Mifsud v Pitador Excavations Pty Limited t/as JD Concrete Pty Ltd

Background facts

1. In or around September 2014, Mr Mifsud was undertaking his work as a concreter for the employer when he experienced symptoms in his right shoulder while exerting effort and strain to extract a peg from the ground. On 25 March 2015, while trowelling and smoothing out concrete he developed further significant pain in his right shoulder which caused him to cease work.
2. He underwent shoulder surgery in May 2015, which did not result in any improvement. He suffered ongoing pain around his right shoulder with symptoms spreading down his arm. Further investigations post-operatively did not reveal any obvious source for the pain, and no abnormality was revealed through imaging of the cervical spine.
3. Mr Mifsud was then reviewed by two separate pain specialists, who diagnosed him as suffering from CRPS. He has undergone interventional treatment in the form of stellate ganglion blocks and a rehabilitation program, which has not resulted in any significant improvement.
4. There was no dispute between the parties that Mr Mifsud suffered a degree of WPI referable to the frank injury to his right shoulder. Indeed, a "complying agreement" under s 66A WCA in respect of a degree of permanent impairment of 12% was entered into on 13 June 2017.
5. The claim for a reassessment of the degree of WPI suffered by Mr Mifsud for the purpose of overcoming the limitation in his entitlement to weekly payments was based upon a report of Associate Professor T W Boesel, a pain medicine physician and specialist anaesthetist, dated 3 March 2020. A/Prof Boesel assessed a 45% impairment of the right upper extremity equating to a 27% WPI. A/Prof Boesel, like the AMS, found "loss of motion impairments" affecting Mr Mifsud's elbow and wrist as well as his shoulder (Court Book pp. 182 - 183 ("CB")). It is also quite clear that A/Prof Boesel related these impairments to CRPS Type 2 of Mr Mifsud's right arm "following arthroscopic shoulder surgery that was performed to treat his workplace injury" (CB p. 184). He regarded the history of injury and medical history as "indicative of an initial labral tear of the right shoulder sustained from an excessive shoulder traction incident and the subsequent development of a large labral cyst and completion of the tear" due to the ongoing performance of demanding physical work. The CRPS Type 2 "is a complication of his corrective procedure" ie, the surgery. A/Prof Boesel opined that Mr Mifsud "has a complex pattern of nerve injury that is probably attributable to intra-operative positioning and traction placed on the limb to facilitate" his previous shoulder surgery (CB p. 184). Neither A/Prof Boesel or any other medical referee whose report was relied upon by Mr Mifsud posited any other hypothesis connecting Mr Mifsud's elbow and wrist impairments with the frank shoulder injury.
6. Professor William Cumming, orthopaedic surgeon, who assessed Mr Mifsud on behalf of the employer, regarded the range of movement of Mr Mifsud's elbow as normal but found a significant limitation in the range of movement in his wrist and fingers (CB p. 418). In his report of 11 August 2021, while acknowledging A/Prof Boesel's expertise, Professor Cumming disputed the diagnosis of CRPS as he felt on the basis of his examination the clinical criteria established by Chapter 17 of the New South Wales Workers Compensation Guidelines for the Evaluation of Permanent Impairment (Fourth Edition) ("SIRA guidelines") enabling a diagnosis of CRPS to be made were not satisfied. Professor Cumming did not question the genuineness of Mr Mifsud's presentation but suggested that the impairment affecting Mr Mifsud's wrist and fingers may well be due to irritative carpal tunnel syndrome which, if that alternative diagnosis was correct, could well be greatly improved by "effective carpal tunnel release" surgery (CB p. 420). Although Professor Cumming's findings on examination did not satisfy the Chapter 17 criteria, he was of the view that Mr Mifsud "may well have what is described as complex regional pain syndrome" (CB p. 419). Professor Cumming did not express any firm conclusion as to the cause of any carpal tunnel syndrome from which Mr Mifsud may suffer. He did record (and seemed to accept) that the more extensive symptoms had arisen immediately following surgery and stated (CB p. 414): "[in] my opinion, Mr Mifsud could well be one of the unusual cases of this irritative carpal tunnel syndrome, although I have no explanation nor is there usually an explanation as to why the carpal tunnel would be involved." Given the uncertainties about the aetiology of Mr Mifsud's condition and the prognosis, Professor Cumming did not assess the degree of WPI.

Medical assessment

1. This question of the degree of WPI was originally referred by the Registrar's delegate for assessment under s 319 WIM on 13 October 2020 and was issued first to the parties for their consideration. The wording of the original referral was the subject of email communication between the parties, resulting in an amended referral being agreed and issued to the AMS on 16 October 2020. The amended referral was as follows (at CB p. 100): "Right upper extremity (right shoulder, right elbow, right wrist and peripheral nerves - as a result of CRPS Type 2 (if present))."
2. The AMS to whom the matter was referred for assessment was Dr Rob Kuru, an orthopaedic surgeon. The AMS carried out his assessment on 23 October 2020, and the MAC was issued on 29 October 2020. The AMS summarised Mr Mifsud's injuries and diagnoses at CB p. 75: "It would appear at the time of the [injury] that Mr Mifsud developed a labral tear and subsequently went on to develop a perilabral cyst. Unfortunately, surgical correction of this has not been associated with improvement in his symptoms and he has gone on to develop a variety of other symptoms which are difficult to explain. Whilst these symptoms have led to a diagnosis of chronic regional pain syndrome, I have not been able to confirm this in my clinical assessment today."
3. As I have said already, the AMS assessed Mr Mifsud's WPI as 13%. This assessment was solely based upon the impairment of Mr Mifsud's right upper extremity (shoulder). In explaining his calculations, the AMS identified the critical issue as being "… whether Mr Mifsud does or does not satisfy the diagnostic criteria for complex regional pain syndrome Types 1 and 2 in Table 17.1 of the SIRA Guidelines, page 81." (CB p. 76). The AMS further stated (CB p. 76): "… the SIRA Guidelines page 81, Table 17.1 paragraph 3 states that "At least one sign at time of evaluation in all of the following categories" must be present and further it goes on to state that "A sign is included only if it is observed and documented at the time of the impairment evaluation". At the time of my assessment I did not observe any vasomotor changes defined as "Evidence of temperature asymmetry and / or asymmetric skin colour changes", nor did I identify sudomotor or oedema, defined as "Evidence of oedema and / or sweating asymmetry". Hence, I am unable to make the diagnosis according to Table 17.21 [sic]." As a result of this, the AMS did not proceed to assess the impairment referrable to the restricted range of motion of the elbow and wrist. He calculated the WPI by reference to shoulder impairment only.

Appeal under ss 327 and 328 WIM

1. By written application in the prescribed form, Mr Mifsud's solicitors applied to the Registrar to appeal from the AMS's decision under s 327 WIM on the grounds that, first, the assessment was made on the basis of incorrect criteria, and, secondly, the MAC contained a demonstrable error: subss 327(3)(c) - (d) WIM. From the written submissions forming part of the application, it is apparent the proposed appeal was on the ground that the AMS had failed to make an assessment of impairment of the right elbow and right wrist, despite the apparently clear findings of loss of range of movement, such failure constituting an application of incorrect criteria and a demonstrable error (CB p. 86).
2. The employer opposed the appeal, submitting (at CB p. 92): "… in the absence of a diagnosis of CRPS the AMS correctly assessed the underlying diagnosed condition and accepted injury to the right shoulder only and that there was no basis to assess impairment of the right elbow or wrist."

The medical appeal

1. The Appeal Panel was constituted by a non-presidential member of PIC, Mr John Wynyard, and two approved medical assessors, Dr Roger Pillemer and Dr David Crocker. Its first written decision was given on 10 March 2021. In addition to determining that the MAC issued on 29 October 2020 should be confirmed, it made the following findings: "The amended referral issued on 16 October 2020 failed to include a request for the assessment of WPI caused by personal injury to the right shoulder on 23 March 2015. It was agreed by the respondent that such an assessment had been intended." The Appeal Panel requested the provision of an amended referral to correct what it regarded as an important omission, which was the subject of its second decision, as I have already said.
2. The appeal was "heard" on the papers and without any oral hearing. Mr Mifsud did not seek to be re-examined by a medical member of the Appeal Panel, and re-examination did not occur as it was not found to be necessary by the Appeal Panel.
3. The Appeal Panel's reasons for finding the amended referral deficient, and confirming the MAC are set out at CB pp. 103 - 106 ([41] - [64]). Regarding the referral, the Panel remarked (at CB p. 103 [46]): "The form of the referral was regrettable. It was potentially misleading and confusing, as it failed to include the right shoulder injury, liability for which had been accepted, as evidenced by the complying agreement of 13 June 2017." Regarding the question of assessment without a diagnosis of CRPS, the Panel found (at CB p. 104 [51] - [52]): "51. [The submission that the right elbow and wrist restrictions should have been assessed for WPI] must be rejected. The agreement between the parties was that the nominated three areas of the right upper extremity could only be assessed if CRPS were present. The appellant's argument was incorrect when it submitted that Chapter 17 authorised an assessment to be made for range of motion based methodology regardless of whether CRPS was found. Range of motion is only available after CRPS has been found. Table 17.1 provides that the diagnostic criteria for CRPS requires there to be found specified symptoms, signs and complaints. If that criteria is established (sic), then an AMS was able to consider range of motion deficits with regard to both Type 1 and Type 2 of CRPS. Chapter 17.5 contains Table 17.1, and provides relevantly that once the diagnostic criteria are established: "Then consider the following in assessing CRPS1: If the criteria in each of the sections 1, 2, 3 and 4 in Table 17.1, above, area satisfied, the diagnosis of CRPS1 may be made. Rate the extremity impairment resulting from loss of motion of each individual joint involved. Rate the extremity impairment resulting from sensory deficits and pain… Combine the extremity impairment for loss of joint motion with the impairment for pain or sensory deficit… Convert the final extremity impairment to WPI using AMA5 Table 16.3, (p 439) for the upper extremity and AMA5 Table 17.3 (p 527) for the lower extremity. Complex Regional Pain Syndrome Type 2, causalgia For Complex Regional Pain Syndrome Type 2 (CRPS2), the mechanism is an injury to a specific nerve. The methodology in AMA5 (pp 496 - 97) is to be followed: If the criteria in each of sections 1, 2, 3 and 4 in Table 17.1, above, are satisfied and there is objective evidence of an injury to a specific nerve, the diagnosis of CRPS2 may be made. Rate the extremity impairment due to loss of motion of each individual joint involved. Rate the extremity impairment resulting from sensory deficits and pain of the injured nerves… Rate the extremity impairment resulting from motor deficits and the loss of power of the injured nerve according to the determination method in AMA5 Chapter 16, Section 16.5b and Table 16-11a." 52. There is accordingly no substance in the argument that the Guides authorised an assessment for range of motion deficits where CRPS had not been established. The appellant sought to avoid that outcome by arguing that the terms of the referral should be construed to read that the requirement for CRPS to be established only related to the claim within the parenthesis for the peripheral nerves. He did not attempt to explain how the claims for the right shoulder, elbow and wrist, which were also within the parenthesis, were exempted from the CRPS condition. 53. Further, whilst there was no bright line that delineates causation from medical evidence, it is for the Commission to determine whether a worker has suffered an injury within the meaning of section 4 [WCA]. The appellant submitted that the injury to the right shoulder was a material factor in the development of the restricted range of motion in the right elbow and wrist. 54. This claim had not hitherto been made, and accordingly the respondent had not been given an opportunity to consider it. As indicated, we find it difficult to see in any event how such a construction of the referral could have been made by the AMS, as the reference to the elbow and the wrist was contained in the same parenthesis as the reference to CRPS, Type 2." AMA5 is a reference to the American Medical Association's Guides to the Evaluation of Permanent Impairment (5th edition) adopted and modified by the SIRA guidelines. Citations within the quoted passage are to these guidelines. The reference to the agreement of the parties is to the agreement as to the amendment of the original referral.

Grounds of Review

1. The Grounds of Review as stated in the amended summons are as follows: "a) The Second Defendant erred in point of law and made a jurisdictional error when it held that an assessment by range of motion was only available if CRPS was found. b) The Second Defendant erred in point of law and made a jurisdictional error when it held that the Guides did not authorise assessment for range of movement where CRPS had not been established. c) The Second Defendant erred in point of law and made a jurisdictional error when it failed to hold that the referral required an assessment of whole person impairment resulting from the accepted injury to the shoulder. d) The Second Defendant erred in law and made a demonstrable error when it held that the referral restricted the AMS from assessing the impairment resulting from the injury and only permitted an assessment of the elbow and wrist if there was a finding of CRPS such as to allow an assessment applying chapter 17 of the Guides. e) The Second Defendant erred in law and made a jurisdictional error when it held that the AMS was restricted by the referral to only assessing impairment of the elbow and wrist if he found CRPS when the claim was for impairment resulting from injury to the right shoulder, elbow and wrist. f) The Second Defendant erred in law and made a jurisdictional error when it held that the Registrar could limit the impairments to be assessed to those impairments that exist when there is a finding of CRPS when the Registrar's only power was to refer a medical dispute for assessment."
2. At the commencement of the hearing, Mr McManamey of counsel who appeared for the plaintiff sought leave to rely on an additional ground of review, being: "g) The Second Defendant erred in law on the face on the record and made a jurisdictional error when it asked the wrong question to identify the dispute that had been referred for assessment."

Grounds (a) and (b)

1. Mr McManamey argued that the scope of the medical assessment is not restricted to the terms of the referral form but is defined by the Application to Resolve a Dispute, the claim letters and medical reports used in support of the respective positions of the parties. He referred to Skates. This would include the degree of impairment in the entirety of the right upper extremity as a result of the original injury to the right shoulder whether or not CRPS was established.
2. Reference was made to Chapter 2 of the SIRA guidelines, which states that AMA5 Chapter 16 applies to the assessment of permanent impairment of the upper extremities, subject to modifications. Proper application of Chapter 2 would require an AMS assessing an upper extremity impairment that results solely from a peripheral nerve injury to assess using range of motion. Counsel accepted that pursuant to paragraph 2.21 of Chapter 16, CRPS should be assessed using Chapter 17, however if CRPS is not present, assessment should be made in accordance with Chapter 16 which also utilises loss of range of motion as a test for measuring impairment.
3. Counsel argued that the decision of the Appeal Panel that "[Mr Mifsud's] argument was incorrect when it submitted that Chapter 17 authorised an assessment to be made for a range of motion-based methodology regardless of whether CRPS was found. Range of motion is only available after CRPS was found" misstated and misunderstood Mr Mifsud's submission in the appeal. The submission was that when Chapter 17 did not apply, the other methods for assessing impairment contained in Chapter 2 of the Guidelines and Chapter 16 of the AMA5 did apply. It was submitted the Appeal Panel erred in its interpretation of the task for the AMS, its interpretation of the SIRA guidelines and its interpretation of the case made to it, amounting to an error in point of law on the face of the record and jurisdictional error.
4. In reply to the employer's submission in relation to the scope of the medical dispute, Mr Mifsud submitted that the dispute properly characterised was the degree of impairment in the right upper extremity as a result of the accepted injury to the right shoulder, assessment of which does not require a finding that there is an injury within the meaning of s 4 WCA to other parts of the right upper extremity.
5. Ms Tronson of counsel, who appeared with Ms Roberts for the employer, argued that all of the grounds of review concern the same central issue, being the question of jurisdictional fact about the bounds of the medical dispute referred to an AMS. The employer's primary submission was that the medical dispute "crystallised in the documents" which "defined the proper scope of the referral", being "the medical dispute the parties have sought to have resolved", was entirely consistent with the terms ultimately applied by the Appeal Panel. She too referred to Skates.
6. The documents that the employer submitted provided the basis for the proper scope of the referral were the Claim Letter dated 10 June 2020, the response from the employer's solicitors, including medical reports of Professor Cumming, a report of Dr Endrey-Walder (referrable to the 2017 agreement; this expert did not diagnose CRPS) and the complying agreement itself. In all the circumstances, Ms Tronson submitted the medical dispute between the parties, as crystallised, comprised: 1. A dispute as to the diagnosis of CRPS; 2. If the diagnosis of CRPS was correct, a dispute as to the consequential degree of permanent impairment; and 3. A dispute as to the permanent impairment in relation to Mr Mifsud's right shoulder injury alone.
7. The employer argued that the only part of the medical dispute relating to Mr Mifsud's right elbow and wrist arose out of the disputed diagnosis of CRPS, and according to the SIRA guidelines, enquiries into range of motion are applicable only following a finding that CRPS, either Type 1 or Type 2, is present. This is consistent with the Appeal Panel's decision, and therefore the decision discloses no error on these grounds.

Ground (c)

1. Mr McManamey submitted that, the law of causation in workers compensation matters being the same as the law of causation at common law. In order for the AMS and Appeal Panel to carry out their assessment, they must consider whether there was a legal chain of causation between the right shoulder injury and the loss of range of movement throughout the rest of the arm. That the right shoulder was not the sole cause of the impairment, and that there was development of CRPS which had since abated, did not mean that the chain of causation had been broken. The correct conclusion was that the loss of range of movement in the entirety of the arm resulted from the accepted injury, perhaps as a residuum of the previous CRPS (see [62] below).
2. Mr McManamey submitted that the Appeal Panel took an incorrect view that the referral had the power to constrain the AMS from carrying out the statutory task of applying the law of causation.
3. Counsel for the employer submitted that the CRPS diagnosis made by A/Prof Boesel had provided the link between the original shoulder injury and impairment in other parts of Mr Mifsud's arm. The CRPS diagnosis was a critical part of the dispute between the parties, and an essential part of the claim in respect of the elbow and wrist, sufficient to break the chain of causation where not present.

Grounds (e) and (f)

1. Mr McManamey submitted that the way that the Appeal Panel approached the issue before it amounted to jurisdictional error. It was submitted that, as indicated in paragraphs 48 to 51 of the Appeal Panel's decision, it took the view that the AMS was constrained by the terms of the referral document, being limitations on the body parts that could be assessed and circumstances in which the body parts could be assessed. This was in error as the Registrar and therefore the delegate do not have power to determine any issue between the parties. Reading the referral as limiting the AMS in the way decided by the Appeal Panel, in only assessing impairment through Chapter 17 of AMA5, amounted to jurisdictional error.
2. Ms Tronson argued that the terms of the referral were plain and reflected the parties' agreement, such that the claim relevantly depended upon the existence of CRPS established in accordance with the SIRA guidelines. Further, the Appeal Panel's decision, whilst placing reliance on the terms of the referral, did determine that it did not accurately reflect the medical dispute as crystallised between the parties, but nevertheless the AMS had in fact assessed the actual medical dispute crystallised between the parties and thus had not erred. This was made clear by the requirement that the referral be amended.
3. It was further submitted that even if the Appeal Panel had erred in the procedure adopted, Mr Mifsud has not shown that the error deprived him of the possibility of a successful outcome: Stead v State Government Insurance Commission (1986) 161 CLR 141; [1986] HCA 54 at 147.

Ground (g)

1. Mr McManamey argued the Appeal Panel's finding that the referral did not reflect the agreement between the parties, its direction at paragraph 61 of its reasons for the parties to agree on a further amended referral and following lack of agreement between the parties, its own determination of the wording of the referral, amounts to jurisdictional error. Counsel argued that the delegate, and then the Appeal Panel, could not direct the AMS on how to assess the dispute, and could not give any direction concerning which parts of the SIRA guidelines and AMA5 are to be applied. As the delegate did not have that jurisdiction, it was immaterial whether those directions were based upon an agreement between the parties.
2. Ms Tronson argued in response that the precise scope of the referral, being what was the medical dispute, was central to what the Appeal Panel was being asked to consider. Counsel relied on the authority of the Court of Appeal in Skates. She submitted that the appropriate enquiry begins with the language of the referral itself and broadens to consider the dispute as reflected in materials, starting with the claim letter. As such, this ground also demonstrates no error.

Relevant provisions

1. Mr Mifsud's application to the AMS for the WPI assessment was made for the purposes of s 39 WCA, which requires assessment as specified by s 65 WCA and Part 7 (Medical assessment) of Chapter 7 of WIM.
2. Where a medical dispute arises an application can be made, now, to PIC for determination of that dispute. A "medical dispute" is defined in the following terms (s 319 WIM): "medical dispute" means a dispute between a claimant and the person on whom a claim is made about any of the following matters or a question about any of the following matters in connection with a claim - the worker's condition (including the worker's prognosis, the aetiology of the condition, and the treatment proposed or provided), the worker's fitness for employment, the degree of permanent impairment of the worker as a result of an injury, whether any proportion of permanent impairment is due to any previous injury or pre-existing condition or abnormality, and the extent of that proportion, the nature and extent of loss of hearing suffered by a worker, whether impairment is permanent, whether the degree of permanent impairment of the injured worker is fully ascertainable.
3. Upon a dispute being referred to PIC, it can then be referred for assessment by medical assessor, pursuant to s 293 as follows: When a dispute referred for determination by the [PIC] concerns a medical dispute within the meaning of Part 7, the President may (subject to the regulations under section 321A (Referral of medical dispute concerning permanent impairment)) refer the medical dispute for medical assessment under Part 7, and defer determination of the dispute by the [PIC] pending the outcome of that medical assessment. (Repealed) The President may not refer for assessment - (Repealed) A medical dispute other than a dispute concerning permanent impairment (including hearing loss) of an injured worker, except when dealing with the dispute under Part 5 (Expedited assessment).
4. Following the issue of a certificate of the medical assessor pursuant to s 325 WIM, a party may apply to the President to appeal on the grounds contained in s 327(3) WIM, being: deterioration of the worker's condition that results in an increase in the degree of permanent impairment, availability of additional relevant information (but only if the additional information was not available to, and could not reasonably have been obtained by, the appellant before the medical assessment appealed against), the assessment was made on the basis of incorrect criteria, the medical assessment certificate contains a demonstrable error.
5. Procedure on appeal is stipulated by s 328 WIM and is by way of review but limited to the grounds of appeal on which the appeal is made (s 328(2)).

Relevant Guidelines

1. As submitted by the parties, the AMS's assessment of WPI is made pursuant to AMA5 and the SIRA guidelines. It is the employer's case that the AMS, and subsequently the Appeal Panel, correctly assessed WPI in accordance with Chapters 2 and 17, the latter of which relevantly provides (I repeat for convenience): "17. Evaluation of permanent impairment arising from chronic pain … 17.5 AMA5 Section 17.2m, 'Causalgia and complex regional pain syndrome (reflex sympathetic dystrophy)' (p 553), should not be used. AMA5 Table 16-16 (p 496) has been replaced by Table 17.1 in the Guidelines. Table 17.1 is used to determine if complex regional pain syndrome (CRPS) is a rateable diagnosis. It is important to exclude diagnoses that may mimic CRPS, such as disuse atrophy, unrecognised general medical problems, somatoform disorders and factitious disorder. Once the diagnosis is established, access impairment as in AMA5. Complex Regional Pain Syndrome Type 1 For Complex Regional Pain Syndrome Type 1 (CRPS1) to be present for the purposes of assessment: the diagnosis is to be confirmed by criteria in Table 17.1 the diagnosis has been present for at least one year (to ensure accuracy of the diagnosis and to permit adequate time to achieve maximum medical improvement) the diagnosis has been verified by more than one examining physician other possible diagnoses have been excluded. CRPS1 is to be assessed as follows: Apply the diagnostic criteria for complex regional pain syndrome type 1 (Table 17.1). Table 17.1 Diagnostic Criteria for Complex Regional Pain Syndrome types 1 and 2 Continuing pain, which is disproportionate to any causal event. Must report at least one symptom in each of the four following categories: Sensory: Reports of hyperaesthesiae and/or allodynia. Vasomotor: Reports of temperature asymmetry and/or skin colour changes and/or skin colour asymmetry. Sudomotor/oedema: Reports of oedema and/or sweating increase or decrease and/or sweating asymmetry. Motor/trophic: Reports of decreased range of joint motion and/or motor dysfunction (tremor, dystonia) and/or trophic changes (hair, nail, skin). Must display at least one sign* at time of evaluation in all of the following four categories: Sensory: Evidence of hyperalgesia (to pin prick) and/or allodynia (to light touch and/or deep somatic pressure and/or joint movement). Vasomotor: Evidence of temperature asymmetry and/or asymmetric skin colour changes. Sudomotor/oedema: Evidence of oedema and/or sweating asymmetry. Motor/trophic: Evidence of decreased active joint range of motion and/or motor dysfunction (tremor, dystonia) and/or trophic changes (hair, nail, skin). There is no other diagnosis that better explains the signs and symptoms. *A sign is included only if it is observed and documented at time of the impairment evaluation. Then consider the following in assessing CRPS1: If the criteria in each of the sections 1, 2, 3 and 4 in Table 17.1, above, are satisfied, the diagnosis of CRPS1 may be made. Rate the extremity impairment resulting from loss of motion of each individual joint involved. Rate the extremity impairment resulting from sensory deficits and pain, according to the grade that best fits the degree or amount of interference with ADL, as described in AMA5 Table 16.10a (p 482). Use clinical judgment to select the appropriate severity grade and the appropriate percentage from within the range shown in each grade. The maximum value is not automatically applied. The value selected represents the extremity impairment. A nerve value multiplier is not used. Combine the extremity impairment for loss of joint motion with the impairment for pain or sensory deficit using the Combined Values Chart (AMA5, p 604) to obtain the final extremity impairment. Convert the final extremity impairment to WPI using AMA5 Table 16.3, (p 439) for the upper extremity and AMA5 Table 17.3 (p 527) for the lower extremity. Complex Regional Pain Syndrome Type 2, causalgia For Complex Regional Pain Syndrome Type 2 (CRPS2), the mechanism is an injury to a specific nerve. The methodology in AMA5 (pp 496-97) is to be followed: If the criteria in each of sections 1, 2, 3 and 4 in Table 17.1, above, are satisfied and there is objective evidence of an injury to a specific nerve, the diagnosis of CRPS2 may be made. Rate the extremity impairment due to loss of motion of each individual joint involved. Rate the extremity impairment resulting from sensory deficits and pain of the injured nerves according to the determination methods described in AMA5 Chapter 16, Section 16.5b and Table 16-10a. Use clinical judgement to select the appropriate severity grade and the appropriate percentage from within each range shown in the grade. Rate the extremity impairment resulting from motor deficits and the loss of power of the injured nerve according to the determination method in AMA5 Chapter 16, Section 16.5b and Table 16-11a. Combine the extremity impairment percentages for loss of range of motion of the joints involved, pain or sensory deficits, and motor deficits, if present, to determine the final extremity impairment, using the Combined Values Chart in AMA5 (p 604). Convert the final extremity impairment to WPI using AMA5 Table 16.3 (p 439) for the upper extremity and AMA5 Table 17.3 (p 527) for the lower extremity."
2. Mr McManamey submitted that an alternative pathway to assessment was available to the AMS through Chapter 2 of the SIRA guidelines incorporating Chapter 16 of AMA5, as modified. The relevant provisions of Chapter 2, as submitted by Counsel for Mr Mifsud, are in the following terms: "2. Upper extremity AMA5 Chapter 16 (p 433) applies to the assessment of permanent impairment of the upper extremities, subject to the modifications set out below. … Specific interpretation of AMA5 - the hand and upper extremity impairment of the upper extremity due to peripheral nerve disorders 2.9 If an upper extremity impairment results solely from a peripheral nerve injury, the assessor should not also evaluate impairment(s) from AMA5 Section 16.4 'Abnormal motion' (pp 450-79) for that upper extremity. AMA5 Section 16.5 should be used for evaluating such impairments. … Complex regional pain syndrome (upper extremity) 2.21 Complex regional pain syndrome types 1 and 2 should be assessed using the method in Chapter 17 of the Guidelines." I repeat that, CRPS aside objectively determined loss of the normal range of movement in the joints of the upper extremities is a relevant criterion for measuring the degree of impairment of general application.

Relevant legal principles

1. Although many cases were referred to in written submissions, the parties seemed to agree generally about the principle arising out of Skates, (33.3T). That matter concerned the judicial review of a decision of an Appeal Panel which set aside the decision of an AMS, and reassessed the appellant's, Mr Skates, WPI. The primary judge made orders setting aside the decision of the Appeal Panel and remitting the matter to the Registrar (being the relevant repository of the statutory power at the time) on a limited basis.
2. On appeal, the Court of Appeal (Basten JA, Leeming JA agreeing with separate reasons, McCallum JA dissenting) granted leave to appeal on limited grounds (to set aside the decision, and direct that further referrals to include the left wrist as a body part to be assessed), and otherwise dismissed the application for leave to appeal. The wording of the referral to the AMS in Skates was in the following terms: "Body part/s referred: Left Upper Extremity (joint ring finger), Scarring (TEMSKI)". It had been conceded by the insurer that this referral should have included the left wrist, however the Appeal Panel did not give effect to that concession, considering itself bound by the terms of the referral. By Adamson J at first instance, and on appeal to the Court of Appeal, it was found that the wrist should have been included in the terms of the referral, however, the assessment by the AMS had contained demonstrable error in as much as the AMS seemed to have dealt with the question of degree of impairment as though it were at large rather than limited by the terms of claim (at [35]).
3. Relevantly for Mr Mifsud's case, the respective judgments of Basten JA and Leeming JA elucidated the process of the appeal from an AMS assessment, and the interpretation of a referral of a medical dispute. Basten JA considered the proper scope of the referral as being defined by the material forming the application for assessment and the medical reports enclosed with the application (at [27] - [30]). Specifically, his Honour looked at the "injury details" provided on the form, the "body parts/systems claimed" listed at part 5.6 of the form, and the injuries referred to in the medical reports enclosed with the application.
4. The judgment of Leeming JA is, with respect, to the same effect as the judgment of Basten JA but differently expressed. I think it instructive to quote from His Honour's judgment (at [46] - [50]): "[46] The dispute between Mr Skates and the insurer was crystallised by the correspondence attached to Mr Skates' application; indeed, it was why the documents setting out both sides' claims were attached. That was the dispute which was referred to the Commission pursuant to s 288. It was a "medical dispute" because the parties had made different claims about the degree of permanent impairment suffered by Mr Skates as a result of the injury. It was therefore apt to be referred for medical assessment. The point of doing so was to resolve the dispute. [47] Sections 321 and 321A concern referrals of a dispute for assessment. The language of the heading of each section commences "Referral of medical dispute" and each provision confirms that it is the medical dispute which is referred for assessment. Section 293 authorises the referral of a medical dispute for medical assessment and the deferral of determination of the dispute. All these provisions proceed on the basis that the outcome of the assessment is the resolution of the medical dispute. So too does the conclusive presumption of correctness accorded by s 326 to assessments which are certified in a medical assessment certificate. [48] The paperwork associated with the administration of the legislation seems to have led to a tendency to give to the document comprising the "referral" to an Approved Medical Specialist a greater status than it warrants. The document is important. However, the fundamental legal concept is a dispute. In the absence of a dispute, the worker and the insurer would not need to go to the Commission. An important category of disputes is medical disputes, and the referral of the medical dispute to an Approved Medical Specialist is but an aspect of the statutory scheme to resolve the dispute. [49] The document signed by the Registrar's delegate and dated 1 September 2017 described itself as a "Referral for Assessment of Permanent Impairment to Approved Medical Specialist". Its first numbered subheading was "Medical Dispute Referred for Assessment" and there it stated, wrongly, "Body part/s referred: Left Upper Extremity (joint ring finger), Scarring (TEMSKI)". That was wrong insofar as it did not include Mr Skates' wrist. The later referral contained the same poor language and contained additional errors. But the infelicity of parts of the covering document cannot stand in the way of the fact that it was the dispute between the parties, crystallised in the documents attached to that covering document, which was referred for assessment in accordance with the statute. The Appeal Panel was correct to state that the Approved Medical Specialist had gone beyond assessment of the medical dispute which had been referred to him. [50] The foregoing substantially corresponds with the first explanation given by Basten JA for confirming the correctness of the result reached by the Appeal Panel and the primary judge, with a heavier emphasis upon the purpose of the statutory regime being to resolve a medical dispute and that a dispute is identified by the disputants' competing claims." (My emphasis.)
5. McCallum JA's dissenting judgment was not different in substance. However, her Honour disagreed, on the facts, that the content of the dispute excluded Mr Skates' "left upper extremity" generally. In her Honour's view, that was clear from Mr Skates application to have the dispute referred for assessment. With respect her Honour made the key point (at [82]), "the medical dispute referred must be the medical dispute the parties have sought to have resolved". Her Honour added (at [83]) that the only dispute the Registrar had power to refer included a dispute as to the impairment of the left upper extremity. It was this latter proposition which put her Honour in dissent.
6. After the hearing before me had concluded the Court of Appeal constituted by the same judges of appeal decided Queanbeyan Racing Club Ltd v Burton [2021] NSWCA 304 ("Burton"). Burton was concerned with a somewhat different issue about the powers of the Appeal Panel to determine an appeal. The question was whether it was entitled to have regard to and incorporate in its determination undisputed findings of the AMS from whom the appeal lay or had to exercise the power of assessment entirely afresh for itself. The Court of Appeal (Basten JA, Leeming and McCallum JJA agreeing) decided that the former proposition was correct.
7. In the course of his judgment, Basten JA albeit in the context of the content of the Appeal Panel's obligation to afford the parties procedural fairness made certain observations which are, with respect, apposite to the present case. His Honour said (at [42] - [43]): "[42] With respect to both issues, the starting point for any understanding of procedural fairness must be the statutory scheme within which it is said to operate. The following statement by the High Court in Wingfoot Australia Partners Pty Ltd v Kocak ((2013) 252 CLR 480; [2013] HCA 43) ("Wingfoot v Kocak") made in relation to the standard required of reasons given by a medical panel, is equally applicable to the functions of an Appeal Panel under the New South Wales legislation: "[47] The function of a Medical Panel is neither arbitral nor adjudicative: it is neither to choose between competing arguments, nor to opine on the correctness of other opinions on that medical question. The function is in every case to form and to give its own opinion on the medical question referred to it by applying its own medical experience and its own medical expertise." [43] A definition of a medical term is inherently something within the medical experience or expertise of the medical members of the Appeal Panel. They do not have to express those terms in language which is within the experience or expertise of the parties. Nor, if they wished to identify a distinction between evoked and spontaneous sensations, did they need to identify the authority which permitted either or both to be taken into account in assessing a particular condition. These were matters to be determined by the Panel in the exercise of their medical expertise. However, if in giving reasons both the distinction and the medical authority were identified, they did not become matters which fell within any obligation of advance disclosure to the parties."
8. From these decisions, I derive the following principles relevant to the resolution of the present dispute. While the High Court's decision in Wingfoot v Kocak has been routinely applied in the context of the New South Wales legislation as descriptive of the statutory function of an appeal panel, or for that matter, AMS, the task of the AMS and Appeal Panel is fundamentally dispute resolution. I interpolate, the medical panel in Wingfoot v Kocak was required to resolve a presumably contested medical question. Even so, in discharging its functions under WIM, an appeal panel is not reduced to a choice between competing arguments or an evaluation of the opinions of other medical experts. Still, it is not purely a neutral expert evaluation. The discharge of the statutory functions of the AMS or Appeal Panel is not at large. Each of the AMS and Appeal Panel are restricted to the resolution of the dispute joined between the parties. The identification of the dispute however is not inflexibly fixed by the terms in which the dispute is referred to the AMS by, formerly, the Registrar or, laterally, the President of the PIC. As Leeming JA put it in Skates "the document comprising the "referral" to an approved medical specialist" should not be afforded "a greater status than it warrants" (at [48]); or as McCallum JA would have it, the only dispute the Registrar has power to refer "must be the medical dispute the parties have sought to have resolved" (at [82]).
9. Additionally, Basten JA pointed out (at [31]): "… once it is accepted that the scope of the referral was properly capable of restriction by reference to body parts/systems, the question as to how the Appeal Panel read the referral may well have been a matter for its professional judgment and not one involving reviewable error." Nonetheless, as I read it, it is central to his Honour's decision that Mr Skates' claim "was in fact wider than the referral", which was conceded by the employer, and the AMS, or Appeal Panel, as the case may be, was bound to resolve the matter which was in substance in dispute even if the content of the dispute formulated by consideration of all the relevant material extended beyond the precise terms of the referral.
10. All of the judges of appeal accepted that identification of the dispute was undertaken by reference to the terms of the injured worker's claim, the employer's response, the medical opinions upon which they respectively relied and the terms of the referral. The medical opinions upon which the parties respectively relied are likely to be of some importance given that what is to be resolved is a medical dispute. At the same time the AMS or Appeal Panel is not restricted, consistently with Wingfoot v Kocak, to choose between the competing medical positions adopted by the parties qualified experts. The AMS or the Appeal Panel is bound to resolve the parties' dispute by the expression of its own expert opinion. As Leeming JA (at [50]) pithily summed up the position: "a dispute is identified by the disputants' competing claims" (original emphasis).

Decision

1. Mr McManamey does not contend that the task of either the AMS or the Appeal Panel was at large. He accepts it was restricted by a proper identification of the content of the actual medical dispute between the disputants. However as was made clear in his written submissions in support of the appeal from the MAC to the Appeal Panel, he argues that, accepting that the Chapter 17 criteria for establishing CRPS were not made good in Mr Mifsud's case, the AMS, at first instance, and relevantly for my purposes, the Appeal Panel on reviewing the MAC were required in the proper exercise of their statutory function to determine the cause of the impairment in Mr Mifsud's right upper extremity indicated by the limitation in the range of movement in his right elbow and wrist. If in the exercise of the Appeal Panel's medical expertise, acknowledging that its third member is a medical layman, the degree of impairment constituted by those matters was a consequence of Mr Mifsud's work injury in terms of having been caused, or materially contributed to, say, by some "intra-operative" occurrence, then that impairment should have been assessed in accordance with the guidelines and combined with the undoubted impairment referable to Mr Mifsud's right shoulder injury to produce the relevant degree of WPI. Part of Mr McManamey's argument is that the Appeal Panel asked itself the wrong question by focusing upon the precise grammatical meaning of the terms of the referral, which with respect, was perhaps not a model of plain English expression, rather than on the substance of the dispute as constituted by the disputant's competing claims. On a proper construction of the SIRA guidelines and AMA5, the restriction of the range of movement in Mr Mifsud's right elbow and wrist was relevant to the assessment of impairment accepting he failed to establish CRPS in accordance with the requirements of Chapter 17 of the SIRA guidelines.
2. Although the argument on each side of the record, as I have tried to demonstrate by reference to my summary of their competing positions, was elaborated both orally and in writing in much greater detail and by reference to far more authorities, this is essentially what the issue came down to.
3. I am prepared to accept that the Appeal Panel seems to have failed to understand and address Mr McManamey's argument about the alternative means of using loss of range of movement in the joints of the arm to assess impairment even when CRPS was not involved. I also accept that the Appeal Panel tethered itself too tightly to the terms in which the referral was expressed rather than taking a broader view of the material which defined the particular medical dispute between the parties which they had presented for resolution. I am of this view notwithstanding its decision that the terms of the referral required amendment to include assessment of shoulder impairment as a result of the frank injury. Indeed, this circumstance rather establishes the point. Contrary to what the Appeal Panel said, the AMS did not take a "pragmatic approach", rather he identified the scope of the dispute by reference to the materials as required by law. He did not limit himself to the terms of the referral.
4. I acknowledge that the Appeal Panel required the amendment of the referral in obedience to the judgment of Adamson J in Skates v Hill Industries Ltd at first instance ([2020] NSWSC 837 at [73]). However, it seems to me that the Court of Appeal, in its judgment in Stakes, handed down after the Appeal Panel's decision, has taken a broader approach. In my judgment, it is erroneous for an AMS or an appeal panel to treat the precise terms in which the referral is expressed as fundamental to jurisdiction or power. If this is so, amendment was strictly unnecessary even if it may have been expedient. With some hesitation having regard to what Basten JA said in Skates (at [31]) about the bounds of the Appeal Panel's medical expertise, I would be prepared to hold that focusing solely upon the terms of the referral may in some cases constitute jurisdictional error or constructive jurisdictional error.
5. I am accordingly satisfied that Mr Mifsud has established error on the part of the Appeal Panel on these two bases. The question then is: are these errors either jurisdictional or errors of law on the face of the record requiring the intervention of this Court?
6. My difficulty in the present case is that I do not regard these "errors", if I'm correct about them, as material: Hossain v Minister for Immigration and Border Protection (2018) 264 CLR 123; [2018] HCA 34. If one considers the material, other than the terms of the referral, which defines the dispute, the sole justification for considering both of Mr Mifsud's elbow and wrist restrictions as part of his overall work-related impairment is the hypothesis propounded by A/Prof Boesel that Mr Mifsud suffered CRPS Type 2 due to an intra-operative occurrence. An occurrence of this type would be a consequence of the frank work injury to his right shoulder which the surgery was undertaken to treat. A/Prof Boesel's opinion was foundational to Mr Mifsud's "claim".
7. The employer's "claim" based upon the opinion of Professor Cumming was that Mr Mifsud may have had a symptom complex which was CRPS-like which had at least a temporal connection with the shoulder surgery Mr Mifsud underwent. However, the clinical signs did not satisfy the Chapter 17 criteria for CRPS Type 1 or Type 2. And there was a competing hypothesis which required further investigation, that Mr Mifsud's wrist and hand symptoms (Professor Cumming thought the elbow normal) was irritative carpal tunnel syndrome which required further investigation but if present, probably, would be amenable to surgery notwithstanding its apparent chronicity.
8. If this was the medical dispute that the AMS was required to resolve, subject to any review by the Appeal Panel, then the only causal pathway supporting Mr Mifsud's case in anatomical, physiological or other medical terms was CRPS which was rejected by the AMS whose decision in this regard was not challenged on appeal to the Appeal Panel.
9. It is important to emphasise that Mr Mifsud now accepts that CRPS does not provide the relevant causal pathway required by the terms of s 66 WCA to found an entitlement to permanent impairment compensation. So far as is material, s 66 WCA provides: a worker who receives an injury that results in a degree of permanent impairment greater than 10% is entitled to receive from the worker's employer compensation for that permanent impairment as provided by this section.
10. It is for Mr Mifsud to demonstrate that his injury "results in" the permanent impairment for which he contends. The phrase "results in" connotes legal causation in the sense of permanent impairment caused by or materially contributed to by the work injury. This will typically require the establishment of medical causation, subject to the principles established in Adelaide Stevedoring Co Ltd v Forst (1940) 64 CLR 538; [1940] HCA 45 and subsequent cases.
11. When pressed about this during oral argument Mr McManamey responded (at 29.5T) consistently with his written submissions: "… one of the things that was available to [the Appeal Panel] was to look at the entirety of the evidence and come up with the conclusion that whilst [Mr Mifsud] did not have CRPS as at that time, he had nonetheless in the past had a condition which had features of CRPS, was causally related to the shoulder and that the loss of range of movement in the elbow and the wrist was a consequence of that." Learned Counsel accepted that there was no evidence that you could have a past condition of CRPS that might be linked to such losses which were relevantly permanent (29.10T). These are medical questions but there is no medical material in Mr Mifsud's "claim" supporting this alternative analysis.
12. The central terms of the referral for medical assessment are set out above (at [11]), as are the relevant terms of the Appeal Panel's decision (at [18]). Considering this material together it is quite clear from the Appeal Panel's decision at [54] that the Appeal Panel decided that the only construction of the referral available in effect was that the assessment of the degree of impairment of Mr Mifsud's right upper extremity was restricted to that caused by CRPS Type 2. The Appeal Panel seemed to have arrived at that conclusion on the basis that all of the body parts mentioned in the parenthesis of the referral were qualified by the concluding words "- as a result of CRPS Type 2 (if present)". With respect, the Appeal Panel's own decision acknowledged that the impairment of Mr Mifsud's right shoulder was referrable to the frank injury suffered. As I have said, I accept it was an error for the Appeal Panel to focus on the referral. On the other hand, the claim that the additional impairment constituted by the loss of range of motion in Mr Mifsud's elbow and wrist was related to the injury otherwise than "as a result of CRPS Type 2", according to the Appeal Panel, "had not hitherto been made". This finding is not impugned before me. Effectively, the Appeal Panel was refusing to permit it to be made for the first time on appeal because the employer had not had the opportunity to consider it. Moreover, the precise terms of the referral had been agreed between the parties as the content of the Affidavit of Ms Loren Rich affirmed on 17 August 2021 and read on the hearing (CB p. 385 ff) made clear. Ms Rich made clear that she understood that A/Prof Boesel's assessment "was only made on the basis of a finding and diagnosis of CRPS Type 2, not as the result of frank injuries to those body parts". On that basis Mr Mifsud's solicitors agreed with the formulation of the referral proposed by Ms Rich in the same terms as I have set out above (at [11]) (CB p. 429). The Appeal Panel laid some emphasis upon the fact that the formulation of the referral was an agreed position between the parties (Appeal Panel decision [44]; CB p. 379). This was open to the Appeal Panel.
13. Moreover, CRPS was the only means by which the whole of Mr Mifsud's asserted WPI by reference to the condition of his right upper extremity could be said to have resulted from his work injury. Had the Appeal Panel looked beyond the terms of the referral they would have identified the dispute by reference to "the disputants competing claims" and decided that the only hypothesis available on the material before them by which the condition of Mr Mifsud's right elbow and wrist could be included in an assessment of permanent impairment resulting from his work injury was by the causal pathway of CRPS which ground, pressed before the AMS, had been abandoned before them. Thus, neither tethering themselves too tightly to the terms of the referral nor misunderstanding Mr McManamey's argument about an available basis for assessment under Chapter 2, SIRA guidelines and Chapter 16 AMA5 was a material error.
14. In my judgment Mr McManamey properly conceded before me there was no evidence before the Appeal Panel to establish a post-CRPS restriction in movement in Mr Mifsud's right wrist and elbow allowing the Appeal Panel to make good the necessary causal link. As I have said, Professor Cumming's opinion was not to the point as he did not accept the restriction of movement in Mr Mifsud's right elbow.
15. I should also emphasise that no application was made for the medical members of the Appeal Panel, or one of them, to re-examine Mr Mifsud to make an independent assessment of Mr Mifsud's condition. The failure of the Appeal Panel to re-examine Mr Mifsud is not complained of as a ground of judicial review. In circumstances where no re-examination took place, it is difficult to see how the Appeal Panel could have arrived at an alternative hypothesis, not articulated in the medical material proffered by either party, which they were prepared to accept as the correct conclusion supporting the degree of WPI for which Mr Mifsud contended.

Orders

1. For these reasons I am not satisfied that jurisdictional error or error on the face of the record has been established on any ground contended for by Mr Mifsud and I order: 1. Proceedings for judicial review is dismissed. 2. The plaintiff is to pay the First Defendant's costs of the proceedings.

DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated. Decision last updated: 29 July 2022