy President Snell said, in General Education Castle Hill Pty Ltd v Workers Compensation Nominal Insurer (icare),[11]Dimovski provides that it is not an error to find injury under s 4(a) when the elements pursuant to the 'disease' provisions are present. In Dimovski, Hodgson JA stated:

"In my opinion, the decision in Mecha is to be preferred. Section 16 applies only if the injury 'consists in' the aggravation etc of a disease. If there is an event that satisfies paragraph (a) of the definition of injury, and if that is the injury relied on and proved, the circumstance that it aggravated the disease and thus could have supported a case under paragraph (b)(ii) does not mean that this injury 'consists in' the aggravation of a disease. One strange result of the contrary view would be that a frank injury relied on and proved would, if it happened to aggravate a disease, and if incapacity did not commence immediately, be deemed under s 16(1)(a) to have happened at some time other than when it in fact happened."[12]

1. Section 4(b) of the 1987 Act provides that "injury" includes a "disease injury". Section 4(b)(ii) of the 1987 Act provides that a "disease injury" means the aggravation, acceleration, exacerbation or deterioration in the course of employment of any disease. Section 4(b) of the 1987 Act requires that employment be the "main contributing factor" to the aggravation of a disease. It is well accepted that the test of "main contributing factor" is one of causation which involves consideration of the evidence overall.[13] In Av v Aw,[14] Deputy President Snell said "in a matter involving s 4(b)(ii) it is necessary that the employment be the main contributing factor to the aggravation, not to the underlying disease process as a whole."[15]
2. It is well accepted that an aggravation of a disease under s 4(b)(ii) of the 1987 Act "occurs where the experience of the disease by the patient is increased or intensified by an increase or intensifying of symptoms".[16] As Justice Windeyer said in Semlitch:

"[t]he question that each [aggravation; acceleration; exacerbation; deterioration] poses is, it seems to me, whether the disease has been made worse in the sense of more grave, more grievous or more serious in its effects upon the patient."[17]

1. It is accepted that the applicant suffered an injurious event on 2 March 2019, but the mechanism of injury is disputed. The respondent sought to criticise the applicant's history of the mechanism of injury reported and recorded in the evidence in respect of the manner in which he landed after the fall.
2. The evidence on the mechanism of injury is not entirely clear. It is accepted that the applicant fell from a ladder from a considerable height of around 1.7m in the course of his employment. The evidence is also fairly consistent that the applicant's right leg got caught in the ladder as he fell to the ground sustaining a serious injury to his left leg which required multiple surgical procedures.
3. In terms of the manner in which the applicant fell, the evidence provides, in chronological order, that:

(a) the ambulance records note the applicant "said through interpreting, he landed on his feet";

(b) the Wollongong Hospital inpatient sheet records the fall and that the applicant "landed on feet";

(c) the Wollongong Hospital progress notes, recorded by Dr Sunderland, records a history of the event having been obtained with the benefit of a "friend at bedside and interpreter". Those notes record the applicant "fell onto right side, mainly right knee" and that the left leg got stuck in the ladder;

(d) Dr Haig, in a report of 12 July 2021, records the fall and that the left knee/upper tibia hit the edge of the stair;

(e) Dr Gehr, in a report of 2 February 2023, records that the applicant's right leg was stuck in the ladder as he fell to the ground "but the left leg hit the ground";

(f) Dr Chesterfield-Evans, in a report dated 19 November 2024, records that the applicant's right leg got caught when he fell from the ladder and that he "landed with his left leg straight" and "landed on his backside". He also states that as part of the fall the applicant continued to the ground "landing hard on the base of his spine", and

(g) the applicant in his statement evidence, dated 21 November 2024, states his right leg got caught in the ladder and he fell "landing flat on [his] back".

1. There are inconsistences on the evidence as to the actual mechanism of the fall. However, care should be taken when considering the applicant's medical records, and particularly the contemporaneous records. It is well accepted in law that busy doctors sometimes misunderstand or mis-record histories of accidents, particularly when their concern is with treatment of an indisputable injury.[18] Indeed, the hospital records at time appear to confuse the left with the right in circumstances where the undisputed evidence is that the applicant's right leg got caught and he fell sustaining a severe injury to his left leg. There are other factors that give rise to the need to exercise caution regarding the inconsistency in the recorded history of the mechanism of injury. In this regard, I have taken into consideration the following factors:

(a) that English is not the applicant's first language. It is not known what type of "interpreting" the applicant had when conveying the circumstances of the fall to the ambulance officers or the details of the "interpreter" at the bedside when Dr Sunderland took a history of the fall. Indeed, this would have occurred at a time when the applicant was in acute pain and being treated with methoxflurane;

(b) that the applicant was in significant pain, under medication to treat that pain and immobilised for reason of his left leg injury, which would have likely masked symptoms to other body parts such as the lumbar spine, and

(c) that the applicant has focused primarily on his left leg, which is understandable given it required urgent treatment, including surgery.

1. In circumstances where the applicant requires an interpreter as English is not his first language, he was given medication to alleviate his severe left leg pain and the first responders and hospital staff were focused on the applicant's acute injury to his left leg, the inconsistencies in the recorded history of the mechanism of the fall are not determinative.
2. To the extent necessary, I am satisfied on the evidence that the applicant's right leg got caught in a ladder and he fell from a height of at least 1.7m landing on his left side with sufficient force to cause a traumatic injury in the nature of a severe fracture to his left tibial plateau requiring multiple surgical procedures. I do not accept the applicant merely fell landing on his bilateral feet.

1. The respondent sought to argue that there was no work related back injury because of the lack of contemporaneous evidence to the 2019 incident and any complaint of back pain related to the chronicity of the applicant's back pain since 2017.
2. I accept that there is evidence of lumbar spine issues in 2017 which resulted in the applicant being referred for a CT scan. Although it is unclear whether that CT scan took place, and, if it did, the results are not in evidence. Notwithstanding this, the evidence suggests that the back symptoms were either not significant or did not persist to warrant further complaint to a medical practitioner or treatment following the December 2017 consultation (or in the years earlier according to the evidence lodged). It was not until April 2019, a month after the March 2019 incident, that there is a subsequent reference in the medical evidence to back complaint.
3. It is true that in April 2019 and September 2020 the applicant's then treating general practitioner records a reference to chronic back pain. I do not accept that I am able to find that these entries refer to the chronicity of the applicant's back pain since 2017, as the respondent submits. While the April 2019 entry does not refer to the injury in March 2019 there is a clinical entry on 10 October 2019 by Dr Zhao that records a complaint of various symptoms including the back. In that subsequent entry there is no reference to the chronicity of his back symptoms, but there is a reference to symptoms relating to the left leg and pain. By September 2020 the evidence indicates a worsening of back pain "since left leg pain" (which I infer relates to the injury in March 2019) on the background of back pain for some time. While these entries are not significantly detailed, having regard to the totality of the evidence, I am satisfied at least that the entries of October 2019 and from September 2020 are connected to the 2019 incident.
4. I do not consider the reference to chronic back pain in the April 2019 clinical entry, the absence of immediate complaint of lumbar spine pain or the hospital triage notes recording no lumbar pain are determinative of there being no work related back injury. For the reasons set out above, I accept the applicant's sound submissions that the contemporaneous medical evidence in relation to the 2019 incident must be treated with caution (see [128]-[129]).
5. Dr Zhao is of the opinion that the symptoms in the back first arose in October 2019, and presumably this is a reference back to his clinical entry of 10 October 2019 where he records complaint of symptoms in the back. However, as the applicant submits, this does not indicate that the applicant did not sustain an injury to his lumbar spine in March 2019. The evidence indicates that the first record of back complaint is about six months post the March 2019 incident. It also indicates that, at least from September 2020, a worsening of symptoms in the applicant's back since the incident in 2019. This includes nine attendances on his treating general practitioner and five attendances on his chiropractor between September 2020 and Mid-2021 for treatment of his back. This treatment continues into mid-2022, after which the applicant begins to see Dr Chesterfield-Evans from another medical centre where he continues to receive ongoing treatment for his lumbar spine.
6. Consistent with the evidence suggestive of a worsening of symptoms, the applicant attended on Ms Low for chiropractic treatment on several occasions from mid-September 2020. Ms Low records a history of back pain three to four years ago "after carrying heavy items" which was getting "worse over 1 year" (which takes the chronology of complaint back to September 2019 which is consistent with the clinical records of Dr Zhao of complaint from on or about 10 October 2019, being just over six months post the 2019 incident). She also notes that there was a suspected disc herniation and L4/5 nerve root mild compression, but there is no evidence to corroborate or confirm such a diagnosis prior to the 2019 incident. Indeed, the only reference to back complaint prior to the 2019 incident is in December 2017 and there are no earlier references.
7. I make no adverse inference from the fact that there is a gap in the medical evidence from the 2019 incident to onset of complaint in the back post the 2019 incident. Firstly, the initial reference to back symptoms following the 2019 incident was fairly contemporaneous having regard to the October 2019 clinical entry which is just over six months post the 2019 incident. Secondly, the applicant underwent three medical procedures in respect of the left leg in March 2019 and sought extensive follow-up treatment post those procedures which was clearly his medical focus noting the clinical entries. Thirdly, caution is required when dealing with medical records or the absence of records as a means to discount the applicant's reported history in contemporaneous records.[19] Lastly, the evidence supports a workplace injury to the lumbar spine. For the reasons set in this decision, I accept the circumstances of injury described by the applicant and that the 2019 incident caused the applicant's lumbar spine injury.

1. The applicant must establish, on the balance of probabilities, that there has been a definite or distinct "physiological" change or disturbance in his lumbar spine to prove a "personal injury" under s 4(a) of the 1987 Act.[20] The injury must be "sudden" or at least "identifiable".[21]
2. The terms "personal injury" and "disease" are not mutually exclusive categories. An identifiable physiological (pathological) change to the body brought about by an internal or an external event can be a personal injury and the fact that the change is connected to an underlying disease process does not prevent the injury being a personal injury.[22] In other words, a frank incident that acts as an aggravation of a disease process can properly be regarded as an injury simpliciter, under s 4(a) of the 1987 Act.
3. While injury was disputed, much of the submissions were directed to the mechanism of the fall and absence of contemporaneous complaint of lumbar spine symptoms. I have dealt with the mechanism of the fall and the contemporaneity of the evidence above. I will now address the issue of causation.
4. It is not disputed that the applicant has degenerative spondylotic changes in his lumbar spine. This was confirmed in the March 2021 CT scan and subsequent MRI scans. It is also not disputed that the applicant suffers from a L4/5 disc protrusion. The main issue is whether the disc protrusion and an aggravation of the underlying degenerative changes in the lumbar spine were caused by the 2019 incident.
5. I accept that the histories recorded by Dr Gehr and Dr Haig do not note any specific details of past back complaint. However, this does not mean it was not reported. To the extent that the histories recorded are incomplete, for the reasons discussed above, I do not consider it significant because the 2017 back issue did not require ongoing treatment nor was it subject to ongoing complaint until after the incident in 2019. I accept that there must be a "fair climate" on which an expert bases an opinion and exact correspondence between the history recorded and what is established on the evidence is not necessary for the validity of the medical opinion.[23] Having regard to these matters, I do not consider the imperfections in the history of lumbar spine complaint gives me cause to consider that the opinions of Dr Gher or Dr Haig were not prepared in a fair climate.
6. Dr Gehr provides one report, which he records a history of the 2019 incident. He records that the applicant underwent surgeries and physiotherapy for his left leg and that he developed pain in his back "almost from the same time" (presumably a reference to the 2019 incident). He notes the L4/5 disc protrusion found in the MRI scans but does not relate this to the 2019 incident. He diagnoses, having regard to the radiological evidence including the MRI scans, the applicant with a lumbar spine discogenic injury with guarding and dysmetria. He does not provide a comprehensive opinion on causation but his opinion is based on the history recorded and must be considered against the totality of the evidence.
7. Dr Haig provides several reports, most of which focus on the left leg. In his July 2021 report, which is confirmed in his September 2022 report, Dr Haig provides an opinion that the lumbar spine injury was not work-related. Dr Haig's opinion is prefaced on a view of the mechanism of the fall on the front of the left leg and the findings in the CT scan of the spine of 2021 which demonstrates degenerative changes. He finds that the applicant's symptoms in his lumbar spine, while present for some time, only recently manifested symptomatically. However, he fails to have regard to the clinical records of increase in symptoms or how the 2019 incident may have caused an aggravation of an underlying disease condition. He also fails to have regard to the MRI scan which confirms a L4/5 disc protrusion.
8. I agree with the applicant, that Dr Haig's First Report of March 2023, adds nothing further in respect of the injury in dispute for determination. It merely confirms his earlier opinion on causation.
9. I do not accept I can place any weight on the evidence of Dr Zhao or Dr Laird with respect to their opinions on causation of the lumbar spine.
10. Dr Zhao in an undated report provides an opinion, having regard to the CT scan findings, that the lumbar spine pathology is likely from a chronic process not by trauma or the work injury. However, his opinion fails to have regard to the increase of symptoms reported following the 2019 incident and the lack of ongoing complaint and treatment of the lumbar spine prior to that event.
11. Dr Laird does not provide an opinion on causation of the lumbar spine injury other than to state he is in "agreement with Dr Haig's findings". He does not provide an explanation for his agreement or refer to any of the radiological or clinical findings or history.
12. To the extent that Dr Zhao and Dr Laird accept or support the view of Dr Haig, I accept the applicant's submission that these opinions are no more than a bare assertion and fail to provide any evaluation or expose their reasoning process by which they consider Dr Haig as correct. Dr Laird merely states that he is in "agreement" with Dr Haig. Dr Zhao states he "respects" Dr Haig's opinion and defers to his opinion as he is the specialist with more expertise or in his words "has more expertise than a GP". On this basis, the opinions of Dr Zhao and Dr Laid provide no further assistance to the issue of causation.
13. Dr Gehr's opinion is supported by Dr Chesterfield-Evans, who examined the applicant with the benefit of a mandarin interpreter. Dr Chesterfield-Evans records a history that is largely consistent with the applicant's statement evidence regarding the fall, that the initial treatment naturally focused on the issues in the left knee and that the analgesia the applicant took for those symptoms would have "greatly relieved his back symptoms". He adds that the applicant was working normally and well prior to the 2019 incident and found it difficult to believe anything other than the fall damaged his back. His opinion provides a comprehensive explanation that the lumbar spine symptoms were caused by the 2019 incident, and that complaint of lumbar spine pain was masked by symptoms in the left knee and medication undertaken.
14. Dr Gehr's opinion is also supported by Dr Li and Dr Chien.
15. Dr Li diagnoses the applicant with chronic left L5 radiculopathy, which he states is plausibly secondary to left L4/5 disc herniation and spondylotic stenosis. He does not provide a clear opinion on causation to the 2019 incident. However, his opinion must be read against the preponderance of evidence that provides increase in symptoms in the applicant's lumbar spine and confirmation of a L4/5 disc protrusion in 2022.
16. Dr Chien finds that the applicant aggravated his lumbar spine in the 2019 incident. Although, his opinion on causation suffers from the same lack of evaluation as Dr Laird and Dr Zhao and cannot be given significant weight.
17. I prefer the opinions of Dr Gehr, which is supported by Dr Chesterfield-Evans, Dr Li and

Dr Chien. I prefer Dr Gehr's opinion, over Dr Haig. I do not consider I can attach any significant weight to the opinions of Dr Zhao and Dr Laird for the reasons discussed above. 18. The Commission is a specialist tribunal and it can rely on its expertise in understanding the evidence before it and in drawing appropriate inferences.[24] Although I accept that this does not extend to applying a Member's own views of the "aetiology of a disease which is not supported by the evidence".[25] 19. The absence of contemporaneous evidence of lumbar spine complaint is not determinative on the issue of causation, in circumstances where there is other evidence to support the existence of the injury.[26] Indeed the absence of symptoms on or about the 2019 incident and then not until October 2019 and then from September 2020 does not necessarily equate to an absence of relevant pathology. I also accept that care should be taken when considering the applicant's clinical records. That is because it was clear that the focus and primary concern was with the applicant's left leg, which required multiple surgical procedures. Further, clinical notes are rarely a complete record of exchange between the practitioner and patient. To the extent that there is a gap between the 2019 incident and complaint of lumbar spine pain and consistent complaint of pain, on the background of the applicant's primary concern in the left leg, I do not consider this is materially significant.[27] 20. It is not known when the applicant sustained the L4/5 disc protrusion. The L4/5 disc protrusion was not identified in the March 2021 CT scan but confirmed in the MRI reports from October 2022. There is reference to a "suspected" disc herniation and L4/5 nerve root mild compression that occurred prior to the 2019 incident, as noted by Ms Low in 2020, but the evidence does not indicate this was confirmed or diagnosed prior to that incident. Indeed, the evidence suggests that the applicant had no ongoing complaint or treatment in respect of the back following the December 2017 clinical entry until after the 2019 incident. 21. While the L4/5 disc protrusion may have occurred on the background of underlying degenerative changes in the lumbar spine, there is no medical evidence that explains the actual cause or timing. Dr Gehr notes the disc protrusion but does not provide an opinion on causation. Dr Haig does not have regard to the disc protrusion. The other treating practitioners either do not comment on its cause or merely just refer to its existence. Dr Li is the only practitioner which comments that the applicant's condition is secondary to the disc protrusion and degenerative condition. I do not feel actual persuasion that the applicant sustained a traumatic L4/5 disc protrusion as a result of the 2019 incident. However, I accept that the applicant's impairment arising from the disc protrusion coincided with the onset of back complaint following the 2019 incident. I also accept the evidence supports an aggravation of a disease process for the reasons that follow. 22. The totality of evidence provides that on examination there were clinical signs, supported by radiological investigations, which revealed a pathological explanation for the symptoms in the lumbar spine. The evidence demonstrates that the 2019 incident aggravated the pathology that was already in existence. The applicant suffered an increase in lumbar spine symptoms from at least September 2019, on a background of a gap of complaint from December 2017 and L4/5 disc protrusion confirmed in 2022, having regard to the preferred medical opinions this is sufficient to establish an injury that consists in the aggravation of a pre-existing degenerative condition in the lumbar spine. 23. I am satisfied on the balance of probabilities, to a degree of actual persuasion, that the applicant has established that there was an identifiable and distinct pathological change in his lumbar spine in the form of an aggravation of his underlying degenerative lumbar spine condition arising out of or in the course of his employment with the respondent on 2 March 2019. I am also satisfied that this injury should be properly regarded as an injury simplicter, namely, a personal injury pursuant to s 4(a) of the 1987 Act. 24. The parties did not make any specific submissions on the application of s 9A of the 1987 Act. Having considered the factors under s 9A(2) of the 1987 Act, I am satisfied that the applicant's employment with the respondent was a substantial contributing factor to the injury. 25. It follows that the factual and medical evidence supports a finding, on the balance of probabilities, of injury simpliciter sufficient to satisfy ss 4 and 9A of the 1987 Act.[28] 26. Having found injury simpliciter, I do not need to consider whether the applicant satisfies the disease provisions under s 4(b) of the 1987 Act. However, for the same reasons, I am satisfied that the applicant suffered an aggravation of his underlying degenerative changes in his lumbar spine. Indeed, the evidence indicates that the applicant's back symptoms have been made worse by the 2019 incident contributing to a worsening or intensifying of symptoms in the lumbar spine and this impacted him physically.[29] That is, the applicant's work with the respondent made his condition in the cervical spine "more grave, more grievous or more serious in their effects" on him and employment with the respondent was the main contributing factor to the aggravation.[30]

1. The applicant bears the onus to demonstrate on the balance of probabilities that an injury to the lumbar spine occurred as a result of the 2019 incident. Having regard to the detailed history above I feel an actual persuasion that the applicant suffered an injury to his lumbar spine pursuant s 4(a) and (b) of the 1987 Act.
2. The claim for lump sum compensation pursuant to s 66 of the 1987 Act is remitted to the President for referral to a Medical Assessor in respect of the applicant's injury to his left lower extremity (including scarring) and lumbar spine on 2 March 2019.
3. Accordingly, I make the orders set out above.

[1] Hendrix v Accuro Homecare Pty Ltd [2023] NSWPICPD 48, [86]; MMI Workers Compensation (NSW) Ltd v Kennedy [1993] NSWCC 26; (1993) 9 NSWCCR 482, 489.

[2] Castro v State Transit Authority (NSW) [2019] NSWCCR 496; Rail Services Australia v Dimovski & Anor [2004] NSWCA 267.

[3] Container Terminals Australia Ltd v Huseyin [2008] NSWCA 320, [8] (per Basten JA); Mason v Demasi [2009] NSWCA 227, [2] (per Basten JA).

[4] Nguyen v Cosmopolitan Homes [2008] NSWCA 246, [44] (per McDougall J (McColl and Bell JJA agreeing)); Department of Education and Training v Ireland [2008] NSWWCCPD 134.

[5] Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452; 10 NSWCCR 796.

[6] Badawi v Nexon Asia Pacific Pty Limited t/as Commander Australia Pty Limited NSWCA 324_,_ [80]-[83] (per Allsop P, Beazley and McColl JA; [112]-[117] per Basten JA; [143] per Handley AJA).

[7] Badawi v Nexon Asia Pacific Pty Limited t/as Commander Australia Pty Limited NSWCA 324.

[8] [2004] NSWCA 267.

[9] Castro v State Transit Authority (NSW) [2000] NSWCC 12; 19 NSWCCR 496; Kennedy Cleaning Services Pty Ltd v Petkoska [2000] HCA 45; Military Rehabilitation and Compensation Commission v May [2016] HCA 19; Ky v Blue Leaf Food Group Pty Ltd [2016] NSWWCCPD 55.

[10] Zickar v MGH Plastic Industries Pty Ltd [1996] HCA 31; Rail Services Australia v Dimovski [2004] NSWCA 267.

[11] [2025] NSWPICPD 45, [46].

[12] Rail Services Australia v Dimovski [2004] NSWCA 267, [68].

[13] AV v AW [2020] NSWWCCPD 9, [77]-[78].

[14] [2020] NSWWCCPD 9, [77]-[78].

[15] AV v AW [2020] NSWWCCPD 9, [77]-[78].

[16]Kelly v Western Institute NSW TAFE Commission [2010] NSWWCCPD 71, ([66] per Roche A/President); Federal Broom Co Pty Ltd v Semlitch [1954] HCA 34, [7] (per Windeyer J).

[17] Federal Broom Co Pty Ltd v Semlitch [1954] HCA 34, [9] (per Windeyer J).

[18] Owen v Motor Accidents Authority (NSW) [2012] NSWSC 650, [52] (per Campbell J); Davis v Council of the City of Wagga Wagga [2004] NSWCA 34, [35].

[19] Container Terminals Australia Ltd v Huseyin [2008] NSWCA 320; Mason v Demasi [2009] NSWCA 227, State of New South Wales (Department of Primary Industries v Legrand [2024] NSWPICPD 74.

[20] Military Rehabilitation and Compensation Commission v May [2016] HCA 19; Kennedy Cleaning Services Pty Ltd v Petkoska [2000] HCA 45.

[21] Military Rehabilitation and Compensation Commission v May [2016] HCA 19; Kennedy Cleaning Services Pty Ltd v Petkoska [2000] HCA 45.

[22] North Coast Area Health Service v Felstead [2011] NSWWCCPD 51, [77].

[23] Paric v John Holland (Constructions) Pty Ltd [1985] HCA 58; Makita (Australia) Pty Ltd v Sprowles [2001] NSWCA 305.

[24] Workers Compensation Nominal Insurer v Howard [2011] NSWWCCPD 37, [89]; Hendrix v Accuro Homecare Pty Ltd [2023[ NSWPICPD 48, [85]-[86].

[25] Wallaby Grip (BAE) Pty Ltd v Macleay Area Health Service (1998) 17 NSWCCR 355, [20] (per Beazley JA).

[26] Bugat v Fox [2014] NSWSC 888, [31]-[32], [34].

[27] Owen v Motor Accidents Authority (NSW) [2012] NSWSC 650, [52] (per Campbell J); Davis v Council of the City of Wagga Wagga [2004] NSWCA 34, [35]; Winter v NSW Police Force [2010] NSWCCPD 12, [183].

[28] Nguyen v Cosmopolitan Homes [2008] NSWCA 246, [44] (per McDougall J (McColl and Bell JJA agreeing)); Department of Education and Training v Ireland [2008] NSWWCCPD 134.

[29] Federal Broom Co Pty Ltd v Semlitch [1954] HCA 34; Cant v Catholic Schools Office [2000] NSWCC 37; (2000) 20 NSWCCR 88.

[30] Federal Broom Co Pty Ltd v Semlitch [1994] HCA 34; 110 CLR 626.