CERTIFICATE OF DETERMINATION OF MEMBER  	

Citation:	
Mann v Dahlsens Building Centres Pty Ltd [2022] NSWPIC 599	
		
APPLICANT:	Ross William Mann	
		
RESPONDENT:	Dahlsens Building Centres Pty Ltd	
		
Member:	Rachel Homan	
		
DATE OF DECISION:	27 October 2022	
		
CATCHWORDS:	WORKERS COMPENSATION - Claim for compensation pursuant to section 60 of the Workers Compensation Act 1987 for right hip surgery; accepted injuries to left hip; whether consequential right hip condition; inconsistency in treating surgeon’s reports regarding onset of right hip symptoms; Held – treating medical evidence revealed ongoing left hip symptoms of pain and restriction as well as limping and antalgic gait; treating evidence consistent in indicating a gradual onset of right hip symptoms in the context of ongoing issues with the left hip; inconsistently recorded history of traumatic injury in one of the treating surgeon’s reports likely to be an error and did not outweigh the otherwise consistent evidence regarding onset of symptoms; applicant’s medical evidence preferred; award in favour of the applicant.	
determinations MADE:	1.	The applicant sustained a consequential right hip condition as a result of the injuries to his left hip on 19 November 2004 and 28 June 2010.
2.	The right hip arthroscopy proposed by Dr Parminder Singh is reasonably necessary as a result of the left hip injuries.	
ORDERS made:	3.	The respondent to pay the costs of and incidental to the right hip arthroscopy proposed by Dr Singh in accordance with s 60 of the Workers Compensation Act 1987.	

STATEMENT OF REASONS
BACKGROUND
1.	Mr Ross Mann (the applicant) was employed by Dahlsens Building Centres Pty Ltd (the respondent) as a truss maker between 2003 and 2012.
2.	The applicant sustained an injury to his left hip on 19 November 2004 when he fell through a roof and landed heavily on his left hip.
3.	The applicant sustained a further injury to the left hip on 28 June 2010 when he fell on a thin film of ice whilst carrying timber.
4.	Liability for both injuries to the applicant’s left hip was accepted by the respondent’s insurer.
5.	The applicant claims that as a result of the injuries to his left hip, he has sustained a consequential condition at his right hip.
6.	On 10 September 2019, orthopaedic surgeon, Dr Parminder Singh, sought approval from the insurer for the applicant to undergo a right hip arthroscopy.
7.	Liability for the proposed treatment was disputed in a notice issued pursuant to s 78 of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act) on 13 November 2019. That decision was maintained following internal review in a further notice issued on 4 May 2020.
8.	The present proceedings were commenced by an Application to Resolve a Dispute lodged in the Personal Injury Commission (the Commission) on 2 August 2022. The applicant seeks compensation pursuant to s 60 of the Workers Compensation Act 1987 (the 1987 Act) for the costs of and incidental to the surgery proposed by Dr Singh.
PROCEDURE BEFORE THE COMMISSION
9.	The parties appeared for conciliation conference and arbitration hearing via Microsoft Teams on 24 October 2022. The applicant was represented by Mr James McEnaney, instructed by Ms Sharla Sutcliffe. The respondent was represented by Mr Dewashish Adhikary, instructed by Ms Anna Markley. A representative from the insurer, Mr Eckert, was also present.
10.	During the conciliation conference, the respondent indicated that a dispute as to whether the surgery proposed was reasonably necessary medical treatment for the applicant’s right hip condition was not pressed. The parties were, however, unable to reach agreement with respect to the claim and a dispute as to the causal relationship between the proposed treatment and the accepted left hip injuries was maintained.
11.	I am satisfied that the parties to the dispute understand the nature of the application and the legal implications of any assertion made in the information supplied. I have used my best endeavours in attempting to bring the parties to the dispute to a settlement acceptable to all of them. I am satisfied that the parties have had sufficient opportunity to explore settlement and that they have been unable to reach an agreed resolution of the dispute. 
ISSUES FOR DETERMINATION
12.	The parties agree that the following issue remains in dispute:
(a)	whether the right hip arthroscopy recommended by Dr Parminder Singh is reasonably necessary as a result of the injuries to the left hip on 19 November 2004 and 28 June 2010. 
EVIDENCE
Documentary evidence
13.	The following documents were in evidence before the Commission and considered in making this determination: 
(a)	Application to Resolve a Dispute and attached documents, and
(b)	Reply and attached documents.
14.	Neither party applied to adduce oral evidence or cross examine any witness. 
Applicant’s evidence
15.	The applicant’s evidence is set out in a written statement made by him on 23 October 2020.
16.	The applicant described the injuries to his left hip and stated that as a result of those injuries he had to bear weight on his right side. The applicant started to develop pain and tightness in the right groin and right hip before undergoing left hip replacement surgery on 25 October 2017.
17.	In April 2016, the applicant travelled to Sydney to attend a concert. During that trip, the applicant started noticing a niggle in his right groin/hip. On the flight home, the applicant experienced swelling over the whole lower right side of his body, causing discomfort.
18.	The applicant was concerned and consulted his general practitioner in mid-May 2016. A procedure was performed to drain fluid from the applicant’s groin.
19.	In the lead up to the left hip replacement surgery in October 2017, the applicant had increased pain and limited range of movement in the left leg. The applicant stated:
“This made it difficult for me to walk at times as I was taking smaller strides than normal with my left leg. This had the impact of me walking with a limp and relying more on my right-hand side. 
I recall during this period, being April 2016 to October 2017 the pain in my right hip gradually increased and I had swelling in my lower limbs and groin from time to time. This pain increased as the pain, disability and limited movement in my left leg also increased.”
20.	The applicant said he recalled being advised by his general practitioner and physiotherapist that the pain and symptoms in his right hip were secondary to the problems with his left hip. The focus of treatment was the applicant’s left hip and the applicant recalled thinking that if the left hip got sorted, hopefully the right hip pain would go away.
21.	The applicant continued, however, to modify the way he was walking and found himself overcompensating on the right-hand side when he walked. The applicant recalled reporting pain at his right hip to his physiotherapist and undergoing imaging in about September 2018.
22.	The applicant’s right sided hip and groin pain began to impact on the applicant’s activities of daily living and limit his ability to perform physiotherapy exercises for his left hip.
23.	In early 2019, the applicant’s general practitioner referred him for an MRI scan and the applicant was seen by his specialist, Dr Khoury. The applicant continued to report his right hip pain to his general practitioner and physiotherapist.
24.	The applicant gave a detailed description of the symptoms at his right hip.
Applicant’s other evidence and submissions
25.	In oral submissions given at the arbitration hearing on 24 October 2022, the applicant noted his statement evidence with regard to his left hip injuries and the onset of a limp.
26.	The Commission was referred to a letter of referral prepared by the applicant’s general practitioner, Dr Michael Kuzeff, to orthopaedic surgeon, Dr Elie Khoury, dated 21 January 2019, for an opinion in relation to increasing pain in the right hip since about 2017. The letter queried whether the symptoms were related to the left hip.
27.	The applicant referred to radiological evidence, including the report of an MRI scan of the right hip performed on 7 January 2019 which described an anterior superior labral tear and features of mild to moderate degenerative change with diffuse thinning of the articular cartilage.
28.	X-rays of the right hip had been performed in 2017 and 2018.
29.	The applicant submitted that the notes of his general practitioner recorded the onset of symptoms in the right hip. On 22 October 2018, for example, Dr Kuzeff recorded a note as follows:
“c/o ongoing right hip pain. 
?related to changed biomechanics. 
Seeing physio.”

30.	The applicant referred to a report prepared by his orthopaedic surgeon, Dr Parminder Singh, for his solicitors on 18 May 2022. The applicant said Dr Singh neatly dissected the case and give an opinion on causation as follows:
“In my opinion, prior to and following left hip replacement surgery, one does put more pressure on the nonoperated side right hip. Prior to the surgery, if Ross was struggling with walking and was limping as a result of the pain in the left hip, this would have put additional stress on the right hip in order to compensate. In addition, during the first few weeks following surgery, the right hip would compensate for the left hip surgery until the gluteal muscles of the left hip are able to take the weight of the body without the aid of crutches. Whilst recovering from the total hip replacement, Mr Mann would have been using crutches to share the load up until the left hip was able to take the weight unaided. Furthermore, research has shown the demand on the musculature would be greatest from the sitting to standing position and the standing to sitting transitions. (Talis et al 2008, Eng and Chu 2002, Cheng et al 2014). With this in mind, it is plausible that the right hip pathology was aggravated by the left hip condition.”
31.	Dr Singh expressed agreement with an opinion on causation expressed by the applicant’s medico-legal expert, orthopaedic surgeon, Dr Eugene Gehr, in a report dated 29 January 2020. Dr Singh explained:
“In my opinion, there was an underlying cam lesion. This has been present since Mr Mann reached skeletal maturity. The labral tear may have been caused by the increased load demanded on the right hip leading to an altered gait for the reasons mentioned above. In addition, further stress would have been put on the right hip from sitting to standing and standing to sitting. This could also have increased the likelihood of tearing the acetabular labrum and caused the need for a right hip arthroscopy.”
32.	On examination of the applicant, Dr Gehr had noted that the applicant used a walking aid and walked with an antalgic limp referred to the right hip. Dr Gehr gave the opinion:
“The right hip injury has risen as a consequence of the injuries of 19/11/2004 and 28/6/2010. It is often discussed at medicolegal meetings the role of the contralateral joint, such as a shoulder joint or in this case a hip joint as a result of an injury. He clearly had injuries to the left hip with documentations and accepted by the relevant authorities and is not unreasonable that the problems with the right hip rose as a consequence of the problems with his left hip. It is accepted in the general medicolegal literature that the incidence of problems arising over the contralateral hip range anywhere from 20% to 60%. This is the result of increased loads being placed on the contralateral joint.”
33.	The applicant submitted that weighing against his medical evidence was a tepid opinion from the respondent’s medico-legal expert, Dr Graeme Doig, dated 13 December 2019. The applicant submitted that Dr Doig had ventured a view that the proposed surgery was probably appropriate. In relation to causation, Dr Doig essentially said that he was unable to identify scientific evidence indicating that pathology in one lower limb caused problems in the contralateral limb.
34.	The applicant submitted that Dr Doig’s comment was contradicted by the literature relied upon by the applicant’s doctors and was out of step with both their opinions, the applicant’s statement evidence about what he experienced as his limp worsened and a large number of cases in the Commission.
35.	Putting aside the opinion from Dr Doig, there was nothing left but the applicant’s evidence. The applicant submitted that Dr Doig’s opinion ought to be put to one side because he had not explained his opinion. Dr Doig also appeared focused on the question of whether there was an injury to the right hip rather than a consequential condition.
36.	The applicant referred the Commission to the cases of Moon v Conmahand Kooragang Cement Pty Ltd v Bates with regard to the relevant legal tests to be applied.
Respondent’s evidence and submissions
37.	The respondent noted that the applicant had sustained separate frank injuries to the left hip, liability for which was not in dispute. The question for the Commission was whether, as a result of either or both of those injuries, there was a consequential condition at the right hip.
38.	The respondent submitted that acceptance of the applicant’s doctors’ opinions was predicated upon the accuracy of the history provided by the applicant. The respondent submitted that there were issues with regard to the reliability of the applicant’s evidence as to the onset of symptoms in the right hip. The respondent submitted that the Commission would not be satisfied, on the balance of probabilities that causation had been established.
39.	The respondent submitted that the report of Dr Doig ought to be read as a whole. Dr Doig opined that the applicant suffered from degenerative osteoarthritis to the right hip joint. Effectively, Dr Doig opined that the applicant had not sustained a consequential condition, related to the left hip injuries and there was no isolated injury to the right hip. The respondent submitted that Dr Doig’s opinion would be accepted.
40.	The respondent referred to notes from the applicant’s physiotherapist and observed that in an entry dated 24 February 2014, the applicant reported right hip symptoms. No opinion had been provided by the physiotherapist with respect to causation. Simply reporting symptoms was not adequate to establish causation.
41.	Similarly, although there were references to the applicant’s right hip in the general practitioner’s notes, no opinion on causation had been provided by the applicant’s general practitioner.
42.	The respondent noted a clinical record made on 8 April 2013, which stated:
“…today main problem is that of pain management, the hip pain is intense, He is to see Dr Singh for review next month. Yesterday mowed the lawns, now quite intense pain. 
He worked back in september last years, but after 2 weeks his hip pain had recurred quite severely, pain in right in the groin. Twinge in his buttock.”
43.	The respondent observed that there was no suggestion in the clinical record that the left hip injury was the cause of the applicant’s right groin pain.
44.	The respondent also referred to an entry in the clinical records dated 28 September 2018 which stated:
“Big dog jumped up on him about 2 weeks ago and stirred up his 
Recently was assessed by another specialist in Sydney. 
Getting some right hip pain too. Apparently has some earlier changes of OA on imaging right hip.”
45.	The respondent submitted that this clinical record suggested right hip symptoms in the context of an event involving a dog. There was no suggestion from the general practitioner that the applicant’s left hip was involved.
46.	Although the clinical note on 22 October 2018 to which the applicant had referred related right hip symptoms to the left hip, the respondent submitted that the applicant had already been complaining of right hip issues. Notwithstanding what was recorded by Dr Kuzeff in that entry, given the passage of time and evidence of prior issues in the right hip without reference to the left hip, the Commission would not be satisfied that the applicant had sustained a consequential right hip condition.
47.	The respondent also referred to the earlier reports from Dr Singh and noted that the applicant initially appeared to have reported to Dr Singh that he had sustained frank injuries to both hips at the time of the original injurious events. Dr Singh’s opinion with regard to a consequential condition in his report of 18 May 2022 was only provided after the intervention of the applicant’s solicitors.
48.	In a report dated 14 August 2021, Dr Singh gave the opinion:
“In my opinion right hip had an underlying cam lesion at the level of the femoral head neck junction. This cam lesion has been present since he reached skeletal maturity. If Mr Mann's right hip was force into deep hip flexion and rotation during his original injuries in 2004 and 2010, Mr Mann's right hip on the balance of probabilities could have sustained a traumatic labral tear.”
49.	The respondent submitted that there was a difficulty with the applicant’s history in relation to whether he sustained a frank injury to the right hip or a consequential condition. The history provided to Dr Singh was inconsistent with the history provided to the medicolegal doctors and the applicant’s lay evidence.
50.	Dr Singh’s revised opinion was predicated upon the history provided to him. From his other reports, it could be seen that the history provided to Dr Singh by the applicant’s solicitors had changed from that he obtained whilst treating the applicant.
51.	Examining the evidence as a whole, the respondent submitted that the Commission would not be satisfied that the applicant had sustained a consequential condition on the balance of probabilities.
Applicant’s submissions in reply
52.	The applicant submitted that the respondent’s attempt to poke holes in the histories given to various doctors was contrary to the approach in Mason v Demasi.
53.	The applicant had given his account in a sworn statement. That statement was consistent with the histories provided to the medico-legal experts. The Commission would not rely on any apparent inconsistency in Dr Singh’s treating evidence to suggest that the applicant had been dishonest. The only inconsistency appeared in the reports from Dr Singh. The better proposition was that Dr Singh made a mistake. The applicant had given the same history to multiple doctors.
FINDINGS AND REASONS 
54.	Section 9 of the 1987 Act provides that a worker who has received an “injury” shall receive compensation from the worker’s employer. The term “injury” is defined in s 4 of the 1987 Act as follows:
“4 Definition of ‘injury’ 
In this Act:
injury:
(a) 	means personal injury arising out of or in the course of employment,
(b) 	includes a disease injury, which means:
(i) 	a disease that is contracted by a worker in the course of employment but only if the employment was the main contributing factor to contracting the disease, and
(ii) 	the aggravation, acceleration, exacerbation or deterioration in the course of employment of any disease, but only if the employment was the main contributing factor to the aggravation, acceleration, exacerbation or deterioration of the disease, and
(c) 	does not include (except in the case of a worker employed in or about a mine) a dust disease, as defined by the Workers’ Compensation (Dust Diseases) Act 1942, or the aggravation, acceleration, exacerbation or deterioration of a dust disease, as so defined.”
55.	The applicant in these proceedings has accepted “injuries” to his left hip and relies on a consequential condition at the right hip resulting from those injuries.
56.	The test for establishing a consequential condition can be distinguished from that required to establish an “injury”. In this regard, the comments of Deputy President Roche in Moon v Conmah at [45]-[46] are relevant:
“It is therefore not necessary for Mr Moon to establish that he suffered an ‘injury’ to his left shoulder within the meaning of that term in section 4 of the 1987 Act. All he has to establish is that the symptoms and restrictions in his left shoulder have resulted from his right shoulder injury. Therefore, to the extent that the Arbitrator and Dr Huntsdale approached the matter on the basis that Mr Moon had to establish that he sustained an ‘injury’ to his left shoulder in the course of his employment with Conmah they asked the wrong question.”
57.	In Bouchmouni v Bakhos Matta t/as Western Red Services, Roche DP commented, 
“The Commission has considered and explained the difference between an ‘injury’ and a condition that has resulted from an injury in several recent decisions (Moon v Conmah Pty Ltd [2009] NSWWCCPD 134 at [43], [45] and [50] (Moon); Superior Formwork Pty Ltd v Livaja [2009] NSWWCCPD 158 at [122]; Cadbury Schweppes Pty Ltd v Davis [2011] NSWWCCPD 4 at [28]–[32] and [39]–[42] (Davis); North Coast Area Health Service v Felstead [2011] NSWWCCPD 51 at [84]; Australian Traineeship System v Turner [2012] NSWWCCPD 4 at [28] and [29] (Turner); Kumar v Royal Comfort Bedding Pty Ltd [2012] NSWWCCPD 8 at [35]–[49] and [61]). … 
The injury to Mr Bouchmouni’s right knee caused him to seek treatment in the form of surgery and physiotherapy. The evidence suggests that it was in the course of receiving that treatment, and/or as a result of an altered gait because of his knee symptoms, Mr Bouchmouni developed back symptoms. If that is accepted, and no reason has been advanced why it should not be, it is clear beyond doubt that his back condition has resulted from the treatment he received for his accepted knee injury and his altered gait. That does not, however, make the back condition an ‘injury’.”
58.	In Trustees of the Roman Catholic Church for the Diocese of Parramatta v Brennan Snell DP referred to the decisions in Moon v Conmah and Kumar v Royal Comfort Bedding and observed:
“The above do not suggest any need that a finding of a consequential condition necessarily involves the identification of pathology. It is sufficient to find (if the evidence supports it) a condition that results from an employment injury. I accept the respondent’s submission that it is sufficient to find a consequential condition, pathology need not necessarily be identified.”
59.	A commonsense evaluation of the causal chain is required. The legal test of causation is that discussed by the Court of Appeal in Kooragang Cement Pty Ltd v Bates, where Kirby P said at [461] (Sheller and Powell JJA agreeing): 
“From the earliest days of compensation legislation, it has been recognised that causation is not always direct and immediate…
Since that time, it has been well recognised in this jurisdiction that an injury can set in train a series of events. If the chain is unbroken and provides the relevant causative explanation of the incapacity or death from which the claim comes, it will be open to the Compensation Court to award compensation under the Act.” 
60.	His Honour said at [463]-[464]: 
“The result of the cases is that each case where causation is in issue in a workers’ compensation claim, must be determined on its own facts. Whether death or incapacity results from a relevant work injury is a question of fact. The importation of notions of proximate cause by the use of the phrase ‘results from’, is not now accepted. By the same token, the mere proof that certain events occurred which predisposed a worker to subsequent injury or death, will not, of itself, be sufficient to establish that such incapacity or death ‘results from’ a work injury. What is required is a commonsense evaluation of the causal chain. As the early cases demonstrate, the mere passage of time between a work incident and subsequent incapacity or death, is not determinative of the entitlement to compensation. In each case, the question whether the incapacity or death ‘results from’ the impugned work injury (or in the event of a disease, the relevant aggravation of the disease), is a question of fact to be determined on the basis of the evidence, including, where applicable, expert opinions. Applying the second principle which Hart and Honoré identify, a point will sometimes be reached where the link in the chain of causation becomes so attenuated that, for legal purposes, it will be held that the causative connection has been snapped. This may be explained in terms of the happening of a novus actus. Or it may be explained in terms of want of sufficient connection. But in each case, the judge deciding the matter, will do well to return, as McHugh JA advised, to the statutory formula and to ask the question whether the disputed incapacity or death ‘resulted from’ the work injury which is impugned.” 
61.	It is the applicant who bears the onus of establishing on the balance of probabilities that he sustained a consequential condition affecting his right hip. In Nguyen v Cosmopolitan Homes (NSW) Pty Limited McDougall J stated at [44]: 
“A number of cases, of high authority, insist that for a tribunal of fact to be satisfied, on the balance of probabilities, of the existence of a fact, it must feel an actual persuasion of the existence of that fact. See Dixon J in Briginshaw v Briginshaw [1938] HCA 34; (1938) 60 CLR 336. His Honour’s statement was approved by the majority (Dixon, Evatt and McTiernan JJ) in Helton v Allen [1940] HCA 20; (1940) 63 CLR 691 at 712.”
62.	The lay and medical evidence in this case reveals that the applicant experienced ongoing symptoms at his left hip following the injuries in 2004 and 2010.
63.	A Medical Assessment Certificate issued by Approved Medical Specialist, Dr Geoffrey Stubbs on 7 October 2014 in Workers Compensation Commission proceedings for lump sum compensation described, for example, the applicant’s present symptoms as including an aching, groin discomfort which increased with immobility and was associated with increasing stiffness around the hip. Dr Stubbs described marked muscle wasting on the left side, a short stance phase, antalgic limp and a positive Trendelenberg fatigue sign. It was noted that the applicant did not usually use a walking aid.
64.	The applicant came to a total left hip replacement performed by Dr Khoury on 25 October 2017. In a report prepared for the insurer in relation to the total hip replacement, dated 3 May 2017, Dr Khoury confirmed that after an arthroscopy in 2012, the applicant’s condition had deteriorated to the point that he was unable to walk more than a kilometre. Dr Khoury noted that the applicant limped.
65.	Regular references to symptoms of pain, restriction and limping or antalgic gait can be found in the clinical records of the applicant’s general practitioner and physiotherapist. A clinical note recorded by Dr Aletta Mphisa on 10 November 2016, for example, described findings on examination including:
“antalgic gait 
Cannot put full weight on left hip 
ROM severely limited by pain in all directions”
66.	The medical evidence is therefore consistent with the applicant’s claim that due to pain and restriction at his left hip, he developed a limp and relied more on his right-hand side.
67.	Although the applicant described a particular worsening of right hip symptoms following a trip to Sydney in 2016, as the respondent has noted there are references to right hip or groin pain in the clinical records from 2013 onwards. 
68.	The respondent is also correct in noting that the clinical records in 2013 and 2014 did not specifically link the reported right hip symptoms to the left hip injury. The symptoms were, however, reported in the context of issues the applicant was experiencing with, and ongoing treatment of, his left hip.
69.	Complaints of symptoms and investigations of the applicant’s right hip are more consistently recorded in the treating medical evidence in the period from 2017 onwards.
70.	I accept that the letter of referral prepared by Dr Kuzeff to Dr Khoury on 21 January 2019 and the clinical record recorded earlier by Dr Kuzeff on 22 October 2018, suggest that Dr Kuzeff was of the opinion that the symptoms in the applicant’s right hip were causally related to the difficulties with the applicant’s left hip. Although no report or reasoned opinion on causation has been provided by Dr Kuzeff, these records form part of the overall body evidence relevant to the Commission’s determination. These indications of a possible causal connection to the left hip and altered biomechanics are consistent with the opinions eventually provided by Dr Singh and Dr Gehr.
71.	The respondent’s submissions placed considerable emphasis on a potential inconsistency in the history recorded by Dr Singh in relation to the onset of right hip symptoms.
72.	Dr Singh first saw the applicant in relation to his right hip on 3 May 2019. Dr Singh had, however, seen the applicant previously in relation to his left hip. In the report dated 3 May 2019, Dr Singh took a history of two years of intermittent right groin pain. Dr Singh referred to the injurious events in 2004 and 2010 and stated:
“He reported he had hip symptoms since this injury. Initially the left hip was sore and more recently the right hip began so.”
73.	In response to questions from the insurer, Dr Singh provided a similar history, stating:
“Patient reports he slipped through a roof in 2004. Injuring his left hip. Patient reports over the last 2 years his right hip pain has got worse. If his hip has been forced into flexion, adduction and internal rotation or flexion abductors external rotation, this can lead to hip pain especially if there have been repetitive movements.”
74.	In a report prepared for the applicant’s solicitors dated 14 August 2021, however, Dr Singh described a history of injury to both hips at the time of the original injurious events. Dr Singh noted that this was inconsistent with what had been reported to Dr Doig.
75.	That history was amended in a report dated 18 May 2022. The applicant’s solicitors’ instructions to Dr Singh in preparing that report indicate that the applicant denied any trauma to the right hip directly in the injurious events and gave an account of developing right hip symptoms as a consequence of developing an altered gait to protect his left hip.
76.	I have approached the inconsistencies in Dr Singh’s reports with caution. In Mason v Demasi, Basten JA stated: 
“First, the trial judge was invited to discount the appellant’s oral testimony on the basis of accounts given to various health professionals, which appeared inconsistent either with each other, or with her oral testimony, or both. The difficulties attending this kind of exercise should be well understood; as explained in Container Terminals Australia Ltd v Huseyin [2008] NSWCA 320 at [8], such apparent inconsistencies may, and often should, be approached with caution for the following reasons, amongst others: 
(a)	 the health professional who took the history has not been cross-examined about: 
(i)	the circumstances of the consultation; 
(ii)	the manner in which the history was obtained; 
(iii)	the period of time devoted to that exercise, and 
(iv)	the accuracy of the recording; 
(b) 	the fact that the history was probably taken in furtherance of a purpose which differed from the forensic exercise in the course of which it was being deployed in the proceedings; 
(c) 	the record did not identify any questions which may have elucidated replies; 
(d) 	the record is likely to be a summary prepared by the health professional, rather than a verbatim recording, and 
(e) 	a range of factors, including fluency in English, the professional’s knowledge of the background circumstances of the incident and the patient’s understanding of the purpose of the questioning, which will each affect the content of the history.”
77.	There is no indication elsewhere in the voluminous body of treating material before the Commission that the applicant complained of symptoms at his right hip at the time of the events in 2004 and 2010. The first and only suggestion of a traumatic injury to the right hip in those events appears in the report of Dr Singh, dated 14 August 2021.
78.	The history recorded by Dr Singh in that report is not entirely consistent with his earlier treating reports. In those reports. Dr Singh had described only an injury to the left hip with intermittent symptoms at the right hip commencing in or around 2017.
79.	This was consistent with the history documented in the other treating medical evidence and reported to both the applicant’s medico-legal expert, and the respondent’s medico-legal expert, Dr Doig. It is also consistent with the account recorded by the applicant in his statement evidence.
80.	In considering the evidence as a whole, therefore, I accept the applicant’s submission that the history recorded in Dr Singh’s report of 14 August 2021 should be treated as an error on the part of Dr Singh. That inconsistency does not, in my opinion, outweigh the otherwise consistent body of evidence regarding the onset of symptoms at the applicant’s right hip.
81.	There is nothing in the evidence before me to suggest any intervening event was causative of right hip symptoms. In all the circumstances, I am satisfied that the history provided to Dr Gehr, and ultimately to Dr Singh at the time of his most recent report, was sufficiently accurate and reliable as to provide a proper foundation for the opinions on causation expressed therein.
82.	Both Dr Singh, in his most recent report, and Dr Gehr have provided clear and reasoned opinions explaining that the symptoms at the right hip resulted from increased loads being placed on the contralateral joint due to the symptoms and restrictions at the injured left hip. Those opinions are consistent with the suggestions in Dr Kuzeff’s evidence that the right hip symptoms arose due to altered biomechanics at the left hip.
83.	Weighing against the applicant’s evidence is the report from the respondent’s medico-legal expert, Dr Doig. Dr Doig took a history that was consistent with those ultimately relied on by Dr Singh and Dr Gehr.
84.	Dr Doig also made a diagnosis that was broadly consistent with those made by the applicant’s doctors, referring to osteoarthritis of the right hip joint and possibly a degenerative labral tear. Dr Doig did, however, describe this diagnosis as “idiopathic”. 
85.	In explaining this view, Dr Doig said there was no isolated injury to the right hip in 2004 or otherwise. 
86.	Insofar as the applicant suggested a consequential condition at the right hip as a result of the left hip injury, Dr Doig stated,
“I am unable to supply any scientific evidence indicating that pathology in the lower limb causes problems on the contra-lateral side in the absence of a long-standing leg-length discrepancy, weakness or arthrodesis.”
87.	As noted by the applicant’s submissions, however, Dr Singh was able to refer to scientific research in support of his opinion. Dr Doig’s opinion failed to engage with the clear history of antalgic gait or limp and difficulty weight-bearing or the gradual onset of right hip symptoms in this context. Dr Doig’s opinion also goes against the weight of medical opinion in the evidence before me.
88.	Insofar as there may have been pre-existing, idiopathic or degenerative pathology in the right hip, that circumstance is not inconsistent with the applicant’s case. Dr Singh, for example, referred to the likelihood that there was a cam lesion present since the applicant reached skeletal maturity. Dr Singh accepted, however, that the labral tear was caused or accelerated by the increased load placed on the applicant’s right hip due to his left hip injuries.
89.	It is trite law that a condition can have more than one cause and yet be compensable. In Murphy v Allity Management Services Pty Ltd Roche DP stated: 
“[57] 	…That is because a condition can have multiple causes (Migge v Wormald Bros Industries Ltd (1973) 47 ALJR 236; Pyrmont Publishing Co Pty Ltd v Peters (1972) 46 WCR 27; Cluff v Dorahy Bros (Wholesale) Pty Ltd (1979) 53 WCR 167; ACQ Pty Ltd v Cook [2009] HCA 28 at [25] and [27]; [2009] HCA 28; 237 CLR 656). The work injury does not have to be the only, or even a substantial, cause of the need for the relevant treatment before the cost of that treatment is recoverable under s 60 of the 1987 Act. 
[58] 	Ms Murphy only has to establish, applying the commonsense test of causation (Kooragang Cement Pty Ltd v Bates (1994) 35 NSWLR 452; 10 NSWCCR 796), that the treatment is reasonably necessary ‘as a result of’ the injury (see Taxis Combined Services (Victoria) Pty Ltd v Schokman [2014] NSWWCCPD 18 at [40]–[55]). That is, she has to establish that the injury materially contributed to the need for the surgery (see the discussion on the test of causation in Sutherland Shire Council v Baltica General Insurance Co Ltd (1996) 12 NSWCCR 716).”
90.	Having carefully considered all of the evidence, I am satisfied that the applicant has sustained a consequential condition at the right hip as a result of the injuries to his left hip. I am further satisfied that the injuries to the applicant’s left hip have materially contributed to the present need for surgery as recommended by Dr Singh.
91.	There is no longer any dispute between the parties as to whether the procedure proposed by Dr Singh is appropriate and reasonably necessary medical treatment for the applicant’s right hip condition.
92.	It follows that I am satisfied for the purposes of s 60 of the 1987 Act that the surgery proposed by Dr Singh is reasonably necessary as a result of the injuries to the applicant’s left hip on 19 November 2004 and 28 June 2010.
93.	There will be an order for the respondent to pay the costs of and incidental to the proposed medical treatment.