Sheahan v Springmount Property Services Pty Ltd

CERTIFICATE OF DETERMINATION OF MEMBER
CITATION:	Sheahan v Springmount Property Services Pty Ltd [2021] NSWPIC 421
APPLICANT:	Paul Sheahan
RESPONDENT:	Springmount Property Services Pty Ltd
MEMBER:	Rachel Homan
DATE OF DECISION:	20 October 2021
CATCHWORDS:	WORKERS COMPENSATION - Claim for lump sum compensation; injury to left knee accepted; whether consequential condition at right knee as a result; extensive history of prior injury and symptoms resulting in surgery to both knees; whether effects of left knee injury had ceased; onset of symptoms in right knee when twisting and turning; whether evidentiary onus discharged; Held - applicant sustained a consequential right knee condition; matter remitted to President for referral to a Medical Assessor to assess left knee injury and right knee consequential condition.
DETERMINATIONS MADE:	1. The applicant sustained a consequential right knee condition as a result of the injury to his left knee on 28 December 2015. 2. The matter is remitted to the President for referral to a Medical Assessor as follows: Date of injury: 28 December 2015 Body Parts: Left lower extremity (knee) Right lower extremity (knee) - consequential Method: Whole Person Impairment 3. The materials to be referred to the Medical Assessor are to include: (a) Application to Resolve a Dispute and all attachments other than the report of Associate Professor Michael Ryan, dated 31 May 2021; (b) Reply and attached documents; (c) documents attached to an Application to Admit Late Documents lodged by the applicant on 13 September 2021, and (d) chronology lodged by the applicant on 20 September 2021.

STATEMENT OF REASONS

BACKGROUND

Mr Paul Sheahan (the applicant) was employed by Springmount Property Services Pty Ltd (the respondent) when he sustained an injury to his left knee caused by jumping from a street sweeping machine on 28 December 2015. Liability for the left knee injury is not in dispute.
On 10 June 2021, the applicant made a claim for lump sum compensation pursuant to s 66 of the Workers Compensation Act 1987 (the 1987 Act) in reliance upon an assessment of 33% whole person impairment (WPI) made by Dr Christopher Oates. That assessment included a degree of permanent impairment at the right knee due to a consequential condition.
On 11 August 2021, the respondent’s insurer issued a notice pursuant to s 78 of the Workplace Injury Management and Workers Compensation Act 1998 (the 1998 Act). The insurer determined that the effects of the left knee injury had ceased; there was no injury or consequential condition at the right knee; and no permanent impairment had resulted from the injury on 28 December 2015.
The present proceedings were commenced by an Application to Resolve a Dispute (ARD) lodged in the Commission on 18 August 2021. The applicant seeks lump sum compensation in accordance with the assessment of Dr Oates.

PROCEDURE BEFORE THE COMMISSION

The parties appeared for conciliation conference and arbitration hearing via teleconference on 20 September 201. The applicant was represented by Mr Dan Steiner of counsel, instructed by Mr Joel Francis. The respondent was represented by Mr Stephen Harris. A representative from the insurer was also present.
During the conciliation phase, it was agreed that the injury to the left knee was not in dispute and was capable of referral to a Medical Assessor to assess the degree of permanent impairment resulting from the injury.
The applicant elected to rely on the reports of Dr Oates to the exclusion of a report by Associate Professor Ryan for the purposes of cl 44 of the Workers Compensation Regulation 2016. Late documents lodged by the applicant on 13 and 20 September 2021 were admitted in the proceedings.
The applicant was granted leave to amend the date of a previous injury to his right knee described at p 8 paragraph 27 of his written statement and in the applicant’s chronology to “April 2014”.
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

10.The parties agree that the following issues remain in dispute:

(a) whether the applicant sustained a consequential right knee condition as a result of the injury to his left knee on 28 December 2015, and
(b) the degree of permanent impairment resulting from the injury on 28 December 2015.

EVIDENCE

Documentary Evidence

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

(a)    ARD and all attachments other than the report of Associate Professor Michael Ryan, dated 31 May 2021;
(b)    Reply and attached documents;
(c)    documents attached to an Application to Admit Late Documents lodged by the applicant on 13 September 2021, and
(d)    chronology lodged by the applicant on 20 September 2021.

Neither party applied to adduce oral evidence or cross-examine any witness.

Applicant’s evidence

The applicant’s evidence is set out in a written statement made by him on 25 February 2017.
The applicant described a number of previous physical injuries including a broken left tibia in 1986. The injury healed and the applicant went on to play first grade rugby league between 1982 and 1990. The applicant was very active in beach sports and surfing from the time he finished playing football. The applicant engaged in weightlifting and was able to dead lift and squat 200 kg.

In November 2007, the applicant injured his left knee when launching from the starting blocks in a beach sprint race. The applicant was referred to orthopaedic surgeon, Dr Phil Allen, and underwent surgery on 3 March 2008.
In early 2008, the applicant’s left knee was injured whilst surfing.
In late 2009, the applicant developed soreness in his right big toe when running and walking. The applicant eventually proceeded to a fusion of the first metatarsophalangeal joint on
1 September 2010. The applicant had an excellent outcome from that procedure and was able to return to surfing and other exercise.

In February 2011, the applicant injured his left knee whilst surfing. The applicant was diagnosed by Dr Allen as having a torn meniscus. The applicant proceeded to an arthroscopic resection of the left knee. The applicant had a good outcome from that surgery and returned to running, surfing and weight training.
In July 2011, the applicant underwent a fusion to his left big toe. Surgery to the second left toe was performed on 27 August 2012.
In April 2014, the applicant injured his right knee whilst competing in the Australian surf titles. The applicant was sprinting on sand when he hit a hole. The applicant proceeded to an arthroscopy of the right knee under the Queensland workers compensation scheme. The applicant took around six weeks to recover and then was fully fit.
With regard to the effects of the work injury on 28 December 2015, the applicant stated:
“Since the motor vehicle accident on 28 December 2015, I favoured my left knee. When I walk, I limp and I try not to put any weight on my left knee. I felt that this was putting a lot of weight and pressure on my right knee. I recall specifically that I turned and twisted one day in November 2016, and felt a little twinge in my right knee and since that time, my right knee has been causing me grief also. When I walk upstairs or stand up from a seated position, I apply more pressure on my right leg and right knee, due to the pain I've been in since 28 December 2015 in my left knee. This is now causing significant discomfort in my right knee.”
The applicant described the circumstances of the injury on 28 December 2015. The applicant was driving a street sweeper machine down a carpark traffic ramp from the first storey to ground level when he had to negotiate a speedbump at approximately 5 to 10 km/h. As he went over the speedbump, the accelerator became stuck and the vehicle continued onward with acceleration off the bottom of the ramp and onto the flat ground. The applicant tried to brake the machine but the brake appeared to spongy and lifeless. The applicant was able to push the pedal all the way to the floor but nothing happened.
The machine accelerated forward for approximately 40 m. Despite turning the key, the engine would not turn off. After hitting a second speedbump at about 30 km an hour the machine began to wobble and the applicant was concerned it was going to tip over or throw him off.
Seeing the machine approach a wall at speed, the applicant jumped at an approximate 45° angle from the moving machine. The applicant tried to land on his feet but the speed and momentum forced him forward and onto his left knee and then left elbow, finally hitting his head on the ground. The applicant felt immediate sharp pain in his left knee, left elbow, head (jaw) and lower back.
The applicant attended his regular general practitioner, Dr Brickley, and was provided with an initial workers compensation certificate of capacity. The applicant returned to work on 5 January 2016 but continued with pain and discomfort in the left knee, swelling and lack of mobility. The applicant ceased work after a meeting the following day in which he was accused of poor work performance and causing deliberate damage to the street sweeper.
From about February 2019, the applicant commenced a casual job at Coles packing shelves for approximately 12 hours per week. The job only lasted three or so months because the pain in the applicant’s knee was too much.

Treating evidence

On 13 May 2014, orthopaedic surgeon, Dr Philip Allen prepared report in relation to a recent injury to the applicant’s right foot and knee. The injury was said to have occurred as follows:
“At the time of his injury he was taking part in a surf life saving event and fell in a hole whilst sprinting at the Australian surf titles. He sustained a twisting injury to his right knee and an injury to his right foot.”
Dr Allen recorded his findings on examination:
“As far as his right knee is concerned, he does have some degenerative changes in the medial compartment of the right knee and now has a torn meniscus posteriorly with associated bone bruising indicating the site of a recent injury. This is confirmed on clinical examination and MRI scan.”
Dr Allen recommended an arthroscopic resection of the meniscal tear.
An operation report prepared by Dr Allen records that on 22 May 2014, the applicant underwent an arthroscopy of the right knee with resection of a lateral meniscal tear and medial meniscal tear and debridement.
At a review on 3 June 2014, Dr Allen reported:
“I have reviewed Paul again today following his knee surgery and I am happy to report that he has had significant benefit from his recent surgery. I have discussed the findings with him at length today including the damage that he has to the articular surface and have advised him against doing a lot of running in the future. He has already made this decision himself and he will concentrate more on swimming, surfing and cycling for his fitness training.”
On 13 June 2014, Dr Allen reported that he had seen the applicant again as he was a little tender around the medial arthroscopic port where there was some post-operative swelling. The applicant also had some pain over the medial joint line. Dr Allen examined the knee and considered that there was no cause for any concern. The symptoms were coming from internal derangement inside the knee where the applicant had significant articular disease on the medial compartment.
On 15 July 2014, Dr Allen reported:
“Paul has come to see me today as he had a bit of an ache in his knee when he was doing a long drive last weekend. He drove all the way down to Angourie to take some photographs and had some aching in the medial aspect of his knee on return. It is a long drive and his symptoms are not unexpected given his condition. His knee has now settled down completely and he needed little else than a simple analgesia at that time.”
Dr Allen said the applicant was very happy with how the knee was and he considered there should be no impediment to him returning to his normal activities.
On 14 March 2016, Dr Allen prepared a report for the applicant’s general practitioner in relation to the injury on 28 December 2015:
“As he came off the machine he struck the superoloteral aspect of his left knee on the ground. There was a graze in this area. He continues to have pain in this area and now has ongoing discomfort behind the left patella. He feels as if the patella is not tracking normally and has significant pain when heading up or down slopes. He has swelling in the knee and the symptoms are with him on a daily basis. They are interfering significantly with his activities of daily living and making it uncomfortable for him to get around.
On examination there is a small effusion in the knee today and patellofemoral crepitus affecting both the left and right knee. It is worse on the left. There is tenderness around the lateral aspect of the left patella and the proximal aspect of the lateral tibial plateau. Meniscal provocative tests are negative and the knee appears stable.”
After reviewing the results of an MRI scan, Dr Allen reported on 22 March 2016 that the applicant had sustained a significant injury to the left knee. There was a chondral contusion over the medial femoral condyle with evidence of cartilage loss in that area. There was associated bruising. In the lateral compartment there was further damage and maceration of the lateral meniscus which was frayed, unstable and currently symptomatic. Given the severity of symptoms, Dr Allen recommended an arthroscopy of the left knee.
An operation report indicates that on 24 May 2016, an arthroscopy of the left knee was performed.
On 9 June 2016, Dr Allen reported that it would take up to six weeks for the applicant’s knee to recover. Dr Allen noted that lateral compartment damage takes much longer than a medial meniscal tear to recover after arthroscopy.
Clinical records made by the applicant’s general practitioner on 23 June 2016 noted:
“Review LEFT knee -arthroscopic repair~ 3 weeks ago 31/5/2016
still limping - feels the knee still locks at times”
On 7 July 2016, Dr Allen reviewed the applicant and reported:
“His left knee has settled down quite significantly now and on examination today he has an excellent range of motion and no effusion. It has been a long haul for him as it often is with lateral compartment damage.
At this point I think he is ready to return to some light duties but he should not return to heavy manual work for another few weeks. There was extensive damage in the articular cartilage and it would be better if he had a gradual return to work rather than abruptly beginning heavy manual work.”
Clinical notes recorded by the applicant’s general practitioner in August and September 2016 referred to swelling and pain at the left knee.
A letter of referral to orthopaedic surgeon, Dr Paul Mednis, dated 21 December 2016 sought assessment and management of right knee pain. The applicant’s general practitioner, Dr Ian Mitchell, provided a history as follows:
“Paul had an accident at work on 28 December 2015 where he had to jump from the street sweeping vehicle he was operating. On that occasion he injured his left knee and apparently suffered a torn left medial meniscus. Since that he has been favouring his left knee and right knee pain has occurred in the last month.”
On 14 February 2017, the applicant was seen by orthopaedic surgeon, Dr David Liu. Dr Liu noted that the applicant presented with ongoing pain in the left and right knees due to patellofemoral overload and secondary bone bruising as well as a degenerative medial meniscal tear in the right knee.
Dr Liu took a history of the injury in December 2015 and the subsequent arthroscopy performed to the left knee by Dr Allen. The knee never settled and was now in fact worse. As a result of favouring the left knee, the right knee was aggravated in November 2016. There was no specific injury to the right knee. Both knees caused the applicant to limp and he described swelling and clicking in both knees. The left knee occasionally locked. Both knees gave way. Dr Liu referred the applicant for physiotherapy to work on strengthening, flexibility and core stability.

Chronic knee pain was noted in the applicant’s general practitioner’s notes on 10 May 2017 and 5 July 2017.
Dr Mednis prepared a report on 20 July 2017, taking a history of the injury to the left knee at Christmas 2015. Dr Mednis noted:
“Since then he has had severe pain in his left knee and this is now causing severe pain in his right knee.”
Dr Mednis recorded that the applicant underwent an arthroscopy in June 2016, however, the surgery did not relieve the applicant of his symptoms. An MRI of the left knee showed severe marrow oedema in the patella. An MRI of the right knee showed similar changes with severe marrow oedema and retro patella cartilage degeneration. Dr Mednis recommended total knee replacements to both knees with the most painful knee, the left, attended to first.
References to chronic knee pain were made in the general practitioner’s clinical notes throughout 2017.
On 4 December 2017 it was noted:
“left knee gave way sunday - cw cartilage ds
right knee aches”
Ongoing knee symptoms continued to be reported on a regular basis throughout 2018 until a right total knee replacement was performed.

Dr Oates

The applicant relies on medicolegal reports prepared by Dr Christopher Oates, dated 20 October 2016, 30 July 2020 and 15 February 2021.
In his first report, Dr Oates took a history of the injury on 28 December 2015 and the subsequent arthroscopy of the left knee performed by Dr Allen on 24 May 2016. Dr Oates noted that the applicant had not had as good a result from the surgery as he had from previous operations to both knees. The applicant still had soreness in the peri-patellar area and swelling at the back of the left knee. There was locking of the patella when going upstairs. It was noted that the applicant’s lower back was getting a bit sore from limping on the left leg. A slight limp on the left leg was noted on examination.
Dr Oates examined both knees and noted bilateral patellofemoral crepitus present with no pain on patella compression on the right knee. There was wasting of the left thigh girth and restricted range of movement in the left knee compared with the right.
In the report of 30 July 2020, Dr Oates took a history of subsequent events including:
“Following the left knee injury, he put increased weight on the right leg because of ongoing left knee pain and in November 2016 he was turning whilst walking and felt a twinge of pain in the medial joint line of the right knee, but there was no swelling, locking or give way. This pain worsened and was located about the peri-patellar region and he noticed the patella would lock up when he went to stand up from a period of sitting or when he was swimming freestyle to maintain fitness.”
The applicant was referred to Dr Mednis but could not get an appointment until July 2017. When the applicant was seen by Dr Mednis, he noted severe marrow oedema of the left patella and indicated that the only effective treatment would be a total knee replacement. Due to similar findings on the MRI scan of the right knee, this joint also needed replacement. A left total knee replacement was scheduled for 10 October 2017 but not performed as the insurer declined liability. The applicant had been placed on a public hospital waiting list for a right total knee replacement which was performed on 12 July 2018. The applicant went on a public hospital waiting list for the left total knee replacement, which was eventually performed on 24 June 2019.

Dr Oates made a diagnosis as follows:
“For the left knee, the diagnosis is soft tissue contusion with bone bruising and aggravation of chondromalacia patellae which was previously asymptomatic prior to the subject injury and also aggravation of variable thickness up to full-thickness articular cartilage defects over the weight-bearing surface of the femur and a medial meniscal tear which is posttraumatic.
There was a consequential soft tissue injury to the right knee from overuse causing progressive worsening of pre-existing degenerative changes of cartilage, noting the right knee had been the subject of previous partial lateral and medial meniscectomy and the left knee had been subject to previous partial lateral meniscectomy on two occasions. The diagnosis is based on the file evidence, history given, and the results of special investigations, particularly MRI scan, and the operative findings as detailed in the evidence.”
Dr Oates made a combined assessment of 33% WPI for the left and right knees.
In his report of 15 February 2021, Dr Oates confirmed the history previously reported. With regard to diagnosis, Dr Oates said:
“Right knee – There was a consequential soft tissue injury from overuse, which produced progressive aggravation of pre-existing degenerative changes in the medial, lateral and patellofemoral compartments of the right knee. There was a previous history of right knee partial lateral and medial meniscectomy and left knee partial lateral meniscectomy on two occasions.”
Dr Oates was asked whether the need for knee replacement surgeries was causally connected to the injury on 28 December 2015 and responded:
“Yes. In the case of the left knee, there was a frank accident/injury which occurred on that date, resulting in bone marrow oedema from direct contusion, and aggravation of the pre-existing degenerative changes which changes had not resulted in any functional incapacity prior to this date. Unfortunately, an extensive arthroscopic chondroplasty was insufficient in controlling symptoms and the state of his knee progressively deteriorated, resulting in the need for the knee replacement.
The right knee replacement was causally connected by way of being a consequential injury to that of the left knee through a prolonged period of increased weight-bearing on the right leg to favour the painful injured left knee.”
Dr Oates was asked to respond to the medicolegal reports of Associate Professor Miniter obtained by the respondent and stated:
“To the contrary, there was clear evidence of a frank work injury to the left knee, which would have been sufficient to initiate aggravation of the underlying degenerative pathology and it is obvious from the clinical progress that there were ongoing problems, indicating continued aggravation of this left knee. I could not see any evidence where the left knee problems ceased at any stage which in turn would indicate that aggravation had ceased.
As well, there was evidence that a secondary injury to the right knee from overuse from increased weightbearing had occurred as a result of prolonged pain in the left knee, and similarly this led to continued aggravation of the right knee degenerative changes.
In the opinion section, A/Prof Miniter does say the diagnosis of the matter is that of brief aggravation of pre-existing osteoarthritic change affecting both knees. It is difficult to know what he regarded as the aggravating factor when he goes on to say that there is no evidence to link work with the bilateral knee conditions.”
With regard to the opinion given by A/Prof Miniter that the applicant simply had degenerative change affecting the knees, Dr Oates stated:
“This seems to disregard the frank injury which occurred to the left knee, setting off the chain of causation and continuing aggravation of degenerative changes previously present in the left knee but which were essentially asymptomatic for practical purposes and not causing any functional limitations.
This has not been the case, either symptomatically or functionally, since this frank injury occurred with the consequential injury affecting the right knee arising as a direct result of the work-related left knee condition.
There is no suggestion on my part that work caused the degenerative changes in the knees, this is clearly the result of constitutional factors and prior injury, however I maintain my belief that the work injury has initiated aggravation of the left knee, which had continued despite the best efforts of surgery and had resulted in consequential aggravation of quite tolerable pre-existing degenerative changes in the right knee as well.”

A/Prof Miniter

The respondent relies on medicolegal reports prepared by orthopaedic surgeon, A/Prof Paul Miniter, dated 28 September 2017, 13 October 2017, 27 April 2020, 13 May 2020 and 29 May 2020.
A/Prof Miniter took a history of the left knee injury and noted that the applicant began to complain of more significant symptoms at the right knee in about March 2016. The applicant had also been booked into have the right knee replaced
A/Prof Miniter noted the history of arthroscopy at the right knee in May 2014 and noted that at that time osteoarthritic change was identified.
A/Prof Miniter gave the opinion:
“The available evidence would suggest that Mr Sheahan has not had a serious work related injury. I could see no evidence of the investigations nor by way of his arthroscopic findings to suggest that he has other than longstanding degenerative change affecting both knees. Indeed, I do not regard him as a candidate for total knee replacement surgery from which I fear he will have a poor outcome. I note the psychiatric history and I note his previous worker's compensation claims. He comes across as a person with limited motivation and it is not likely he will gain the outcome from total knee replacement that he is seeking.”
A/Prof Miniter considered that no further treatment was required.
In a separate report of the same date, A/Prof Miniter commented on surveillance material apparently showing the applicant engaging in boxing training. A/Prof Miniter commented that if the applicant was capable of boxing he was not a candidate for any type of surgical management and it was not conceivable that the right knee had been injured in the manner claimed.
In the report of 13 October 2017, A/Prof Miniter made an assessment of permanent impairment of the left knee and commented:
“I would clarify that the other knee is not related to the knee that was initially injured and that there is no significant evidence of injury to either knee other than in the long standing pathology that is clearly seen in relation to previous treatments.”
In his report of 27 April 2020, A/Prof Miniter noted the progress history of total knee replacements performed on the right in 2018 and on the left in 2019. A/Prof Miniter referred to the applicant’s psychiatric history and gave a diagnosis:
“The diagnosis of the matter is that of brief aggravation of pre-existing osteoarthritic change affecting both knees. There is no evidence of acute injury.”
In the report of 13 May 2020, A/Prof Miniter was asked to make an assessment of whole person impairment. A/Prof Miniter commented:
“I do not draw a causal relationship between his employment and the need to proceed to total knee replacement. Indeed, in a situation such as this, one is puzzled that he has gone ahead with total knee replacement as a number of observers including myself felt that the outcome was likely to be poor as it has.”

Applicant’s submissions

Mr Steiner submitted that the applicant’s left knee injury caused a soft tissue injury to the right knee in the nature of an aggravation of a disease process at that knee. The main contributing factor to the deterioration was the compensable left knee injury.
Mr Steiner noted that the applicant first injured the right knee in 2014 when sprinting on sand. The applicant subsequently underwent arthroscopy performed by Dr Allen. The applicant gained a significant benefit from that surgery and did not require any further treatment to the right knee after about July 2014.
The applicant commenced work for the respondent in about February 2015, around 10 months after the right knee injury and about seven or eight months after the surgery. The applicant was fully fit and participating in his normal activities including running and surfing by this time. The applicant worked without any physical restrictions until the incident in December 2015.
Mr Steiner noted that there was no dispute that the applicant injured his left knee in the incident on 28 December 2015. An MRI performed on 14 March 2016 indicated that the applicant had suffered an extensive complex tear of the meniscus. Dr Allen described the injury as a significant injury to the knee with chondral contusion of the medial femoral condyle, cartilage loss, bruising and damage to the lateral meniscus which was symptomatic.
In a report of 9 June 2016, Dr Allen described a “long haul” recovery following the left knee surgery.
The applicant’s evidence was that he favoured the left knee, walking with a limp. The applicant always led with the right knee and in activities favoured the left knee. Mr Steiner said there was uncontroverted evidence in the clinical notes and the reports of Dr Oates about six months after the left knee arthroscopy that the applicant was limping on the left leg.
About six months after the arthroscopy, Dr Oates noted that the applicant was limping on the left leg. Dr Oates noted the prolonged recovery attributable to the nature of the pathology. The report repaired by Dr Oates took place prior to the incident when the applicant twisted and turned on the right knee causing it to become symptomatic. The applicant twisted and turned performing normal activity and from that time had experienced significant symptoms in the right knee.
The applicant’s general practitioner referred him to Dr Liu and Dr Mednis. The letter of referral to Dr Mednis referred to favouring the left knee.
Mr Steiner submitted that the relationship between the left knee injury and the right knee condition was explained by Dr Oates. There was a soft tissue condition from overuse which produced progressive aggravation of pre-existing degenerative changes in the medial, lateral and patellofemoral compartments of the right knee.

Mr Steiner submitted that the right knee had been asymptomatic for 14 months prior to the work injury. The right knee remained asymptomatic for a period of time after the left knee injury. The deterioration in the functional ability of the right knee was caused by the injury to the left knee. The applicant’s general practitioner, treating orthopaedic surgeon and Dr Oates agreed on causation.
Mr Steiner noted that the respondent relied on the reports of A/Prof Miniter. It was submitted that those reports should not be accepted over the opinions of the applicant’s treating doctors and Dr Oates. The treating doctors saw the applicant over a longer period of time and were in a better place to give an opinion. A/Prof Miniter did not have access to all of the radiological evidence and formed the view that the applicant had limited motivation. A/Prof Miniter was not qualified to give an opinion as to the applicant’s motivation. The treating evidence indicated that the applicant was a motivated and disciplined sportsman who returned to running, surfing and other activities following his previous injuries. A/Prof Miniter’s perception that the applicant had limited motivation suggested a serious bias that undermined his report.
Mr Steiner submitted that there was no evidence of any malingering or exaggeration. Surveillance material referred to by A/Prof Miniter had not been served and in accordance with r 33 of the Personal Injury Commission Rules 2021 should not be provided to the Medical Assessor.
Mr Steiner submitted that the Commission would prefer the opinions of Dr Mednis, Dr Allen and Dr Oates. Dr Oates reviewed the reports of A/Prof Miniter and identified areas of disagreement. The applicant had ongoing problems and continued aggravation of the left knee. The Commission would not accept that the left knee problem ceased at any time. The treating material provided evidence of frequent attendances upon the applicant’s doctors and complaints of symptoms.
Contrary to A/Prof Miniter’s view that there was no secondary condition, Dr Oates found evidence that increased weight bearing due to the left knee injury had aggravated degenerative changes in the right knee. This took place over a long period of time. Dr Oates and Dr Mednis agreed that there was no alternative to the total knee replacements.
A/Prof Miniter was alone in saying that a total knee replacement was not needed because of a lack of causal relationship to employment.

Respondent’s submissions

Noting that the only claim before the Commission was a claim for lump sum compensation, Mr Harris submitted that only issue was whether the undisputed injury to left knee resulted in the subsequent condition in the right knee. The relevant causal test was that set out in Kooragang Cement Pty Ltd v Bates[1].
[1] (1994) 10 NSWCCR 796 at [810].
Leaving aside A/Prof Miniter’s opinions, the applicant’s evidence disclosed no basis on which to find that the right knee condition resulted from the left knee injury. There was no evidence of symptoms or complaints in the right knee for some 11 months following the left knee injury. There was also evidence of a specific incident involving twisting and turning causing a sudden onset of symptoms, which was unrelated to the work injury to the left knee.
The applicant’s statement gave no suggestion of any symptoms at the right knee prior to the specific episode in November 2016. The applicant described a “significant incident” causing injury to the right knee.
Mr Harris noted the report of Dr Liu indicating that the applicant had aggravated his right knee in November 2016. The history given to Dr Liu of no specific injury to the right knee was contrary to the applicant’s statement evidence and the history recorded by Dr Oates.
The referral to Dr Mednis by Dr Mitchell contained the first contemporaneous evidence of right knee symptoms after the work injury. Dr Mitchell did not make a connection between the symptoms in the right knee and the left knee injury. Mr Harris described this as a significant omission.

Mr Harris acknowledged that Dr Mednis gave the opinion that the severe pain in the right knee was caused by the left knee injury but noted that Dr Mednis gave no further explanation for his opinion. The single report from Dr Mednis in July 2017 did not support the claim being made in respect of the right knee. The only evidence provided from the applicant’s treating surgeon was the sole report in 2017, which was silent on the causation issue in these proceedings.
Dr Oates diagnosed a consequential soft tissue condition due to overuse. Dr Oates’ opinion was, however, inconsistent with the significant twisting incident in November 2016. Dr Oates’ opinion was inconsistent with the absence of symptoms in the right knee prior to that incident. There was no gradual progressive worsening of symptoms. Rather, the evidence suggested a specific onset of right knee symptoms as a result of a significant incident.
Mr Harris submitted that the treating medical evidence suggested that symptoms in the left knee had improved. Following the arthroscopy, Dr Allen gave a generally favourable prognosis and effectively gave the applicant the “all clear” with no further arrangements made to see the applicant.
Mr Harris noted that two sets of clinical records from Kennedy Drive Medical Centre had been provided by the applicant. One set ceased before the twisting incident in November 2016 and the other set commenced well after that incident. The gap in the general practitioner’s notes over the period in which the twisting injury occurred was noted to be significant.
The evidence of the applicant with regard to a significant twisting incident and the reports of the doctors who referred to that incident weighed against the proposition that the condition in the right knee resulted from the injury to the left knee. Applying the common sense test, there should be an award in favour of the respondent in respect of the right knee in a referral of only the left knee injury to a Medical Assessor.

Applicant’s submissions in reply

Mr Steiner referred to the evidence from Dr Allen that lateral compartment damage takes much longer than a medial meniscal tear to recover after arthroscopy. Dr Allen noted extensive damage in the articular cartilage and recommended a gradual return to work. This evidence was consistent with ongoing difficulties at the left knee.

Mr Steiner noted that Dr Liu unequivocally took a history of the right knee being aggravated as a result of favouring the left knee. The reference to no specific incident should be understood to refer to the absence of a significant event such as to the injurious event with the street sweeper.
The letter of referral from Dr Mitchell to Dr Mednis noted the applicant had been favouring his left knee and experiencing right knee pain in the last month. This was consistent with the applicant’s claim of a consequential right knee condition.
Although the respondent submitted that only the particular incident in November 2016 caused symptoms, all of the doctors other than A/Prof Miniter had given an opinion that the progression of disease in the right knee was attributable to the applicant favouring the left knee.
Mr Steiner submitted that the Commission would make an award in favour of the applicant in respect of the right knee condition and refer both knees to the Medical Assessor.

FINDINGS AND REASONS

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.”

It has been accepted that the applicant sustained an injury to his left knee in the event on 28 December 2015. What requires determination in these proceedings is whether the applicant has sustained a consequential right knee condition as a result of that injury.

It is not necessary for the applicant to establish that the right knee condition is itself an ‘injury’ pursuant to s 4 of the 1987 Act. Deputy President Roche in Moon v Conmah[2] observed at [45]-[46]:

“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.”

[2] [2009] NSWWCCPD 134.

In Bouchmouni v Bakhos Matta t/as Western Red Services[3], Deputy President Roche 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’.”
[3] [2013] NSWWCCPD 4.

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[4], 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.”
[4] (1994) 10 NSWCCR 796 at [810].

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.”
It is the applicant who bears the onus of establishing on the balance of probabilities that a condition at the right knee has resulted from the left knee injury. 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 [1 injury to the applicant’s right ankle and her cervical spine. 940] HCA 20; (1940) 63 CLR 691 at 712.”

Whilst the reports of A/Prof Miniter were not ultimately relied upon in the respondent’s submissions at the arbitration hearing, there is some difference in the medicolegal opinions as to the nature and ongoing effects of the left knee injury.
A/Prof Miniter’s early reports indicate that he took the view that the applicant had not had a serious work injury to the left knee. A/Prof Miniter considered that the applicant had
long-standing degenerative changes affecting both knees. In his more recent reports,
A/Prof Miniter appeared to accept that the injurious event would have caused a brief aggravation of pre-existing osteoarthritic change affecting both knees but found no evidence of an acute injury.
There is no doubt on the treating medical evidence and lay evidence before me that there was a substantial history of prior injury and complaints of symptoms at both knees. The applicant had undergone surgery to both knees prior to the injurious event on 28 December 2015.
The contemporaneous evidence does, however, indicate that the applicant sustained a significant, acute injury to the left knee in that event. When Dr Allen saw the applicant on 14 March 2016, he noted the mechanism of injury and the presence of a graze on the superolateral aspect of the left knee, where it was struck in the event. The applicant reported new symptoms, including swelling and pain, interfering with the applicant’s activities of daily living and making it uncomfortable for him to get around.
After reviewing further MRI investigations, Dr Allen concluded that the applicant had sustained a significant injury to the knee involving a chondral contusion over the medial femoral condyle with evidence of cartilage loss in that area. There was associated bruising, further damage in the lateral compartment and maceration of the lateral meniscus which was frayed, unstable and symptomatic. The symptoms were of sufficient severity to warrant an arthroscopy of the left knee, which was performed in May 2016.
Whilst Dr Allen’s reports demonstrate improvements following the arthroscopy, his reports do not indicate a quick or uneventful recovery. Three weeks after the surgery, the applicant was noted to be still limping and feeling his knee lock at times. By July 2016, the applicant’s knee had settled down quite significantly, there was excellent range of motion and no effusion.
Dr Allen did, however, describe the recovery as a “long haul” consistent with the lateral compartment damage. Dr Allen described the presence of extensive damage in the articular cartilage and recommended that the applicant engage in a gradual return to work rather than abruptly beginning heavy manual work. I am not satisfied, therefore, that this report gave the applicant the “all clear” or should be read as indicating that the knee injury had resolved completely.
That the knee remained symptomatic is consistent with the clinical notes recorded by the applicant’s general practitioners, referring to swelling and pain at the left knee in August and September 2016. The letter of referral to Dr Mednis from Dr Mitchell in December 2016 indicated that, since the event at work on 28 December 2015, the applicant had been favouring his left knee.
Contrary to A/Prof Miniter’s opinion, the treating medical evidence records that in the 12 months following the injurious event, the applicant was troubled by significant symptoms in the left knee including swelling and pain, which affected the applicant’s ability to get around and engage in his activities of daily living. The applicant was noted to be limping and favouring the left knee both before and after the surgery in May 2016.
Consistently with the treating medical evidence, in his first report dated 20 October 2016,
Dr Oates also recorded that the applicant had not had as a good result from the arthroscopy performed by Dr Allen in May 2016 as from his other knee surgeries. The applicant still had soreness in the peripatellar area, swelling, and locking of the patella. The applicant limped on the left leg. A slight limp was observed by Dr Oates at that examination.
The lay and medical evidence indicates that symptoms in the right knee were first noted shortly afterwards in November 2016. Dr Mitchell’s letter of referral dated 21 December 2016 referred to right knee pain occurring in the last month. Whilst I accept that Dr Mitchell gave no express opinion on causation of the right knee symptoms, he did refer to those symptoms in the same sentence in which he described the applicant favouring the left knee since the work injury.
The applicant’s own evidence is that he favoured his left knee and walked with a limp, trying to avoid putting weight on his left knee since the incident on 28 December 2015. The applicant felt this was putting a lot of weight and pressure on his right knee. The applicant recalled turning and twisting one day in November 2016 and feeling a “little twinge” in the right knee. The applicant said his right knee had been symptomatic ever since and was now causing significant discomfort.
Although the oral submissions on both sides referred to this incident as “significant”, the applicant’s own evidence does not suggest a significant or severe onset of symptoms in this particular event. Rather, he has described feeling “a little twinge”. Rather than an acute injury, the applicant appears to have been describing the moment he first noticed the symptoms in the right knee in the context of having put a lot of weight and pressure on the right knee, including applying more pressure on the right knee when walking upstairs and rising from a seated position. The applicant’s evidence suggests the symptoms later progressed from the little twinge to significant discomfort by February 2017.
This view of the applicant’s evidence is consistent with the history recorded by Dr Liu when he saw the applicant in February 2017. Dr Liu described ongoing pain in the left and right knees due to patellofemoral overload. Dr Liu recorded that the pain in the left knee never settled and had progressively worsened following the surgery performed by Dr Allen. As a result of favouring the left knee, the right knee was aggravated without a specific “injury” to the right knee.
Dr Mednis saw the applicant in July 2017 and also attributed the severe pain in the applicant’s right knee to the severe pain in the applicant’s left knee as a result of the injury. Dr Mednis noted that the surgery performed by Dr Allen did not relieve the applicant of the symptoms in his left knee. Whilst I accept that this opinion from Dr Mednis does not constitute a detailed and reasoned opinion on causation, it is at least consistent with the opinion given by Dr Oates and the other treating medical evidence.
The history taken by Dr Oates in his report of 30 July 2020 was consistent with the applicant’s evidence and the history revealed by the treating medical evidence. Dr Oates recorded that following the left knee injury, the applicant put increased weight on the right leg because of ongoing knee pain and, in November 2016, was turning whilst walking and felt a “twinge” of pain in the medial joint line of the right knee. Dr Oates noted that there was no swelling, locking or giving way. The pain subsequently worsened and was located about the peripatellar region.
On the background of this history, Dr Oates made a diagnosis of a consequential soft tissue injury to the right knee due to overuse, which had caused progressive worsening of pre-existing degenerative changes in the medial, lateral and patellofemoral compartments.
In giving this opinion, Dr Oates was clearly aware of the previous injury to the right knee and noted the previous partial lateral and medial meniscectomy performed by Dr Allen in 2014.
In his final report, Dr Oates expressly disagreed with the medicolegal opinions of A/Prof Miniter, noting that the frank injury to the left knee set off a chain of causation and continuing aggravation of the degenerative changes previously present in the left knee but which had been asymptomatic for practical purposes and not causing any functional limitations. That aggravation had continued despite the best efforts of surgery and had resulted in consequential aggravation of previously quite tolerable pre-existing degenerative changes in the right knee.
On my review of the evidence, the applicant has demonstrated that his left knee remained significantly symptomatic following the work injury on 28 December 2015. Despite some improvement following the arthroscopy in May 2016, the symptoms persisted. Consistently with his own evidence, the applicant was noted by his treating doctors and Dr Oates at his first examination to have been limping and favouring the left knee. A clear and reasoned opinion, which is consistent with the applicant’s evidence and the treating medical evidence before me, has been given by Dr Oates that the symptoms in the left knee caused increased weight-bearing and overuse in the right knee, causing an aggravation of the pre-existing degenerative changes in that knee.
Dr Oates was clearly aware of the “twinge” noted by the applicant in November 2016 but has not characterised this as a discrete injury responsible in itself for the onset of symptoms.
Dr Oates’s approach to the onset of symptoms in November 2016 is consistent with that recorded by Dr Mitchell, Dr Liu and Dr Mednis. I am not satisfied, in all the circumstances, that the respondent’s characterisation of the onset of symptoms in November 2016 as a significant, discrete event causing an onset of symptoms unrelated to the work injury to the left knee is apt. This characterisation is not supported by any treating or medicolegal evidence before me.
I have given careful consideration to the unusual presentation of the clinical records of Kennedy Drive Medical Centre. It is remarkable that neither set of clinical records covers the period in November 2016 when the symptoms in the right knee were noted to have commenced. No explanation has been provided by the applicant to account for this. Equally, however, the respondent has not identified any attempt it has made to obtain a complete record of the clinical notes.
Having regard to the evidence as a whole, I am satisfied on the balance of probabilities that the left knee injury has resulted in an increase in symptoms and restrictions, ultimately leading to the need for a total knee replacement, at the right knee.
The reports of A/Prof Miniter do not persuade me otherwise. A/Prof Miniter has provided opinions, which do not accord with the body of treating medical evidence and lay evidence before me.
I am satisfied that the applicant has sustained a consequential condition at the right knee as a result of the injury to the left knee on 28 December 2015.
Having made this finding, it is appropriate that the matter be remitted to the President for referral to a Medical Assessor to assess the degree of permanent impairment at the left lower extremity (knee) and right lower extremity (knee) resulting from the injury on 28 December 2015.
The materials to be referred to the Medical Assessor should include all of the evidence admitted in these proceedings.

[2021] NSWPIC 421

20 October 2021