Supreme Court New South Wales Medium Neutral Citation: Cowcher v Allianz Australia Insurance Limited [2019] NSWSC 572 Hearing dates: 9 May 2019 Date of orders: 23 May 2019 Decision date: 23 May 2019 Jurisdiction: Common Law Before: Bellew J Decision: (1) The proceedings are dismissed. (2) I reserve the question of costs. (3) The plaintiff is to provide written submissions, not exceeding two pages in length, on the question of costs by 27 May 2019. (4) The defendant is to file any submissions in reply, not exceeding two pages in length, by 29 May 2019. Catchwords: ADMINISTRATIVE LAW – Judicial Review – Review of decision of Proper Officer that there was no reasonable cause to suspect that a medical assessment was incorrect in a material respect – Where plaintiff had undergone hip replacement pre-accident – Where hip replacement was revised as a consequence of accident – Where medical assessor concluded that the plaintiff had suffered no whole person impairment as a consequence – Where Proper Officer had refused an application for a referral of the matter to a medical panel for review – Whether the decision of the Proper Officer was legally unreasonable – Operation of impairment guidelines and medical assessment guidelines – No error established – Proceedings dismissed Legislation Cited: Motor Accidents Compensation Act 1999 (NSW) Cases Cited: Dominice v Allianz Australia Insurance Limited [2017] NSWCA 171; (2017) 81 MVR 249 Elliott v Insurance Australia Limited trading as NRMA Insurance [2014] NSWSC 1848 Meeuwissen v Boden (2010) 78 NSWLR 143; [2010] NSWCA 253; (2010) 56 MVR 453 Minister for Immigration and Citizenship v Li (2013) HCA 18; (2013) 249 CLR 332 Category: Principal judgment Parties: Sharon Cowcher – Plaintiff Allianz Australia Insurance Limited – First defendant Dr Mark Burns as the Approved Medical Assessor, appointed under s 59 of the Motor Accidents Compensation Act 1999 (NSW) – Second defendant The Proper Officer of the Motor Accidents Medical Assessment Service as appointed by SRIA – Third defendant Representation: Counsel: C Hart – Plaintiff J Catsanos – First defendant Solicitors: Bale Boshev – Plaintiff Moray and Agnew – First Defendant File Number(s): 2018/390310 Publication restriction: Nil Judgment INTRODUCTION 1. By an amended summons filed on 9 May 2019 Sharon Cowcher ("the plaintiff") seeks (inter alia) an order which has been pleaded in the following terms: A declaration that the decision of the third defendant dated 4 November 2018 failing to allowing (sic) the plaintiff's application to appeal the Medical Assessment Certificate of Dr Mark Burns, dated 20 July 2018 ("the MAC") ("the second defendant") including reasons ("the gateway decision"), is affected by error of law on the face of the record and by jurisdictional error and ultra vires, together with an order in the nature of certiorari, quashing that decision. 1. It should be noted that an original prayer for relief which was pleaded in the originating Summons in respect of a decision made by the second defendant was abandoned at the commencement of the hearing. 2. A joint court book containing all evidence and pleadings was admitted by consent and marked Exh A. 3. The first defendant, who is the only active defendant in the proceedings, has opposed the relief sought. FACTUAL BACKGROUND 1. The plaintiff is 83 years of age. She was involved in a fall in 2009 when she sustained a cerebella haemorrhage and a right sided hemiplegia. She was admitted to an aged care facility in 2013. She is either bed-bound or wheelchair-bound, and is not able to stand or walk independently. 2. Prior to her fall in 2009 the plaintiff had also suffered from generalised osteoarthritis involving multiple joints, including both hips and both knees. She eventually had total hip replacements and total knee replacements. The left total hip replacement required revision, and post-operatively a complication ensued, whereby the left hip dislocated. This led to a significant shortening in the plaintiff's left leg. 3. On 26 May 2016, the plaintiff attended a dental appointment and a disabled taxi was arranged to bring her back to her aged care facility. She was travelling in the taxi in her own chair during the return trip when the taxi was forced to stop quickly. As a result, she slipped forward under the seat belt which was holding her in the chair, and fell heavily onto her right knee. She was taken to hospital where it was noted that she had significant pain in the region of the right femur. No other injuries were noted. Examination of her right leg revealed tenderness over the mid-shaft of the right femur. 4. The plaintiff came under the care of Dr Dewar, an orthopaedic surgeon, who carried out a revision of her right total hip replacement on 27 May 2016. The plaintiff was subsequently transferred back to her aged care facility. She was re-admitted to hospital on 9 June 2016 complaining of increasing pain in the region of her right thigh, and swelling around her right knee. X-rays of her right hip on 9 June 2016 revealed that the right total hip replacement remained in good position. The peri-prosthetic fracture involving the mid femoral shaft was now shown to have moderate medial and posterior displacement with slight shortening. 5. Further surgery was carried out on 10 June 2016 by way of open reduction and internal fixation of the peri-prosthetic fracture of the mid-femoral shaft fracture. The plaintiff was subsequently discharged back to the aged care facility on 16 June 2016. She was followed up in the Outpatient Orthopaedic Clinic at John Hunter Hospital until 14 November 2016. Her post-operative progress was good and no further follow up was done after that date. THE PLAINTIFF'S CLAIM FOR DAMAGES 1. The plaintiff made a claim for damages pursuant to the provisions of the Motor Accidents Compensation Act 1999 ("the Act") in respect of her injuries arising out of the incident on 26 May 2016. She was referred to a medical assessor, Assessor Mark Burns, for a determination of whether her degree of permanent impairment as a consequence of any injury caused by the accident was greater than 10%. THE MEDICAL ASSESSMENT 1. Assessor Burns carried out an assessment of the plaintiff on 19 July 2018. On 20 July 2018 he issued a certificate stating that the plaintiff's whole person impairment in respect of injury caused by the accident was not greater than 10%. 2. Under the heading "Degree of Permanent Impairment" [1] Assessor Burns said the following: From the documentation I reviewed I note that her right total hip replacement was not actually injured in the motor vehicle accident. Her only injury was a peri-prosthetic fracture of the right femoral shaft. This did though lead to a revision of her right total hip replacement presumably to use a longer femoral prosthesis to provide some splinting at the level of the peri-prosthetic fracture. Thus, the revision of her right total hip replacement would be considered as being causally related to the fracture. The right femoral fracture can be assessed utilising either Table 65 of the 4th Edition of the AMA Guides, which is a rating for hip replacement or Table 64 where femoral shaft fractures can also be assessed. It is difficult to assess her right total hip replacement because of her significant immobility both before and after the current motor vehicle accident. From my rather difficult discussion with her today concerning her pain and discomfort both now and before the accident it would appear that she does have some degree of hip pain but this was also present before the motor vehicle accident. From Point (a) of Table 65 I believe that her pain-would currently be rated as moderate, occasional, which would give 30 points. With respect to Point (b) due to function I note that she is unable to walk at all so therefore would obtain zero points from this area. Additionally, I note from Point (c) dealing with activities her immobility she would obtain zero for stair climbing, zero for putting on her socks and shoes, zero as she cannot use public transport but 2 points as she can sit in a high chair providing she is placed there using the lifter Under Point (d) dealing with deformity I note that she does have a significant decrease in range of movement but would obtain 1 point for less than 102 fixed adduction, 1 point for less than 10s fixed external rotation and 1 point for a flexion contracture for less than 159. She would therefore obtain a further 3 points. With respect to Point (e) her range of movement if only active range of movement were used she would obtain 1 point only. The difficulty with this area is that most of her decrease in range of movement and stiffness is associated with her long standing right hemiplegia. It is not associated with the right total hip replacement. In all she would have a total of 36 points, which would give her a poor rating for her total hip replacement or 30% whole person impairment. I note though that this is not really true assessment of her right total hip replacement as most of her reduction in points is due to her lack of mobility and right sided hemiplegia. I therefore believe that it would be inappropriate to attempt using Table 65 in order to assess her right total hip replacement. I would also point out that when assessing her level of impairment in the right hip prior to the current motor vehicle accident that her points would be almost exactly the same. Again, her pain levels would be classified as moderate and occasional as she was taking Targin for pain in multiple joints (including her hips) prior to the current motor vehicle accident. Her function as well as her activities and deformity would also be exactly the same as would the range of movement. This was because her right hemiplegia has pre-existed the current motor vehicle accident and been present since 2009. I note that the other method of assessment would be using mid shaft fractures of the femur from Table 64. As her mid shaft fracture has now been internally fixed in good position she would obtain 0% whole person impairment from his area. In conclusion I believe that her revision of her right total hip replacement has left her with the same degree of permanent impairment as existed in her right hip prior to the current motor vehicle accident. I do not believe that there has been any increase in the permanent impairment in her right hip associated with the revised total hip replacement. I do believe though that she has acquired 2 further scars with the current revision total hip replacement and subsequent internal fixation. Whilst I have not been able to fully assess these scars 1 note that Dr Isaacs has assessed then at 2% whole person impairment. I am happy to accept his assessment findings. With respect to the medical report of Dr Isaacs dated 06.11.17 I note that under permanent impairment he has assessed the right total hip replacement currently as giving 24 points. He has assessed 20 points for pain, zero points for function, zero points for activities, 3 points for deformity and 1 point for range of motion. He has correctly therefore assessed the hip replacement using these criteria as being a poor replacement giving a 30% whole person impairment. Whilst I believe that this superficially would appear to be correct it should be noted that most of the points have been lost due to the right hemiplegia and total loss of mobility, which had occurred to this lady well before the current motor vehicle accident and the total hip replacement revision. I then note that he has also stated that there was little evidence if any of the total hip replacement before the current motor vehicle accident. Whilst I would partly agree with this, there was significant information though about her total lack of mobility and also her total lack of activities There was also evidence of her pain levels before the accident and the fact that she was already taking Targin I therefore believe that there is significant evidence to show that the assessment of her previous total hip replacement would also have been in the poor category or given 30% whole person impairment Again though, I note that this is not because of the total hip replacement itself but mostly because of her lack of mobility and also her right hemiplegia. I note that Dr Isaacs believes that the only symptom, which is related to the motor vehicle accident on the 26 05 16, was in fact her increase in pain in the right hip. Whilst I would agree with this statement it appears that the pain in her right hip has now settled back to the levels at prior to the fracture of the right femur I note that Dr Isaacs had noted that she was taking Targin after the accident but from the documentation I also note that she was taking Targin before the motor vehicle accident. I also note that rather than assessing the hip as it was before the accident he decided to make a 3 tenths deduction, a methodology which is not allowed under the permanent impairment guidelines for motor accidents. In conclusion taking into account taking into account my clinical judgment and all of the documentary evidence, I believe that Mrs Crowther's permanent impairment in her right hip has remained unchanged since before the current motor vehicle accident. I believe this is adequately supported by her total loss of mobility prior to the current motor vehicle accident and also the fact that her son reported that her mobility and her current medical situation remained unchanged over the last 5 years. THE APPLICATION TO THE PROPER OFFICER FOR REVIEW 1. On 8 August 2018 the plaintiff made an application to the Proper Officer for review of Assessor Burns' determination. That application was made pursuant to s 63 of the Act which is in the following terms: 63 REVIEW OF MEDICAL ASSESSMENT BY REVIEW PANEL (1) A party to a medical dispute may apply to the proper officer of the Authority to refer a medical assessment under this Part by a single medical assessor to a review panel of medical assessors for review. (2) An application for the referral of a medical assessment to a review panel may only be made on the grounds that the assessment was incorrect in a material respect. (2A) If a medical assessment under this Part (a "combined certificate assessment") is based on the assessments of 2 or more single medical assessors (resulting in a combined certificate as to the total degree of permanent impairment), the combined certificate assessment cannot be the subject of review under this section except by way of the review of any of the assessments of the single medical assessors on which the combined certificate assessment is based. (3) The proper officer of the Authority is to arrange for any such application to be referred to a panel of at least 3 medical assessors, but only if the proper officer is satisfied that there is reasonable cause to suspect that the medical assessment was incorrect in a material respect having regard to the particulars set out in the application. (3A) The review of a medical assessment is not limited to a review only of that aspect of the assessment that is alleged to be incorrect and is to be by way of a new assessment of all the matters with which the medical assessment is concerned. (4) The review panel may confirm the certificate of assessment of the single medical assessor, or revoke that certificate and issue a new certificate as to the matters concerned. (5) If on the review of a medical assessment of a single medical assessor on which a combined certificate assessment is based a new certificate is issued by the review panel, the review panel is also to issue a new combined certificate to take account of the results of the review. (6) Section 61 applies to any new certificate or new combined certificate issued under this section. (7) The Motor Accidents Medical Guidelines may limit the time within which an application under this section may be made. THE PROPER OFFICER'S DETERMINATION 1. The Proper Officer commenced [2] by setting out the background to the dispute before identifying the issues as follows: ISSUES IN DISPUTE 5. The applicant submits that the medical assessment is incorrect in the following respects: • Assessment of right hip impairment • Assessment of impairment relating to femoral shaft fracture 1. In respect of the first of those issues, having set out the submissions of the plaintiff, [3] the Proper Officer [4] cited Clauses 1.31 and 1.32 of the Guidelines, which set out the methodology to be undertaken when making apportionments between pre-existing impairments and those resulting from (in this case) a motor vehicle accident. 2. The Proper Officer then went on to say [5] 10. Assessing impairment as a result of a hip replacement requires the use of both Table 64 and Table 65. Table 64 lists the impairment values relating to the three possible outcomes: "Good result, 85-100 points* Fair result, 50-84 points* Poor result, less than 50 points*" 11. At the bottom of Table 64 it is recorded "* See Table 65 (pg. 87) for point rating system". 12. Table 65 is titled "Rating Hip Replacement Results". This takes into account ratings in categories of "Pain", "Function", "Activities" and "Deformity". The Assessor has calculated the appropriate score under table 65 for the current impairment and found that when applied to Table 64 this gives rise to a "poor result" which rates at 30% WPI. He notes however that assessing the hip replacement is made difficult by the effects of the claimant's hemiplegia. 13. He then proceeds to calculate the pre-existing impairment which he also finds equates to 30% WPI. He has then, as required to by clause 1.32, deducted the level of pre-existing impairment from the current impairment. This is a correct application of the Guidelines. 14. I note the analogy provided by the claimant in which an injured person with no pre-existing condition undergoes a hip replacement and is then able to function the same as they had before the injury, but still would be rated as 15% WPI under Table 64. While this may seem like a discrepancy in the guidelines, it actually relates to the difference between "impairment" and "disability". 15. Clauses 1.8-1.12 of the Guidelines provide: 1.8 It is critically important to clearly define the term impairment and distinguish it from the disability that may result. 1.9 Impairment is defined as an alteration to a person's health status. It is a deviation from normality in a body part or organ system and its functioning. Hence, impairment is a medical issue and is assessed by medical means. 1.10 This definition is consistent with that of the World Health Organisation's (WHO) International Classification of Impairments, Disabilities & Handicaps, Geneva 1980, which has defined impairment as 'any loss or abnormality of psychological, physiological or anatomical structure or function'. 1.11 Disability, on the other hand, is a consequence of an impairment. The WHO definition is 'any restriction or lack of ability to perform an activity in the manner or within the range considered normal for a human being'. 1.12 Confusion between the two terms can arise because in some instances the clearest way to measure an impairment is by considering the effect on a person's activities of daily living (that is, on the consequent disability). The AMA4 Guides, in several places, refer to restrictions in the activities of daily living of a person. Hence the disability is being used as an indicator of severity of impairment, (emphasis added) 16. In the analogy suggested by the applicant, while the injured person may not be experiencing any disability after the hip replacement, their hip joint has been replaced with a prosthetic - i.e. there is now a "loss or abnormality of... anatomical structure". 17. As outlined above, the Assessor has calculated impairment in accordance with the AMA IV Guides and Permanent Impairment Guidelines, t am not satisfied there is reasonable cause to suspect the assessment is incorrect in a material respect in this regard. 1. As to the second issue raised by the plaintiff, the Proper Officer commenced by noting the plaintiff's submissions before going on to say: [6] 22. As noted by the respondent, the report of Susan Litchfield dated 3 January 2018 records that post-surgery the fracture was "satisfactorily aligned". This is consistent with the history outlined by the Assessor that the claimant underwent internal fixation surgery and the fracture has been "fixed in good position". The applicant has not provided any evidence which indicates that there was malalignment after the surgery. 1. The Proper Officer concluded: [7] 23. Accordingly, as to this review application, I am not satisfied that there is reasonable cause to suspect that the medical assessment is incorrect in a material respect. 24. The review application is dismissed. THE MOTOR ACCIDENT PERMANENT IMPAIRMENT GUIDELINES 1. The Motor Accident Permanent Impairment Guidelines ("the Guidelines") are issued pursuant to s 133(2)(a) of the Act. Clause 1.2 of the Guidelines is in the following terms: These Guidelines are based on the American Medical Association's Guides to the Evaluation of Permanent Impairment, Fourth Edition (3rd printing 1995). (AMA 4 Guides) However, there are some very significant departures from that document in these guidelines. A medical assessor undertaking impairment assessments for the purposes of the Act must read these Guidelines in conjunction with the AMA 4 Guides. These Guidelines are definitive with regard to the matters they address. Where they are silent on an issue, the AMA 4 Guides should be followed. In particular, chapter 1 and 2 of the AMA 4 Guides should be read carefully in conjunction with clauses 1.1 to 1.46 of these Guidelines. Some of the examples in the AMA 4 Guides are not valid for the assessment of impairment under the Act. It may be helpful for medical assessors to mark their working copy of the AMA 4 Guides with the changes required by these Guidelines (my emphasis). 1. Clause 1.31 of the Guidelines is in the following terms: Pre-existing impairment 1.31 The evaluation of the permanent impairment may be complicated by the presence of an impairment in the same region that existed before the relevant motor accident. If there is objective evidence of a pre-existing symptomatic permanent impairment in the same region at the time of the accident, then its value must be calculated and subtracted from the current WPI value. If there is no objective evidence of the pre-existing symptomatic permanent impairment, then its possible presence should be ignored (my emphasis). THE AMA 4 GUIDES 1. Table 64 of the AMA 4 Guides includes the following: Impairment's Estimates for Certain Lower Extremity Impairments Region and condition Whole-person (lower extremity) Impairment (%) Hip Total hip replacement; includes endoprosthesis, unipolar or bipolar Good result, 85-100 points 15(37) Fear result, 50-84 points 20(50) Poor result less than 50 points 30(75) 1. Table 65 of the AMA 4 Guides is in the following terms: Rating Hip Replacement Results No of points a. Pain 44 None 40 Slight 30 Moderate, occasional 20 Moderate 10 Marked b. Function Limp None 11 Slight 8 Moderate 5 Severe 0 Supportive device 11 None 7 Cane for long walks 5 Cane 3 One crutch 2 Two canes 0 Two crutches 11 Distance walked 8 Unlimited 5 Six blocks 2 Three blocks 0 Indoors In bed or chair c. Activities Stairs climbing Normal 4 Using railing 2 Cannot climb readily 1 Unable to climb 0 Putting on shoes and socks 4 With ease 2 With difficulty 0 Unable to do 4 Sitting 2 Any chair, one hour 0 High chair 1 Unable to sit comfortably 0 Public transportation Able to use Unable to use d. Deformity Fixed adduction <10° >10° 1 Fixed internal rotation 0 <10° 1 >10° 0 Fixed external rotation 1 <10° 0 >10° 1 Flexion contracture 0 <15° 1 >15° 0 Leg length discrepancy <1.5cm >1.5cm e. Range of Motion Flexion >90° <90° 1 Abduction 0 >15° 1 <15° 0 Adduction 1 >15° 0 <15° 1 External rotation 0 >30° 1 <30° 0 Internal rotation >15° <15° SUBMISSIONS OF THE PARTIES Submissions of the plaintiff 1. There was a degree of confusion in ascertaining the precise bases upon which the plaintiff sought judicial review of the Proper Officer's decision. I have already noted [8] the terms in which the relief sought was pleaded in the Summons. When asked to articulate the precise error(s) which were relied upon, counsel for the plaintiff initially said: [9] The first error, your Honour, is that he failed to exercise his statutory power in a way that was reasonable in so far as he determined, without proving (sic) any reasons whatsoever, that the Medical Assessment Decision did not bear, on its face, legal unreasonableness. 1. A second error was then articulated in the following terms: [10] That the Proper Officer erroneously, in a manner that was legally unreasonable, failed to find that the assessment was incorrect in a material respect. 1. It will be apparent that the terms in which these asserted errors were activated were somewhat repetitive. However, counsel confirmed [11] that his submission was that the Proper Officer had reached a decision which was legally unreasonable. Although counsel also made reference to the decision being ultra vires, that assertion was not pressed. It will also be noted that counsel for the plaintiff made an oblique reference to the Proper Officer having failed to give proper reasons. When this was drawn to counsel's attention, he confirmed [12] that he did not make any submission that the Proper Officer's reasons were inadequate. 2. In developing his submissions, counsel for the plaintiff took me firstly to the determination of Assessor Burns. He submitted that Assessor Burns had erroneously concluded that despite the fact that the plaintiff's need for the removal of a hip replacement had arisen as a consequence of the accident, the plaintiff had the same level of whole person impairment as she had prior to the injury. It was submitted that the reasoning of Assessor Burns fell into 'demonstrable error' on account of his failure to assess the category of whole person impairment as prescribed by Table 64 of the AMA 4 Guides. It was submitted that the Proper Officer had, in effect, replicated the error of Assessor Burns and reached a conclusion which was legally unreasonable. 3. Counsel submitted that as a matter of 'simple logic', the application of Table 64 of the AMA 4 Guides 'must score the plaintiff…at least 15% whole person impairment'. The essence of the submission advanced on behalf of the plaintiff was that Table 64 operated in a way which mandated a conclusion that because the plaintiff's previous hip replacement was required to be removed and replaced with another as a consequence of the accident, the plaintiff had suffered a whole person impairment of 15%. 4. Counsel submitted that in these circumstances, in reaching the decision that he was not satisfied that there was a reasonable cause to suspect that Assessor Burns' assessment was incorrect in a material respect, the Proper Officer had reached a conclusion which was legally unreasonable. SUBMISSIONS OF THE FIRST DEFENDANT 1. Counsel for the first defendant submitted that the fundamental premise of the plaintiff's argument was that because the plaintiff had undergone a right hip replacement after the subject accident, there should be a mandatory assessment of 15% whole person impairment based on the AMA 4 Guides, and that it was unreasonable to come to any contrary conclusion. It was submitted that this submission was misconceived, and that the Proper Officer had properly understood, referred to, and taken into account, both the Guidelines and the AMA 4 Guides. 2. Counsel for the first defendant submitted that in order to make out a complaint that the decision of the Proper Officer was legally unreasonable, it was necessary for the plaintiff to establish that the decision was one at which no reasonable person or authority could properly have arrived. It was submitted that it could not be said that the Proper Officer's decision was unreasonable in any sense because it an appropriate (or at least an available) outcome based on the material which was available. CONSIDERATION 1. In Meeuwissen v Boden [13] Basten JA made a number of observations in relation to the operation of s 63 of the Act. Those observations may be summarised as follows: 1. what must be incorrect in a material respect is the medical assessment, not the certificate which results from the assessment; [14] 2. the phrase 'in a material respect' is less precise that the phrase 'capable of having a material effect on the outcome of the previous assessment', the latter being the language of s 62(1A); [15] 3. the power conferred on the Proper Officer is not a discretionary one, such that once satisfied as to the relevant matter, the Proper Officer is to arrange for the application to be referred to a medical panel; [16] 4. the matter of which the Proper Officer must be satisfied is not that the medical assessment was incorrect in a material respect, but only that there is reasonable cause to suspect that it was. Such language is inconsistent with the Proper Officer being expected, let alone required, to carry out an assessment or calculation, as opposed to identifying possible error; [17] 5. where there is doubt as to the extent of the power of an administrative officer, the nature of the power itself must be taken into account. The power under s 63 is that of a gatekeeper, not a decision-maker. Where there is reasonable cause to suspect that a significant error has been made, fairness suggests that the review should be allowed to proceed. In other words, the injured party is entitled to a decision reached in accordance with a proper understanding of the statutory scheme and the facts. Where an important fact has been ignored, the assessment has not been properly undertaken and the statutory right has been subverted. Where a construction is available which would allow a full and proper assessment to occur, in place of a flawed assessment, that construction should be preferred. [18] 1. In the course of argument I was taken to the decision of Campbell J in Elliott v Insurance Australia trading as NRMA Insurance [19] in which his Honour concluded that for the purposes of determining an application under s 63 of the Act, it was likely that a state of satisfaction that there is reasonable cause to suspect that the assessment was incorrect "need not rise above anything other than a state of unease on the part of the proper officer about the correctness of the assessment reading the assessor's reasons and considering the applicant's criticisms of them". [20] Campbell J's determination in that case is limited to its own facts. Moreover, in Dominice v Allianz Australia Insurance Limited [21] Basten JA cautioned against the abandonment of the relevant statutory wording in favour of a paraphrase [22] . 2. Finally, in Minister for Immigration and Citizenship v Li [23] Hayne, Kiefel and Bell JJ observed [24] that legal unreasonableness encompasses error in reasoning, ascribing disproportionate weight to a particular factor or factors, or applying reason which is illogical or irrational. In my view, the decision of the Proper Officer does not fall into any of those categories. 3. Properly understood, the plaintiff's complaint is that it is illogical and unreasonable to conclude that a person who is injured in a motor vehicle accident, and who has undergone a total hip replacement as a result, suffers no permanent impairment as a consequence. Such an approach overlooks, and misunderstands, both the Guidelines and the AMA 4 Guides. 4. In terms of the Guidelines, cl 1.2 provides that they are "definitive with regard to the matters they address". One of the matters that they address (in cl 1.31) is the methodology of evaluating pre-existing impairment. That clause directs that the value of any pre-existing symptomatic impairment must be calculated, and then subtracted from the current WPI value. 5. That was precisely what Assessor Burns did. It was a matter with respect to which the Proper Officer correctly found no error. The Proper Officer's observations, particularly at paragraphs [10] to [19] of his decision, are thorough, disclose no error in approach, and disclose no basis upon which to reach a conclusion that his decision is in any way unreasonable. The conclusion that was reached by the Proper Officer was clearly available to him on the evidence. 6. The approach adopted by the plaintiff also misunderstands the operation of the Guides. The Guides are just that – a guide. Contrary to the general tenor of the submissions advanced on behalf of the plaintiff, they do not operate in a mandatory way, so as to effectively dictate the level of permanent impairment which must be found in a given case. ORDERS 1. For the forgoing reasons I make the following orders: 1. The proceedings are dismissed. 2. I reserve the question of costs. 3. The plaintiff is to provide written submissions, not exceeding two pages in length, on the question of costs by 26 May 2019. 4. The defendant is to file any submissions in reply, not exceeding two pages in length, by 28 May 2019. ********* Endnotes 1. Commencing at CB 72. 2. Commencing at CB 103. 3. Commencing at CB104. 4. At CB 104-105. 5. Commencing at CB 105. 6. Commencing at CB106. 7. CB 107. 8. At [1] above. 9. T5.4-T5.7. 10. T5.17-T5.19. 11. At T5.28. 12. T11.6. 13. (2010) 78 NSWLR 143; [2010] NSWCA 253; (2010) 56 MVR 453 commencing at [19]. 14. At [19]. 15. At [20]. 16. At [21]. 17. At [22]. 18. At [23]. 19. [2014] NSWSC 1848. 20. At [59]. 21. [2017] NSWCA 171; (2017) 81 MVR 249 22. At [12]. 23. (2013) HCA 18; (2013) 249 CLR 332. 24. At [72]. 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: 27 May 2019