Paton Family Trust & Wehttam Holdings Pty Ltd Atf Dobson Trust v Dubois

DETERMINATION OF APPEAL PANEL
CITATION:	Paton Family Trust & Wehttam Holdings Pty Ltd Atf Dobson Trust v Dubois [2023] NSWPICMP 662
APPELLANT:	Paton Family Trust & Wehttam Holdings Pty Limited atf Dobson Trust
RESPONDENT:	Beck Dubois
APPEAL PANEL
MEMBER:	John Wynyard
MEDICAL ASSESSOR:	Mark Burns
MEDICAL ASSESSOR:	Robin Fitzsimons
DATE OF DECISION:	13 December 2023
CATCHWORDS:	WORKERS COMPENSATION - Workplace Injury Management and Workers Compensation Act 1998; appeal by employer from assessment of corticospinal tract impairment; whether asymptomatic pre-existing tumour being made symptomatic should have attracted a section 323 deduction; whether reasons adequate to explain calculations; Held – Medical Assessor (MA) failed to comply with obligation to explain calculations; Chapter 4.11 of the Guides infringed; re-examination accordingly held; MA’s calculations found to be within range; whilst minds might differ, asymptomatic pre-existing tumour contributed to the impairment but determination difficult through lack of evidence section 323(2) applied; Sydney Local Health District v Chan and Wingfoot Australia Partners Pty Ltd v Kocak considered and applied; section 323 authorities acknowledged; Medical Assessment Certificate revoked.

BACKGROUND TO THE APPLICATION TO APPEAL

On 24 May 2023 Paton Family Trust & Wehttam Holdings Pty Limited atf Dobson Trust, the appellant employer, lodged an Application to Appeal Against the Decision of a Medical Assessor. The medical dispute was assessed by Dr Ross Mellick, a Medical Assessor, who issued a Medical Assessment Certificate (MAC) on 28 April 2023.
The appellant relies on the following grounds of appeal under s 327(3) of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act):
· the assessment was made on the basis of incorrect criteria, and
· the MAC contains a demonstrable error.
The delegate is satisfied that, on the face of the application, at least one ground of appeal has been made out. The Appeal Panel has conducted a review of the original medical assessment but limited to the ground(s) of appeal on which the appeal is made.
Rule 128 of the Personal Injury Commission Rules 2021 (the PIC Rules) and Procedural Direction PIC7 - Appeals, reviews, reconsiderations and correction of obvious errors in medical disputes set out the practice and procedure in relation to the medical appeal process under s 328 of the 1998 Act. An Appeal Panel determines its own procedures in accordance with r 128(1) of the PIC Rules.
The assessment of permanent impairment is conducted in accordance with the SIRA NSW Workers Compensation Guidelines for the Evaluation of Permanent Impairment, 4^th ed
1 March 2021 (the Guides) and the American Medical Association Guides to the Evaluation of Permanent Impairment, 5^th ed (AMA 5). “WPI” is reference to whole person impairment.

RELEVANT FACTUAL BACKGROUND

On 8 March 2023, an amended referral was made to the Medical Assessor for an assessment of WPI caused to the nervous system and the cervical spine caused by injury on 4 July 2018.
The Medical Assessor recorded that Mr Dubois was injured whilst working as a formwork carpenter on 4 July 2018 when a large piece of timber struck Mr Dubois on the head, impacting on his hard hat.
He experienced a brief break in continuity of recall for a few seconds and found himself sitting on the concrete floor. He had a sensation of numbness of his whole body and was unable to move his legs for a short period of time.
He was taken to Mona Vale Hospital and scan of his head was performed.
He saw a neurologist about 10 days later, who caused MRI scans of the neck and X-rays of the sternum to be taken on 19 July 2018.
These caused him to see neurosurgeon Dr Asad as a matter of urgency on 27 July 2018.
Mr Dubois was then admitted to Macquarie University Hospital about 10 days after that. He came to surgery on 8 August and 14 August 20 with a diagnosis of a haemangioblastoma which was situated in the cervical cord.
After surgery, Mr Dubois developed numbness and some impairment of function involving the distal left upper extremity and altered sensation from just below the rib cage to the distal lower extremities, with a feeling of numbness and tingling, more severe distally than proximally from the lower rib cage down involving the right leg in particular. His left leg is not as strong as the right.
The Medical Assessor assessed a total of 23% WPI.

PRELIMINARY REVIEW

The Appeal Panel conducted a preliminary review of the original medical assessment in the absence of the parties and in accordance with the Procedural Direction PIC7.
As a result of that preliminary review and the Appeal Panel determined that the worker should undergo a further medical examination, as the issues raised confirmed that a demonstrable error had been made.

VIDENCE

Documentary evidence

The Appeal Panel has before it all the documents that were sent to the Medical Assessor for the original medical assessment and has taken them into account in making this determination.

Further medical examination

Dr Mark Burns of the Appeal Panel conducted an examination of the worker on 27 September 2023 and reported to the Appeal Panel.

Medical Assessment Certificate

The parts of the medical certificate given by the Medical Assessor that are relevant to the appeal are set out, where relevant, in the body of this decision.

SUBMISSIONS

Both parties made written submissions which have been considered by the Appeal Panel.

FINDINGS AND REASONS

The procedures on appeal are contained in s 328 of the 1998 Act. The appeal is to be by way of review of the original medical assessment, but the review is limited to the grounds of appeal on which the appeal is made.
In Campbelltown City Council v Vegan [2006] NSWCA 284 the Court of Appeal held that the Appeal Panel is obliged to give reasons. Where there are disputes of fact it may be necessary to refer to evidence or other material on which findings are based, but the extent to which this is necessary will vary from case to case. Where more than one conclusion is open, it will be necessary to explain why one conclusion is preferred. On the other hand, the reasons need not be extensive or provide a detailed explanation of the criteria applied by the medical professionals in reaching a professional judgement.

THE MAC

In his summary, the Medical Assessor said at [7]:
“Mr Dubois had a haemangioblastoma involving the upper cervical cord prior to the injury in question. The trauma clearly resulted in the asymptomatic lesion becoming symptomatic resulting in the subsequent surgery and the abnormalities currently identified.”
In giving his reasons for assessment at [10a] of the MAC, the Medical Assessor said:
“In making that assessment I have taken account of the following matters:-
The history obtained by me, my findings on physical examination and a consideration of the results of investigations and other documentary evidence.
b. An explanation of my calculations (if applicable)
No calculations applicable.”
At [10c] the Medical Assessor said, in discussing the opinions of other experts:[1]
“Mr Dubois has been seen by Dr Dudley O’Sullivan, neurologist, who has prepared two reports dated 19 December 2021 and 6 January 2022….
Dr O’Sullivan’s second report excluded impairments associated with the myelopathy from the whole person impairment, writing ‘his present neurological impairment relates to the presence of the tumour and the subsequent surgery as documented in my report. Therefore, on the basis of Section 323 of the 1998 Act, I would have to consider that his degree of whole person impairment as a result of the injury at work would have been soft tissue muscle and ligamentous injury with non-verifiable radicular symptoms which would equate to a DRE Category II ...5.0% WPI’.
The history provided to me by Mr Dubois is that the impact caused him to be knocked to the concrete floor. He was immediately aware of numbness involving his ‘whole body’ for a short time with impairment of lower extremity function so that he was not able to get to his feet and walk. He also experienced pain in the region of the left shoulder and left collarbone yet there was no impact on the shoulder or collar bone.
The symptoms at impact indicate that the injury resulted in symptoms of acute myelopathy resulting in the impairment of lower limb function and the altered sensation of his trunk and impairment of lower extremity function.
I respectfully disagree with Dr O’Sullivan’s assessment. The injury that occurred on 4 July 2018 was associated with occurrence of symptoms of weakness in the lower limbs and an MRI scan revealed cervical heamangioblastoma [sic]. The scan showed ‘high grade oedema within the cord extending distally to the anatomical site of the tumour’.
The preexisting haemangioblastoma, was accordingly rendered symptomatic when the injury occurred as indicated by the MRI scans….
The radiological findings are reported by Dr O’Sullivan and provide evidence that the injury caused acute demonstrable effects on the tumour which had been asymptomatic up until that time. A direct consequence of the injury in question was the necessity for surgery to be done, a necessity that did not exist prior to the injury in question. The neurological abnormality involving corticospinal function described by Dr O’Sullivan arose because of the urgent need for neurosurgical attention to the tumour. The surgery performed by Dr Ahmed was an urgent requirement because of the magnitude of oedema and the potential threat of paraplegia or perhaps impairment of respiratory function which might have been life-threatening.”
[1] Appeal papers page 33.
On the same page and following, the Medical Assessor said:
“Although the pre-existing presence of the tumour prior to the injury represented the predisposition or a vulnerability, it was the injury itself that produced symptoms and signs of myelopathy and the need for the urgent surgery that followed and the neurological deficit now present.”

SUBMISSIONS

The appellant employer submitted that the Medical Assessor had not complied with Chapter 4.11 of the Guides. We were referred to Vannini v Worldwide Demolitions Limited[2] in furtherance of its submission that it was not possible to understand the actual path of reasoning by which the Medical Assessor arrived at his assessments.
[2] [2018] NSWCA 324.
The appellant employer also submitted that the Medical Assessor had not properly applied the provisions of Chapter 1.28 of the Guides and had thus infringed the provisions of s 323 of the 1998 Act.
The appellant employer submitted that the tumour discovered following the injury, although asymptomatic, had contributed to the degree of permanent impairment assessed for the subject injury.
We were referred to a number of well-known cases regarding the section.[3]
[3] Vitaz v Westform NSW Pty Ltd [2011] NSWCA 254; ElCheikh v Diamond Formwork (NSW) Pty Ltd (in liquidation) [2013] NSW SC 365; Ryder v Sundance Bakehouse [2015] NSWSC 526.
The appellant employer recited the facts and submitted that there could be “no doubt” that there was a pre-existing condition or abnormality that did contribute to the degree of permanent impairment. The size of the tumour in its position in reference to the spinal cord it was submitted, would justify a deduction of 80% from the impairment caused by the subject injury.

Respondent

Mr Dubois (the respondent) submitted that argument advanced by the appellant employer was no more than a mere disagreement with the assessment undertaken by the Medical Assessor.
As to the submission that the reasons were not adequately explained Mr Dubois submitted that the actual path of reasoning started with recording the steps that were in fact taken in arriving at the end result.
We referred to the well-known dicta of Handley AJA in Bojko v ICM Property Service PTY Limited.[4]
[4] [2009] NSWCA 175.
It was submitted that the reasons need not be extensive or provided detail an explanation of the criteria applied by medical specialists in reaching a professional judgement.
Mr Dubois then referred to the well-known definitions of demonstrable error and incorrect criteria as considered in a number of cases.[5]
[5] Merza v Registrar Workers Compensation Commission [2006] NSWSC 939; Haroun v Rail Corporation NSW [2008] NSWSC 160; Marina Pitsonis (incorrectly cited) v the Workers' Compensation Commission [2008] NSWCA 88 and Vegan (cited at the outset of these reasons).
It was submitted that the appellant employer had failed to demonstrate error or the application of incorrect criteria. We were referred to the Medical Assessor’s reasons regarding his decision not to apply the terms of s 323.
It was submitted that the Medical Assessor's reasons were clear and that the appellant employer had failed to demonstrate any error in that regard.
With regard to the ground that the Medical Assessor’s path of reasoning was not disclosed, we were referred to the history taken by the Medical Assessor and the symptoms that Mr Dubois was presently suffering.
Mr Dubois appears to have substituted a “Dr Anderson AMS” in his submissions at [23]-[24], but nonetheless submitted that the Medical Assessor had provided a detailed analysis of the medical-legal advice given by Dr O’Sullivan and explained why he disagreed with that specialist's assessment.
It was submitted that if one reviewed the tables referred to the findings and explanation of the Medical Assessor became clear.
Mr Dubois emphasised that the authorities made it plain that the reasons were not to be reviewed with a fine-tooth comb for error.
With regard to error alleged regarding the assessment by the Medical Assessor and the provisions of s 323, we were referred to in the Guides at Chapters 1.16(a), 1.27 and 1.28. Mr Dubois kindly reproduced s 323 in his submissions.
We were then referred to further well-known and uncontroversial cases regarding the application of the section, which were also relied upon by the appellant employer.[6]
[6] Cole v Wenaline Pty Ltd [2010] NSWSC 78; Ryder v Sundance Bakehouse [2015] NSWSC 526 and Vitaz v Westform NSW Pty Ltd [2011] NSWCA 254.
Mr Dubois submitted that the mere existence of the tumour at the time of the injury did not per se mean that a deduction should be made for its presence.
The above authorities mandated that if a pre-existing condition were identified that there also had to be an impairment caused by that pre-existing condition for it to enliven the provisions of s 323.
We were referred to various parts of the Medical Assessor's opinion, which we have reproduced above. It was submitted that those references made it plain that no such deduction was required.

DISCUSSION

We found, with respect, the reporting by the Medical Assessor to be somewhat cryptic. A Medical Assessor, as much as a Medical Appeal Panel, is required to set out in a statement of reasons the actual path of reasoning by which he arrived at his opinion.[7]
[7] Sydney Local Health District v Chan [2015] NSW SC 1968 at [13] citing Wingfoot Australia Partners Pty Ltd v Kocak [2013] HCA 43 at [48].
It is also relevant to consider, as we indicated above in Vegan, that the reasons do not have to provide a detailed explanation of the criteria applied by medical professionals in reaching a professional judgement. In other words, it must be borne in mind that the majority of a Medical Appeal Panel is constituted by medical professionals in the same discipline as the Medical Assessor, who may be presumed to understand the more esoteric aspects of the reasons under consideration.
However, there has to be a balance between such specialisation, and the ability of the parties to understand the basis of the decision, and this balance has not been adequately kept in the present case.
The Medical Assessor’s statement that “no calculations applicable” was in answer to the templated heading “An explanation of my calculations (if applicable).” It can thus be seen that the Medical Assessor was answering the templated question but made an error in saying that there were no applicable calculations.
The Medical Assessor was also under a duty to explain the calculations by virtue of the provisions of Chapter 4.11 of the Guides, Chapter 4 being headed “The Spine”:
“4.11 The assessor should include in the report a description of how the impairment rating was calculated, with reference to the relevant tables and figures used.”
The applicable calculations were referred to by the Medical Assessor in his Table 2 certificate.[8] They consisted of Chapter 4.33 and 4.34 of the Guides, and Chapter 15, Table 15-5 of AMA 5 in respect of the assessment of the nervous system, and Chapter 4.7, 4.18. 4.33 and 4.34 of the Guides and Chapter 15, Table 15-6a and 15-6c of AMA 5 for the cervical spine. The calculations are made by a consultation of the criteria set out in
[8] Appeal papers page 35.
Table 15-6.
Table 15-6 provides:[9]
Table 15-6 Rating Corticospinal Tract Impairment
[9] AMA5 page 396.

a. Impairment of One Upper Extremity Due to Corticospinal Tract Impairment
Class 1		Class 2		Class 3		Class 4
Dominant Extremity 1%-9% Impairment of the Whole Person	Nondominant Extremity 1%-4% Impairment of the Whole Person	Dominant Extremity 10%-24% Impairment of the Whole Person	Nondominant Extremity 5%-14% Impairment of the Whole Person	Dominant Extremity 25%-39% Impairment of the Whole Person	Nondominant Extremity 15%-29% Impairment of the Whole Person	Dominant Extremity 40%-60% Impairment of the Whole Person	Nondominant Extremity 30%-45% Impairment of the Whole Person
Individual can use the involved extremity for self-care, daily activities, and holding, but has difficulty with digital dexterity		Individual can use the involved extremity for self-care, can grasp and hold objects with difficulty, but has no digital dexterity		Individual can use the involved extremity but has difficulty with self-care activities		Individual cannot use the involved extremity for self-care or daily activities
b. Criteria for Rating Impairments of Two Upper Extremities
Class 1 1%-19% Impairment of the Whole Person		Class 2 20%-39% Impairment of the Whole Person		Class 3 40%-79% Impairment of the Whole Person		Class 4 80%+ Impairment of the Whole Person
Individual can use both upper extremities for self-care, grasping, and holding, but has difficulty with digital dexterity		Individual can use both upper extremities for self-care, can grasp and hold objects with difficulty, but has no digital dexterity		Individual can use both upper extremities but has difficulty with self-care activities		Individual cannot use upper extremities
c. Criteria for Rating Impairments Due to Station and Gait Disorders
Class 1 1%-9% Impairment of the Whole Person		Class 2 10%-19% Impairment of the Whole Person		Class 3 20%-39% Impairment of the Whole Person		Class 4 40%-60% Impairment of the Whole Person
Rises to standing position; walks, but has difficulty with elevations, grades, stairs, deep chairs, and long distances		Rises to standing position; walks some distance with difficulty and without assistance, but is limited to level surfaces		Rises and maintains standing position with difficulty; cannot walk without assistance		Cannot stand without help, mechanical support, and/or an assistive device

It may well be that the Medical Assessor assumed that the Table 2 certificate information was sufficient compliance with Chapter 4.11, but whilst he thus identified the relevant guidelines, he did not explain how they were applied in the calculation of the assessment arrived at. Whilst medical professionals might be able to infer how he had applied them, there is some substance in the appellant employer’s submission that it could not follow the Medical Assessor’s path of reasoning as to how he arrived at the actual figures assessed.

Accordingly, we arranged for Mr Dubois to be re-examined. Dr Burns’ report on re-examination follows:

“PERSONAL INJURY COMMISSION

APPEAL AGAINST MEDICAL ASSESSMENT

REPORT OF THE EXAMINATION BY MEDICAL ASSESSOR

MEMBER OF THE APPEAL PANEL

Matter Number:	M1-W8000/22
Appellant:	Paton Family Trust & Wehttam Holdings Pty Ltd Atf Dobson Trust
Respondent:	Beck Dubois
Date of Determination:	22 June 2023

Examination Conducted By:

Assessor Mark Burns

Date of Examination:

Attendance:

27 September 2023

Beck Dubois

1. The workers medical history, where it differs from previous records
Mr Dubois confirmed the history taken by Assessor Mellick on 13 April 2023.
2. Additional history since the original Medical Assessment Certificate was performed
Mr Dubois reported that there has been no change over the last 6 months. He has had no further treatment since that period and his next appointment to see the Neurosurgeon is in February 2024.
3. Findings on clinical examination
Current symptoms:
Mr Dubois reported that he continues to have impairment of function of his left arm below the elbow, including the hand. In this area there is decreased sensation as well as weakness. He lacks manual dexterity in his left hand and reported that he often drops items. He reported today that he also has occasional symptoms in his right arm, but these are not giving him any functional disability.
He reported that he continues to have difficulty with proprioception with altered sensation to superficial touch in both the right and left legs. He reported that his gait is reasonable, but he can have difficulty in knowing the position of his feet. He does not use assistive aids but does have problems with inclines and stairs. He needs to look down to check the position of his feet and to use handrails.
He continues to work as a form work carpenter doing 32 hours per week. He reports that the work he has been given is far less demanding than that he was carrying out before his injury.
Current treatment:
He is taking no medication at the current time, and he is having no formalised treatment. He is due to see his Neurosurgeon in February 2024 for routine follow up. This will include several investigations.

Activities of daily living:
I discussed with Mr Dubois how his cervical spine cord injury impacts on his activities of daily living. I note that the activities are listed in Table 1-2 of the 5^th Edition of the AMA Guides.
§    Self-care and personal hygiene: He reports that he has no impact from his spinal cord injury.
§    Communication: His lack of manual dexterity and a degree of weakness in his left hand impacts his ability to type or text. As he is right hand dominant it does not impact upon his writing.
§    Physical activity: He reported that prolonged sitting on a hard chair tends to give him discomfort especially around the region of his hips. He also reported that he finds walking over prolonged distances difficult. He is much slower going up and downstairs than he had been previously and due to the lack of sensation and proprioception in his feet he now must watch where he walks, especially going up and down stairs. Occasionally he is unable to ascend or descend stairs or inclines
§    Sensory function: His spinal cord injury has left him with decreased feeling in the left hand as well as weakness. His manual dexterity has decreased, and he often drops items. He reported that he also has a degree of hypersensitivity in the area below the navel going down into both legs.
§    Non-specialised hand activities: Hand function on the right side was reasonably well preserved. On the left side he noted decrease in dexterity and grip strength was measured at today’s consultation using a Dynamometer. On the right side it was 44kgs, which is within the normal range but on the left side it was only 20kgs. Because of the weakness and lack of sensory input from the left hand he tends to lift items with both hands.
§    Travel: Due to the lack of sensory input from the left hand as well as weakness he changed from driving a manual car to an automatic car. Another reason for changing to an automatic car was the fact that he did not trust his feet upon the clutch in the manual vehicle. He now drives but only travels short distances.
§    Sexual function: He reported that he has no functional problems with his sexual activity.
§    Sleep: He stated that the main difficulty with sleeping is often neck pain if his head and neck are in a bad position. Apart from this his sleep is not particularly impacted upon.
4. Results of any additional investigations since the original Medical
Assessment Certificate
He reported that he has had no investigations carried out since he was seen by Assessor Mellick.
5. My comments
I noted that the physical examination findings of the Medical Assessor had not been challenged in the appeal. At re-examination I confirmed the findings of Assessor Mellick with respect to his physical examination.
From Table 15-6(a) the impairment of his upper non-dominant arm can be assessed due to his corticospinal tract injury. He can use his non-dominant arm for most activities of self-care but does have a decrease in dexterity and strength, which impacts upon his ability to hold items. I believe he would fall into Class 1 from this Table and considering his activities of daily living impact he would be at the top end of Class 1, which would be 4% whole person impairment.
From Table 15-6 (c) dealing with Station and Gait Disorders, I note that he was able to rise to the standing position from a chair and was able to walk across the examination room with only a mild alteration in gait. He tended to walk slowly and look at the position of his feet. He stated that he did have difficulty in going up and down stairs and quite often would need to use the handrail as well as watching his feet as he is not getting adequate proprioception. He reported that he is not able to walk long distances and has difficulty with inclines and stairs. He tires quickly with walking, especially with inclines and stairs. Even though he reported difficulty with inclines and stairs he is only partially limited to level surfaces. With respect to whether he is in Class 1 or Class 2, I believe that he fulfils criteria for both Classes with the one exception being not always limited to level surfaces in Class 2.Taking account of his activities of daily living I believe that the mid-range of Class 2 would be appropriate. Certainly the 15% decided by Assessor Mellick would not be outside this range.
With respect to the s323 deduction, I believe that the severity of the injury was probably sufficient to cause the spinal cord injury irrespective of the presence of the haemangioblastoma. This was a relatively slow growing tumour and at the time of injury asymptomatic. I am not convinced that the presence of the tumour contributed significantly to the impairment caused by the actual injury but the presence of the tumour would have led to a minor exacerbation of the tumour swelling thus increasing the impairment outcome.”

We adopt the findings by Dr Burns. Accordingly, the Medical Assessor’s calculations regarding the nervous system impairment rating have been shown to have been properly based on the relevant tables and figures he certified in his Table 2 Certificate.
Section 323 of the 1998 Act provides relevantly:
“(1) In assessing the degree of permanent impairment resulting from an injury, there is to be a deduction for any proportion of the impairment that is due to any previous injury (whether or not it is an injury for which compensation has been paid or is payable under Division 4 of Part 3 of the 1987 Act) or that is due to any pre-existing condition or abnormality.
(2) If the extent of a deduction under this section (or a part of it) will be difficult or costly to determine (because, for example, of the absence of medical evidence), it is to be assumed (for the purpose of avoiding disputation) that the deduction (or the relevant part of it) is 10% of the impairment, unless this assumption is at odds with the available evidence.”
As we indicated, the authorities in this area of law are well known and uncontroversial. As submitted by the appellant employer, the application of the section requires a three-step approach:
“Firstly, establishing what the extent of the resulting impairment is from the subject injury.
Secondly, enquiring whether the pre-existing condition contributed to the impairment.
Thirdly, if it did, calculating what proportion of the impairment was due to the pre-existing condition.”
Mr Dubois’s haemangioblastoma was undoubtedly asymptomatic prior to the subject injury, and accordingly the decision of the Court of Appeal in Vitaz is apposite. The often-quoted dicta of Basten JA (McColl JA and Handley AJA agreeing) appears at [43]:
“…The resulting principle is that if a pre-existing condition is a contributing factor causing permanent impairment, a deduction is required even though the pre-existing condition had been asymptomatic prior to the injury. In the absence of any medical evidence establishing a contest as to whether the pre-existing condition did contribute to the level of impairment, the complaint about a failure to give reasons must fail. An approved medical specialist is entitled to reach conclusions, no doubt partly on an intuitive basis, and no reasons are required in circumstances where the alternative conclusion is not presented by the evidence and is not shown to be necessarily available.”
In Mr Dubois’ case an alternative conclusion was clearly available, as was explained by the Panel’s Dr Burns. The appellant employers’ submissions were reflected in the opinions of its medico-legal advisor, Dr O’Sullivan, Neurologist, whose first report of 3 December 2021 stated:[10]
“The diagnosis is that of a haemangioblastoma in the cervical cord at the level of C 2. There is no doubt that this condition was asymptomatic prior to the injury that occurred at work on 4 July 2018 but the impact of that injury resulted in the patient’s haemangioblastoma becoming symptomatic especially with regard to the swelling of the cervical cord with significant oedema. Therefore the presence of this tumour was made symptomatic by the injury that occurred.
…..
There would be no doubt that he would have had pre-existing haemangioblastoma in the cervical cord which of course was totally asymptomatic prior to his injury at work. Therefore the accident aggravated the pre-existing condition namely the haemangioblastoma. It is clear that the injury caused swelling of that particular tumour resulting in him having his surgical procedure required.”
[10] Appeal papers page 79.
In assessing the impairment caused by the subject injury, Dr O’Sullivan said:[11]
“Using the Combined Tables I have combined the 20% due to his left upper limb impairment with the 9% due to his gait disturbance and this equals to 27% whole person impairment. However, in my opinion if he did not have the tumour, he would have only sustained soft tissue injury to his central spine and so I will deduct 10% due to the presence of the tumour. Finally, therefore, he has 24%.”
[11] Appeal papers page 80.
In his next report dated 19 December 2021, Dr O’Sullivan amended his opinion to advise that Mr Dubois would in fact have suffered a 22% WPI. We had some difficulty in following Dr O’Sullivan’s reasoning for making such an alteration, with respect.
Dr O’Sullivan provided a further report dated 6 January 2022, in answer to a request for clarification. He said:
“It is clear from my previous report that [Mr Dubois’s] degree of whole person impairment relates to the pre-existing tumour and subsequent surgery. His present neurological impairment relates to the presence of the tumour and subsequent surgery as documented in my report. Therefore on the basis of section 323 of the 1998 Act I would have to conclude that his degree of whole person impairment as a result of the injury at work would have been soft tissue muscle and ligamentous injury with non-verifiable radicular symptoms which would equate to a DRE category II and this therefore would make the assessment of whole person impairment as a result of his work injury at 5%.
The 27% whole person impairment that I made previously is as a consequence of him having the tumour and requiring the subsequent surgery. As stated, the degree of whole person impairment that I have concluded relates to the presence of the tumour in the requiring of subsequent surgery and not precisely to the beam which fell on his head and caused the tumour to become symptomatic.”
The Medical Assessor considered this opinion, as we have indicated above, but some more factual detail needs to be recorded as to the factual circumstances. The Medical Assessor stated, as indicated, that “a large piece of timber struck Mr Dubois on the head, impacting his hard hat”.
Mr Dubois’ description in his statement of 14 February 2022 was:[12]
“10. A piece of timber measuring 360 x 150 x 100 millimetres, weighing approximately 20kgs fell about 2 and a half metres high and hit me on the head. I was looking up at the moment of impact and beam landed on my forehead.”
[12] Appeal papers page 46.
This history was repeated by Dr Paul Teychenne with some more detail:[13]
“The patient sustained an injury on the 4^th July 2018 at 10am. He was working as a carpenter wearing a helmet when a large piece of timber 3.6m long x 150mm wide and 100mm deep weighing about 20kgs fell about 2 ½ metres. He was looking up at the moment of impact. The beam hit him over the forehead. His head was acutely jerked back. He had a laceration over the mid-upper lip. His hard hat was knocked off. He recalled the bang and then he lost memory. Apparently he was amnesic for 3 seconds. He was in a sitting position when it happened.”
[13] Appeal papers page 59.
Dr O’Sullivan recorded:[14]
“As documented the injury occurred at work on 4 July 2018. He was struck on his head by a falling beam. It fell approximately 3 metres which weighed around 40kg. The beam struck his forehead and face and he landed on the ground and was momentarily knocked unconscious. In fact he said that when he hit the ground he was sitting up. He recalls telling another workmate that he couldn’t feel anything below his neck. This impaired sensation lasted a few seconds and then the sensation returned.”
[14] Appeal papers page 1,108.
It can be seen that there is some consistency in the accounts of the injury – except that Dr O’Sullivan thought the beam weighed 40kg.
We note the evolving assessments by Dr O’Sullivan. It is apparent from his first report
(3 December 2021) that he considered a 10% deduction to be appropriate, having found that the accident aggravated Mr Dubois’s asymptomatic pre-existing tumour. Dr O’Sullivan stated that “it was clear” that the injury caused swelling of the tumour “with significant oedema” which resulted in the surgical procedures to remove it.
We consider that approach to be reasonable, noting the terms of s 323(2) that provide that where the extent of the deduction would be, relevantly, difficult to determine a 10% deduction is to be made, unless it is at odds with the available evidence.
Dr O’Sullivan described the findings of the MRI scan taken on 19 July 2018. He said:[15]
“…this revealed the presence of a hemangioblastoma measuring 25x15x12mm as a multilocular cystic mass in the upper cervical cord behind the C2 vertebral body. The CSF is completely effaced by the mass. There is high grade oedema extending within the cord distal to the mass to the level of C6…”
[15] Appeal papers page 76.
Thus the tumour was discovered at the C2 level of the spine, but the oedema extended from that level to the C6 level. We find it difficult to determine whether the full extent of the oedema was the result of the aggravation of Mr Dubois’ tumour. The nature of a hemangioblastoma is that it is a slow growing, vascular disease, which can be associated with oedema. However, there was no objective evidence to confirm that the oedema extending down to C6 was as a result of the aggravation to the tumour by the falling beam. The C2 area of the spine was not directly impacted, but was rather made symptomatic through being hyperextended as Mr Dubois’ head was forced backward when the beam hit his forehead. It is reasonable to postulate that the force of the blow may have caused some oedema at the site of the tumour, but to find that the aggravation to the tumour caused all the oedema found on the MRI we find to be speculative.
Thus we have some difficulty, with respect, in accepting Dr O’Sullivan’s revised opinion
(6 January 2022) that the whole of Mr Dubois’ impairment was as a result of this aggravation.
We make the same observation as to the opinion of Dr Assad, the treating Neurosurgeon, who reported on 8 August 2022 that the spinal cord symptoms were “secondary to oedema surrounding an underlying spinal cord tumour” Dr Assad’s priority was resecting the tumour, and whilst he associated all the spinal symptoms with oedema, he did not consider whether the force of the contact of the beam when it hyperextended Mr Dubois’ neck would of itself have precipitated spinal cord dysfunction with symptoms of oedema.[16]
[16] Appeal papers page 56.
The Medical Assessor’s reasoning as to this aspect of the case was somewhat ambiguous. Whilst he acknowledged that the tumour was described by Dr Assad and in Dr O’Sullivan’s second report as requiring surgery “because of the magnitude of the oedema” he did not make any further relevant comment as to the cause of the oedema, simply noting that the surgery was urgent because there was a potential threat of paraplegia or respiratory failure.
We note that the Medical Assessor was incorrect to describe the asymptomatic tumour as a “vulnerability”, as a hemangioblastoma is a diagnosable and established clinical entity, and thus falls within the definition of “pre-existing condition” contained in s 323(1).[17] He did not, with respect, give adequate reasons as to why no deduction was applicable, and the thrust of his reasons appeared to implicate the pre-existing tumour as being a factor in the impairment caused by the subject injury. Inasmuch as his reasons may imply that the whole or most of Mr Dubois’ condition was due to the hemangioblastoma, we disagree for the reasons given.
[17]Fire & Rescue NSW v Clinen [2013] NSWSC 629 per Campbell J at [34 – 35].
The discovery of the hemangioblastoma was a fortunate side effect of the injury, in that Mr Dubois was made aware of it by the blow to his head. After reviewing the evidence and re-examining Mr Dubois we are of the view that the presence of the tumour, which was undetected until the MRI scan of 19 July 2018, has diverted the attention of Dr Assad and Dr O’Sullivan from the significance of the force of the actual blow caused by a beam of up to 40kg falling a distance of two and a half to three metres onto Mr Dubois’ forehead. The impairment found by both the Medical Assessor and Dr Burns of the Medical Appeal Panel is consistent with what might be expected from such an injury.
For these reasons, the Appeal Panel has determined that the MAC issued on 28 April 2023 should be revoked and a new MAC should be issued. The new certificate is attached to this statement of reasons.

WORKERS COMPENSATION DIVISION

APPEAL PANEL

MEDICAL ASSESSMENT CERTIFICATE

Injuries received after 1 January 2002

Matter number:	W8000/22
Applicant:	Paton Family Trust & Wehttam Holdings Pty Limited atf Dobson Trust
Respondent:	Beck Dubois

This Certificate is issued pursuant to s 328(5) of the Workplace Injury Management and Workers Compensation Act1998.

The Appeal Panel revokes the Medical Assessment Certificate of Medical Assessor Dr Ross Mellick, and issues this new Medical Assessment Certificate as to the matters set out in the table below:

Table - whole person impairment (WPI)

Body Part or system	Date of Injury	Chapter, page and paragraph number in NSW workers compensation guidelines	Chapter, page, paragraph, figure and table numbers in AMA5 Guides	% WPI	WPI deductions pursuant to S323 for pre- existing injury, condition or abnormality (expressed as a fraction)	Sub- total/s % WPI (after any deductions in column 6)
Nervous	4/7/18	Chapter 4	Chapter 15
System	p 24	p 373
Cortico- spinal	Pars 4.7, 4.18,	Table 15-6a	4.0%	10%	4.0%
4.33, 4.34 (ADL)	15-6c	15.0%	10%	14.0%
Cervical Spine	4//.18	Chapter 4 Pars 4.33 4.34 (ADL)	Chapter 15 p 392 Table 15-5	5.0% 1.0%	0	6%
Total % WPI (the Combined Table values of all sub-totals)					22.0%

[2023] NSWPICMP 662

13 December 2023