A brief statement is attached setting out the Commission's reasons for the determination.

1. Mabel Urrutia-Garate (the applicant) was employed by The Trustee for Jake Child Care Services Trust t/as Katie's Kindergarten & Early Learning Centre (the respondent) on 6 July 2021 when, in the course of her employment, she sustained a frank injury to her left knee and aggravated a pre-existing degenerative condition of her left knee (together referred to as "the accepted injury").
2. The respondent's insurer (the insurer) accepted liability for the accepted injury, with a date of injury of 6 July 2021.
3. The applicant has now claimed medical expenses pursuant to s 60 of the Workers Compensation Act 1987 (the 1987 Act), including costs of and incidental to left knee arthroscopy, high tibial osteotomy and allograft and plate fixation recommended by

Dr Mustafa Alttahir in his report dated 26 May 2025 and by Dr Gavin Soo in his report dated 7 July 2025 (the surgery). 4. The insurer disputed liability for the surgery on the grounds that: it claimed that the applicant had recovered from the effects of the accepted injury and, further, it disputed that the surgery was reasonably necessary as a result of the accepted injury as required by s 60 of the 1987 Act.

PROCEDURE BEFORE THE PERSONAL INJURY COMMISSION

1. The applicant initiated the present proceedings in the Personal Injury Commission (Commission) by Application to Resolve a Dispute (ARD) lodged on 28 July 2025.
2. The respondent lodged a Reply to ARD (Reply) on 20 August 2025.
3. At a conciliation/arbitration hearing (the hearing), conducted by MS Teams on

7 October 2025, Mr John Gaitanis, counsel, appeared for the applicant, instructed by Walker Law Group. Mr Bill Loukas, counsel, appeared for the respondent, instructed by Lee Legal Group. 4. 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.

1. The parties agreed that the following issues remain in dispute:

(a) whether the applicant recovered from the effects of the accepted injury to the applicant's left knee on 6 July 2021, and

(b) whether the surgery is reasonably necessary treatment as a result of the accepted injury to the applicant's left knee on 6 July 2021, pursuant to s 60 of the 1987 Act.

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

(a) Application to Resolve a Dispute and attached documents;

(b) Reply to Application to Resolve a Dispute and attached documents, and

(c) Application to Admit Late documents which was dated and lodged by the respondent in the Commission on 1 October 2025, and admitted into evidence by consent.

1. No application for leave to cross-examine was made and no oral evidence was given.

1. Both counsel provided comprehensive oral submissions which were recorded and have been considered in full.
2. In summary, behalf of the applicant, Mr Gaitanis:

(a) noted that the respondent now concedes that the accepted injury involved both a frank injury to the applicant's left knee and an aggravation of a pre-existing degenerative condition of her left knee;

(b) noted that the evidence indicates that the applicant has ongoing pain and symptoms which have not been provided any enduring relief by the treatment undertaken to date, including arthroscopic procedures;

(c) submitted that the evidence of the applicant's treating surgeon, Dr Mustafa Alttahir, is persuasive and should be accepted because Dr Alttahir provided a comprehensive explanation of why there was no improvement in the applicant's condition and why the surgery is reasonably necessary to treat the accepted injury. Dr Alttahir specifically addressed the underlying biomechanical cause of the applicant's symptoms, namely varus malalignment leading to medial compartment overload;

(d) submitted that the evidence of independent medical expert qualified by the respondent, Dr Wallace, did not explain why the applicant's symptoms continued and worsened and that his opinion that the accepted injury had now resolved should not be accepted;

(e) submitted that the respondent bears the onus to prove that the effects of the aggravation of the pre-existing degenerative condition had ceased (Elliot v Franklins Pty Ltd [2022] NSWPICPD 38 at [130] - [133]) and the respondent has not discharged that onus, and

(f) the Commission should enter an award for the applicant.

1. In summary, behalf of the respondent, Mr Loukas:

(a) submitted that the Dr Wallace's opinion has a sound basis, is compelling and should be preferred and accepted;

(b) submitted that the evidence demonstrates that the applicant has undergone various treatment to treat the accepted injury, which includes a meniscal repair, so that the applicant no longer suffers from that condition;

(c) submitted that the medical evidence shows that the applicant had two

pre-existing conditions involving the left knee, being a varus deformity and an osteoarthritic condition;

(d) submitted that it is significant that approximately two weeks prior to the applicant sustaining the accepted injury, the applicant complained of pain in his left knee, however subsequent doctors were not aware of that pre-existing history. In particular, Dr Soo recorded that the applicant denied any pre-existing pain and injury to the left knee;

(e) submitted that the Dr Alttahir's evidence that the accepted injury initiated a cascade of symptoms miscarried because it does not give due consideration to the fact that the left knee symptoms were already initiated prior to the accepted injury, and the accepted injury involved a tear of the meniscus, which was subsequently repaired. It is also significant that the applicant reported bilateral knee symptoms, although the recommendation was to initially operate on the left knee only;

(f) the surgery involves a cutting of the bones to realign the tibia, which is a

bio-mechanical issue involving the applicant's pre-existing bio-mechanical bone issue and is not addressing the meniscal tear that was part of the accepted injury;

(g) submitted that a proper analysis of the evidence should give rise to a determination that the symptoms and effects of the accepted injury resolved and that the applicant's current left knee symptoms are due to the pre-existing left knee degenerative condition and pathology;

(h) submitted that the evidence of independent medical expert qualified by the respondent, Dr Wallace, should be preferred and accepted, and

(i) submitted that the Commission should find that the symptoms and effects of the accepted injury have resolved and that the surgery is not reasonably necessary as a result of the accepted injury.

(a) submitted that the respondent's argument has not been dealt with by Dr Wallace and does not hold up;

(b) submitted that it is irrelevant whether the applicant's left knee condition was symptomatic or non-symptomatic because the accepted injury did not just involve a medial meniscus tear;

(c) submitted that Dr Wallace provided no explanation of symptoms in the applicant's bilateral knees aggravated by the accepted injury;

(d) submitted that the Commission needs to be cautious about evidence provided by clinical records, however the applicant did tell Dr Wallace that her work aggravated her knee condition, and

(e) submitted that it is only necessary for the applicant to demonstrate that the injury was a material contribution to the need for the treatment, and it does not need to be the only cause.

1. Section 60 of the 1987 Act relevantly provides:

"60 Compensation for cost of medical or hospital treatment and rehabilitation etc

(1) If, as a result of an injury received by a worker, it is reasonably necessary that:

(a) any medical or related treatment (other than domestic assistance) be given, or

(b) any hospital treatment be given, or

(c) any ambulance service be provided, or

(d) any workplace rehabilitation service be provided,

the worker's employer is liable to pay, in addition to any other compensation under this Act, the cost of that treatment or service and the related travel expenses specified in subsection (2)."

1. Burke CCJ in Rose v Health Commission (NSW),[1] (Rose) stated:

"...Treatment is necessarily purposive. Treatment, in the medical or therapeutic context, relates to the management of disease, illness or injury by the provision of medication, surgery or other medical service designed to arrest or abate the progress of the condition or to alleviate, cure or remedy the condition. It is the provision of such services for the purpose of limiting the deleterious effects of a condition and restoring health. If the particular 'treatment' cannot, in reason, be found to have that purpose or be competent to achieve that purpose, then it is certainly not reasonable treatment of the condition and is really not treatment at all. In that sense, an employer can only be liable for the cost of reasonable treatment..." (my emphasis)

1. In Diab v NRMA Ltd,[2] Roche DP, referring to the decision in Rose[3] set out the test for determining if medical treatment is reasonably necessary as a result of a work injury_:_

"The standard test adopted in determining if medical treatment is reasonably necessary as a result of a work injury is that stated by Burke CCJ in Rose v Health Commission (NSW) [1986] NSWCC2; [1986] NSWCC 2; (1986) 2 NSWCCR 32 (Rose) where his Honour said, at

1. Any necessity for relevant treatment results from the injury where its purpose and potential effect is to alleviate the consequences of injury.
2. It is reasonably necessary that such treatment be afforded a worker if this Court concludes, exercising prudence, sound judgment and good sense, that it is so. That involves the Court in deciding, on the facts as it finds them, that the particular treatment is essential to, should be afforded to, and should not be forborne by, the worker.
3. In so deciding, the Court will have regard to medical opinion as to the relevance and appropriateness of the particular treatment, any available alternative treatment, the cost factor, the actual or potential effectiveness of the treatment and tis place in the usual medical armoury of treatments for the particular condition."
4. Roche DP also noted that the Commission has generally referred to and applied the decision of Burke CCJ in Bartolo v Western Sydney Area Health Service:[4]

"The question is should the patient have this treatment or not. If it is better that he have it, then it is necessary and should not be forborne. If in reason it should be said that the patient should not do without this treatment, then it satisfies the test of being reasonably necessary."

"In the context of s 60 the relevant matters, according to the criteria of reasonableness, include, but are not necessarily limited to, the matters noted by Burke CCJ at point (5) in Rose (see [76] above), namely:

• the appropriateness of the particular treatment;
• the availability of alternative treatment, and its potential effectiveness;
• the cost of the treatment;
• the actual or potential effectiveness of the treatment, and
• the acceptance by medical experts of the treatment as being appropriate and likely to be effective.

With respect to point (d), it should be noted that while the effectiveness of the treatment is relevant to whether the treatment was reasonably necessary, it is certainly not determinative. The evidence may show that the same outcome could be achieved by a different treatment, but at a much lower cost. Similarly, bearing in mind that all treatment, especially surgery, carries a risk of a less than ideal result, a poor outcome does not necessarily mean that the treatment was not reasonably necessary. As always, each case will depend on its facts."

1. A commonsense evaluation of the causal chain is required. In Kooragang Cement Pty Ltd v Bates,[5] Kirby P (as his Honour then was) stated:

"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 now not 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."[6]

1. In Murphy v Allity Management Services Pty Ltd[7] Roche DP stated:

"... 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 Pty Ltd (1979) 53 WCR 167; ACQ Pty Ltd [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.

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)."

1. In Elliot v Franklins Pty Ltd [2022] NSWPICPD 38 at [130] - [133], Phillips P held that the evidentiary onus to prove that an aggravation has ceased, rests with the party who makes the assertion: Commonwealth v Muratore [1978] HCA 47; 141 CLR 296 and University of New South Wales v Brooks [2014] NSWWCCPD 68 applied.

The appropriateness of the particular treatment

1. The applicant gave evidence by way of a written statement. The applicant described having severe and constant ongoing left knee pain, functional limitations and consequential conditions following the accepted injury despite various conservative treatment and surgeries.
2. Various treating medical evidence is generally consistent with the applicant's evidence, and indicates the following history of events, which I accept:

(a) on 30 June 2021, the applicant consulted her treating general practitioner, Dr Nisha Ajimal, and reported a two week history of left-sided knee pain, with no history or injury nor trauma to the joint, she was treated conservatively and an

X-ray left knee was requested;

(b) the applicant was treated conservatively with physiotherapy and anti-inflammatory medication;

(c) on 7 July 2021, and X-ray Left Knee was reported to show: no fracture nor dislocation; mild reduction of joint space in the medial compartment suggestive of mild osteoarthritis; and joint space in the lateral compartment and patellofemoral compartment is preserved;

(d) on 7 July 2021, the applicant consulted Dr Ajimal who advised that imaging showed evidence of mild osteoarthritis in the medial compartment and recommended conservative treatment;

(e) on 15 July 2021, the applicant consulted Dr Ajimal regarding worsening knee pain and discussed treatment options;

(f) on 16 July 2021, the applicant consulted Dr Shilpi Shrivastav, general practitioner, who reported that the applicant injured her left knee in an injury at work on 6 July 2021 and had worsened pain, in the context of a history of pain in her left knee for the previous four weeks;

(g) the applicant continued to be treated conservatively with physiotherapy and anti-inflammatory medication;

(h) on 15 November 2021, the applicant consulted Dr Ajimal and reported a recent recurrence of her left-sided knee pain;

(i) the applicant was referred for a specialist review with Dr Vera Kinzel, orthopaedic surgeon, who initially assessed the applicant on or about 18 November 2021, queried the possibility of an underlying meniscal tear and requested an MRI scan of the left knee;

(j) an MRI Left Knee on or about 23 November 2021, was reported to show a large posterior horn tear;

(k) on 3 December 2021, the applicant attended Dr Nisha Ajimal who stated that the MRI Scan revealed a large posterior horn tear which would require an arthroscopy and meniscal debridement;

(l) in a report dated 20 January 2022, Dr Vera Kinzel, orthopaedic surgeon, reported that recent MRI scan showed an MCL combined with a large underlying medial meniscal tear, and that the applicant would require a left knee arthroscopy and meniscal debridement. Dr Kinzel expressed the opinion that the applicant's employment was the sole contributing factor to the applicant's symptoms;

(m) on 18 February 2022 (or 22 February 2022), the applicant underwent left knee arthroscopic debridement with partial medial meniscectomy and medial compartment chondroplasty, performed by Dr Vera Kinzel;

(n) in the post-operative period, the applicant continued with a course of physiotherapy and anti-inflammatory medication and she also underwent a corticosteroid injection at the joint about three months post-operatively;

(o) on 23 June 2022, Dr Vera Kinzel, orthopaedic surgeon, reported that the applicant said that, whilst her overall knee pain had improved, she got sharp pain episodes over the medial joint line when she performed twisting motions. Dr Kinzel expressed the opinion that it is indicative of something getting caught in the joint line and that a further arthroscopy and meniscal debridement would be appropriate;

(p) on 29 July 2022, Dr Vera Kinzel, orthopaedic surgeon, reported that following the left knee arthroscopy and meniscal debridement, the applicant continued to complain of pain of the medial aspect and that recent imaging suggested that the applicant had a further tear affecting her medial meniscus for which she required a second arthroscopy and meniscal debridement. Dr Kinzel stated that the applicant's employment was the sole contributing factor to her situation;

(q) on 21 September 2022, Dr Fred Nouh, orthopaedic surgeon, reported that the applicant was still symptomatic from the meniscal tear, with pain in the medial compartment, and that he recommended that the applicant undergo a repeat arthroscopy on her left knee to remove any residual meniscal tear;

(r) the applicant was later referred for a second opinion with Associate Professor John Ireland, orthopaedic surgeon, who initially assessed the applicant on

2 November 2023. Associate Professor Ireland reported that the MRI from May 2022 showed that there was a persistent and substantial flap tear of the postural behind the medial meniscus and some early degenerative changes. Associate Professor Ireland recommended that the applicant undergo revision surgery, being an arthroscopy and medial meniscectomy. Associate Professor Ireland stated that, because the applicant had some early degenerative changes, the surgery may not completely eliminate her pain but noting that the applicant was presently markedly restricted by pain;

(s) on 15 March 2024 the applicant underwent revision left knee arthroscopic meniscal debridement with chondroplasty and partial medial meniscectomy, performed by Associate Professor John Ireland, who reported operative findings that the applicant had a complex tear of the posterior horn or the medial meniscus, some patches of grade IV (chondral loss) at the medial femoral condyle and grade III changes (chondral loss) in the retropatellar surface;

(t) on 12 September 2024, Associate Professor John Ireland reported that the applicant was progressing well, with a substantial reduction in pain, she was walking without any significant limp and had an excellent range of motion;

(u) on 19 December 2024, Dr Morgan Mo, general practitioner reported that the applicant continued to experience suffered chronic pain and incapacity of the left knee and consequential conditions;

(v) on 23 December 2024, an MRI Left Knee (performed on 19 December 2024) was reported to show:

"Horizontal undersurface linear signal hyperintensity of the medial meniscus posterior horn partially extending into the posterior root and into the posterior body 20 mm in length. No displaced flap fragment or parameniscal cyst. Meniscocapsular oedema along the posterior body horn junction without discrete cyst formation. The medial collateral complex is intact. Region of irregular grade III chondromalacia involving the central aspect of the medial femoral condyle in addition to several full-thickness penetrating fissures and subchondral marrow oedema. Tibial articular cartilage is thinned and there is a small focus of subchondral oedema anteriorly.

The anterior cruciate and posterior cruciate ligaments are intact.

The lateral meniscus, lateral collateral ligament complex and posterolateral corner structures are intact and normal in appearance. Lateral compartment articular cartilage is preserved.

Normal patellofemoral congruence. Full-thickness chondral fissure along the superior aspect of the median patellar ridge with underlying reactive subchondral marrow oedema. Articular cartilage is otherwise preserved. Bony enthesopathic change at the quadriceps insertion. Small joint effusion. No popliteal fossa abnormality.

1. Persistent conversion signal at site of previously repaired medial meniscus horizontal undersurface tear, no displaced flap fragment or parameniscal cyst.
2. Region of grade 3-4 chondromalacia within the central aspect of the MFC with underlying reactive marrow oedema as a potential source of acute symptoms although correlation would be required with preoperative imaging.
3. Focal full-thickness chondral erosion along the median patellar ridge.";

(w) in the post-operative period, the applicant continued with a course of physiotherapy which ceased In January 2025;

(x) on or about 9 January 2025, an MRI Lumbar Spine showed mild multilevel spondylosis, right L4-5 subarticular recess stenosis with potential L5 nerve root compression;

(y) on 20 January 2025, Dr Eric Lim, general practitioner, reported that the applicant suffered chronic pain, dysfunction and incapacity of the left knee and consequential conditions;

(z) on 12 February 2025, Dr Maylyn Goh, general practitioner, recorded that the applicant reported persistent left knee pain;

(aa) on 28 January 2025, Dr Mustafa Alttahir, orthopaedic surgeon, reviewed the applicant and discussed surgical treatment options including left high tibia osteotomy. In his report dated 28 January 2025, Dr Alttahir reported:

I had a lengthy discussion with Mabel regarding her history, examination findings, and reviewed her imaging. I explained that her previous arthroscopic surgeries have not addressed the underlying biomechanical issues contributing to her pain and that repeating a similar procedure is unlikely to be beneficial. I explained that her varus malalignment is causing medial compartment overload, leading to her meniscal tear and chondral damage.

I discussed three surgical options: a high tibial osteotomy (HTO), a unicompartmental knee replacement (UKR), and a total knee replacement (TKR). I explained that while a TKR would likely provide pain relief, it would result in an artificial joint, and I believe she is too young and active to consider this option at this stage. I explained that a UKR would provide faster recovery but would still involve replacing part of her joint with an artificial component.

I explained that my preferred option would be an HTO, which would involve realigning her leg to offload the medial compartment and potentially delay or prevent the need for a knee replacement in the future. I explained that this procedure involves cutting the bone, wedging it open, and fixing it in a corrected position with a plate and screws. I showed her examples of previous patients who had undergone this procedure and explained the recovery process, which involves 6 weeks of non-weight-bearing on crutches, followed by 6 weeks of partial weight-bearing, with full recovery taking 6-12 months.

I also explained the risks and complications associated with each procedure, including infection, wound healing problems, nerve or blood vessel injury, fracture, compartment syndrome, malunion or non-union, undercorrection or overcorrection, CRPS, DVT/PE, incomplete pain relief, hardware prominence, and the need for revision surgery.

I emphasised that I do not want to pressure her into any decision and that she should take time to consider her options.

I will see her again in three weeks to review the scans, answer any further questions, and formulate a definitive management plan."

(bb) on 18 February 2025, Dr Mustafa Alttahir prepared a treatment management plan, noting that the applicant continued to experience left medial knee pain. Dr Alttahir reported:

Left knee arthroscopy, high tibial osteotomy and allograft fixation

It was a pleasure seeing Mabel for review. She continues to experience left medial knee pain since our last consultation.

- Right knee ROM -10 to 140 degrees, ligaments intact

- Left knee ROM -5 to 130 degrees, laxity to anterior drawer and Lachman test

- Large transverse scar, left anterior knee, pre-patellar, sustained age 10

- Long leg alignment x-rays reviewed today demonstrate varus alignment of both knees. Left knee medial joint space significantly narrowed compared to lateral joint space, with spur formation. Right knee medial joint space narrowing and spur formation also present, less severe than left.

- Left knee MRI, i-Med, 19/12/24, reported retro patella chondromalacia, with some marbling in the central median ridge of the patella, and bone marrow edema around the medial femoral condyle.

I explained to Mabel that the increased pressure on the medial compartment of her left knee is most likely due to her varus alignment and is contributing to her pain. I discussed the findings of her x-rays and MRI in detail, in particular the narrowing of the medial joint space. I again explained that repeating arthroscopic surgery is unlikely to be beneficial.

I again discussed the surgical options of HTO, UKR and TKR. I explained that my preferred option is a left HTO, which would involve realigning her leg to offload the medial compartment. I explained that this procedure would involve cutting the bone, wedging it open, and fixing it in a corrected position with a plate and screws. I showed her examples of previous patients who have undergone this procedure. I explained the recovery process, which involves 6 weeks NWB on crutches, followed by 6 weeks PWB, with full recovery taking 6-12 months.

I explained the possibility of requiring a knee replacement in future, despite having HTO. I explained that if a knee replacement is required in future, after previously having a HTO, the HTO can be reversed, whereas a knee replacement is not reversible. I explained that the average longevity of HTO is 10-15 years.

I explained the risks of surgery, including infection, wound healing problems, neurovascular injury, fracture, compartment syndrome, malunion/non-union, undercorrection/overcorrection, CRPS, DVT/PE, incomplete pain relief, hardware prominence and need for revision surgery. I specifically mentioned the risk of amputation, whilst emphasising that this is very rare. I also mentioned the likelihood of significant post operative pain, swelling and bruising.

I advised that if she has no pain in her right knee, we will not operate on that side. I explained that if she has an injury in the future, she may require surgery on the right knee."

(cc) Dr Alttahir issued a Treatment Information Form dated 18 February 2025, which stated:

"Diagnosis: Left Knee medial compartment meniscal tear post-workplace injury anddegenerative changes

Recommended Treatment: Left knee arthroscopy, high tibial osteotomy and allograft + plate fixation

Alternative Treatment: Analgesia, NSAIDS, physio/low impact exercise programme

Natural History: Won't get better- increasing pain and deformity

Anaesthetic: General Anaesthetic - death, stroke, heart attack

Surgical: Infection- wound healing problems, DVT/PE, Nerve injury- numbness around wound,

Compartment syndrome, Blood Vessel injury, Stiffness, Instability, Incomplete pain relief

Treatment Goals: relieve pain correct deformity and maintain movement

Time: Weight bearing 20% for 6 weeks; weightbearing as tolerated with 1 crutch for 6 weeks; no crutches after; 6-12 months for full recovery

Please Note: The complications discussed are not an exhaustive list of all possible complications for a given procedure."

(dd) also on 18 February 2025, Dr Alttahir issued a request for approval of the surgery, which included an estimate of his fees, and

(ee) the applicant was also treated by Dr Peter Khong, neurosurgeon for lower back pain and on or about 17 March 2025, the applicant underwent a CT-guided perineural injection at the right L5 nerve root.

1. In a report dated 26 May 2025, Dr Mustafa Alttahir:

(a) stated that the surgery is required because of the accepted injury, noting that the applicant was functionally well and employed full-time prior to the injury, however the accepted injury initiated a cascade of persistent and progressive symptoms;

(b) stated that, following the accepted injury, the applicant underwent two arthroscopic surgeries (in February 2022 and in March 2024), yet her medial compartment knee pain persisted, and imaging and clinical findings support the conclusion that the accepted injury led to a symptomatic medial meniscus tear and subsequently accelerated degeneration in the medial compartment, compounded by the applicant's underlying varus alignment;

(c) stated that the applicant's current condition, being symptomatic medial compartment overload due to varus malalignment with degenerative change, is a direct result of the biomechanical consequences initiated by the accepted injury;

(d) stated that the surgery, being left knee arthroscopy followed by high tibial osteotomy with allograft and plate fixation, is the most appropriate treatment option for the applicant's condition;

(e) stated that the two previous arthroscopies did not address the underlying biomechanical cause of significant varus malalignment, noting that radiological imaging confirms medial joint space narrowing with early osteoarthritis, consistent with the clinical findings of medial compartment overload;

(f) stated that HTO is particularly well-suited for active patients under 75 years of age with isolated medial compartment degeneration and varus alignment, because it preserves the native knee joint, improves function, and has the potential to delay or even avoid the need for knee replacement;

(g) stated that, in contrast, repeating arthroscopy, would not correct the malalignment and has already failed to provide symptom relief;

(h) stated that alternative treatments such as total knee replacement and unicompartmental knee replacement were considered and discussed, however total knee replacement is a more invasive option generally reserved for patients with severe or multi-compartmental arthritis, and would irreversibly replace the applicant's natural joint;

(i) stated that the applicant remains functionally independent and active, making her a less suitable candidate for total knee replacement at this stage.

(j) stated that unicompartmental knee replacement may be a valid alternative, but still involves joint replacement with artificial components;

(k) stated that HTO maintains the native joint and can significantly delay or avoid prosthetic surgery;

(l) stated that non-surgical options including physiotherapy, analgesia, and injections have already been trialled and found to be ineffective;

(m) in relation to the cost of the surgery, stated that from an economic perspective, HTO is a cost-effective solution in the long term, noting that it is generally less costly than a knee replacement when factoring in the potential for HTO to restore function and postpone or prevent the need for future arthroplasty;

(n) stated that, additionally, HTO avoids many of the long-term risks and complications associated with joint replacement, such as revision surgery and prosthesis failure;

(o) in relation to the actual or potential effectiveness of the surgery, stated that the proposed HTO directly addresses the underlying biomechanical cause of the applicant's symptoms, namely, varus malalignment leading to medial compartment overload;

(p) stated that, by realigning the mechanical axis of the leg, the surgery is expected to offload the degenerated compartment, reduce pain, and improve overall function;

(q) stated that, in patients with similar clinical profiles, being varus alignment, isolated medial compartment degeneration, and failed response to conservative and arthroscopic interventions, the surgery has been shown to restore mobility and delay the progression of arthritis;

(r) stated that, based on the applicant's imaging and clinical presentation, the likelihood of achieving meaningful symptom relief and improved function through HTO is high;

(s) stated that, in relation to acceptance by medical experts of the surgery as being appropriate and likely to be effective, that HTO is a well-established and widely endorsed procedure within the orthopaedic community for patients with isolated medial compartment osteoarthritis and varus deformity, and it is routinely performed in specialist centres for patients who are not yet ideal candidates for joint replacement but who have ongoing symptoms that significantly impact their quality of life;

(t) stated that the surgery is supported by clinical guidelines and is commonly offered in comparable cases, especially where conservative and less invasive interventions have failed to provide relief;

(u) stated that, in the applicant's case, the recommendation for HTO aligns with accepted best practice in orthopaedic care;

(v) stated that the accepted injury has not resolved, noting that the applicant continues to suffer from significant medial knee pain, which interferes with her daily function and causes ongoing sleep disturbance;

(w) stated that, on clinical examination, there is clear evidence of varus deformity, anterior laxity, localized tenderness over the medial joint line, and radiographic signs of medial joint space narrowing;

(x) stated that those findings are not indicative of a resolved condition but rather demonstrate persistent and progressive pathology, and

(y) stated that, importantly, the pattern and severity of the applicant's symptoms are not consistent with pre-existing or age-related degeneration alone, and instead, they reflect the biomechanical and structural consequences of the accepted injury, which initiated the deterioration and has led to the applicant's current level of impairment.

1. It is clear from the medical evidence, and not in dispute, that the applicant had a pre-existing degenerative condition involving her left knee and that, some two weeks prior to the accepted injury, the applicant sought medical treatment for left knee symptoms.
2. It is particularly relevant that the accepted injury involves both a frank injury to the applicant's left knee and also an aggravation of the pre-existing degenerative condition of the applicant's left knee.
3. It is also clear from the applicant's evidence and the medical evidence, and I accept, that the applicant has severe and constant ongoing left knee pain and functional limitations following the accepted injury despite various conservative treatment and surgeries.
4. An X-ray left Knee taken on 7 July 2021 indicated mild reduction of joint space in the medial compartment suggestive of mild osteoarthritis, although the joint space in the lateral compartment and patellofemoral compartment was preserved.
5. An MRI left Knee taken on or about 23 November 2021 showed a large posterior horn tear.
6. On or about 18 February 2022, the applicant underwent left knee arthroscopic meniscal debridement with partial medial meniscectomy and medial compartment chondroplasty.
7. On 15 March 2024, the applicant underwent revision left knee arthroscopic meniscal debridement with partial medial meniscectomy and chondroplasty. Operative findings included that the applicant had a complex tear of the posterior horn or the medial meniscus, some patches of grade IV (chondral loss) at the medial femoral condyle and grade III changes (chondral loss) in the retropatellar surface.
8. An MRI left Knee taken on or about 19 December 2024 indicated chondromalacia within the central aspect of the medial femoral condyle, with some full-thickness chondral erosion along the median ridge of the patella, and bone marrow edema around the medial femoral condyle.
9. The applicant's treating orthopaedic surgeon, Dr Mustafa Alttahir diagnosed symptomatic medial compartment overload due to varus malalignment with degenerative change. Dr Alttahir stated that a varus malalignment of both knees is demonstrated by long leg alignment X-rays. Dr Alttahir noted that imaging shows that the left knee medial joint space is significantly narrowed compared to the lateral joint space, with spur formation, and that whilst right knee medial joint space narrowing and spur formation also present, it is less severe than the left.
10. Dr Alttahir opines that the genu varum is causing medial compartment overload, which is compounding meniscal tear and chondral damage of the left knee, and is contributing to the applicant's pain, and that was not addressed by the previous arthroscopic surgeries.
11. Dr Alttahir recommends the surgery, being left knee arthroscopy, high tibial osteotomy and allograft and plate fixation. The surgery would involve cutting the bone, wedging it open, realigning the applicant's leg to offload the medial compartment and fixing it in a corrected position with a plate and screws. The surgery is designed to shift weight-bearing pressure from a damaged part of the knee to a healthy area.
12. Dr Alttahir stated that the surgery directly addresses the underlying biomechanical cause of the applicant's symptoms, namely, varus malalignment leading to medial compartment overload, by realigning the mechanical axis of the leg, which is expected to offload the degenerated compartment, reduce pain, and improve overall function.
13. Dr Alttahir stated that the surgery has been shown to restore mobility and delay the progression of arthritis in patients with similar clinical profiles of varus alignment, isolated medial compartment degeneration, and failed response to conservative and arthroscopic interventions.
14. Dr Alttahir stated that the surgery is particularly well-suited for active patients under 75 years of age with isolated medial compartment degeneration and varus alignment, because it preserves the native knee joint, improves function, and has the potential to delay or even avoid the need for knee replacement.
15. Dr Alttahir opines that, based on the applicant's imaging and clinical presentation, the likelihood of achieving meaningful symptom relief and improved function through HTO is high.
16. Dr Alttahir opines that the surgery will provide the applicant with symptomatic relief and potentially delay or prevent the need for a knee replacement in the future, thus avoiding many of the long-term risks and complications associated with joint replacement, such as revision surgery and prosthesis failure.
17. Dr Alttahir stated that the average longevity of high tibial osteotomy is ten to fifteen years.
18. Dr Alttahir explained that it is possible that, despite having a high tibial osteotomy, the applicant may still require a knee replacement in future and, if that is required, the high tibial osteotomy can be reversed.
19. Dr Alttahir has given evidence that he explained the procedure, recovery process, risks and complications of the surgery to the applicant.
20. The applicant clearly wishes to proceed with the surgery to address her ongoing pain and functional limitations.
21. Considering the applicant's evidence and the treating medical evidence as a whole, I accept that the applicant has ongoing pain and functional limitations involving her left knee and the applicant's treating orthopaedic surgeon considers that the surgery is the most appropriate treatment option to address the applicant's current pathology, symptoms and functional restrictions and that the applicant wishes to proceed with the surgery.

The availability of alternative treatment, and its potential effectiveness

1. Dr Gavin Soo, orthopaedic surgeon, independent medical expert qualified by the applicant, gave evidence that alternative treatment options are total knee replacement surgery or

non-surgical measures such as physiotherapy, pain management, activity modification and other types of injections such as PRP or synovial fluid replacement. 2. Dr Raymond Wallace, orthopaedic surgeon, qualified by the applicant, did not identify any alternative treatment options. 3. Dr Alttahir has given evidence that alternative surgical options are a unicompartmental knee replacement and a total knee replacement. Dr Alttahir opines that while a total knee replacement would likely provide pain relief, it would result in an artificial joint. Dr Alttahir opines that a unicompartmental knee replacement would provide faster recovery, but would still involve replacing part of the applicant's joint with an artificial component. 4. Dr Alttahir opines that the applicant remains functionally independent and active, making her a less suitable candidate for an artificial joint or artificial component at this stage. Dr Alttahir noted that a total knee replacement and a unicompartmental knee replacement is not reversible. 5. Dr Alttahir opines that simply repeating the previous arthroscopic surgery is unlikely to be beneficial because it has not provided any enduring symptom relief to date, and does not address the genu varum which is causing medial compartment overload which is compounding the accepted injury aggravation of the degenerative condition. 6. It is clear from the treating medical evidence, and I accept, that various conservative treatment options have not provided any enduring relief to date. Surgery in the form of a total knee replacement or unicompartment knee replacement would involve irreversible replacement of the knee with artificial components, which is less appropriate given the applicant's relatively young age and level of functional activity.

1. Dr Alttahir's request for approval of the surgery included an estimate of his fees. Dr Alttahir stated that from an economic perspective, the surgery is a cost-effective solution in the long term, noting that it is generally less costly than a knee replacement when factoring in the potential for high tibial osteotomy to restore function and postpone or prevent the need for future arthroplasty.
2. There is no evidence which challenges Dr Alttahir's estimate of costs and the respondent has made no submissions in that regard.

The acceptance by medical experts of the treatment as being appropriate and likely to be effective.

1. The applicant's treating orthopaedic surgeon, Dr Alttahir, gave evidence that high tibial osteotomy is a well-established and widely endorsed procedure within the orthopaedic community for patients with isolated medial compartment osteoarthritis and varus deformity, and it is routinely performed in specialist centres for patients who are not yet ideal candidates for joint replacement but who have ongoing symptoms that significantly impact their quality of life. Dr Alttahir stated that the surgery is supported by clinical guidelines and is commonly offered in comparable cases, especially where conservative and less invasive interventions have failed to provide relief. Dr Alttahir stated that, in the applicant's case, the recommendation for high tibial osteotomy aligns with accepted best practice in orthopaedic care.
2. In a report dated 4 April 2022, Dr Raymond Wallace, orthopaedic surgeon, independent medical expert qualified by the respondent, reported on his examination of the applicant on 30 March 2022. Dr Wallace:

(a) diagnosed a work injury on 6 July 2021, being an acute on chronic medial meniscal tear left knee and also aggravation of pre-existing medial compartment osteoarthritis left knee;

(b) expressed the opinion that the work injury on 6 July 2021 was a substantial contributing factor to her current left knee condition, with a proportion being due to medial compartment osteoarthritis at the left knee;

(c) noting that the applicant was some eight months post-injury and six weeks post-surgery, recommended ongoing conservative treatment with physiotherapy, an exercise program and analgesic medication, and

(d) stated that the applicant has a good prognosis for ongoing recovery and function at her left knee with a conservative treatment regime, and stated that the applicant does not require further surgical intervention.

1. In a report dated 7 April 2025, Dr Raymond Wallace reported on his examination of the applicant on 26 March 2025. Dr Wallace:

(a) diagnosed pre-existing symptomatic degenerative osteoarthritis at the left knee prior to accepted injuries on 6 July 2021, noting that although the applicant had denied any pre-existing injury, she had sought medical treatment and underwent X-rays of her left knee in late June 2021 (being approximately two weeks prior to the accepted injury on 6 July 2021);

(b) expressed the opinion that at the time of the accepted injury, the applicant suffered an acute on chronic medial meniscal tear at the left knee and aggravation of pre-existing symptomatic degenerative osteoarthritis at the joint;

(c) expressed the opinion that the work-related injury to the left knee on 6 July 2021 would have resolved by August 2022 (that is, within six months of the applicant's initial arthroscopy in February 2022) and that the applicant had recovered from the effects of the accepted injury;

(d) noted that the applicant reported a continuing constant aching pain at the medial joint line of her left knee and an onset of lumbar spine pain, which the applicant attributed to alteration in her gait;

(e) opined that the applicant's current left knee symptoms are due to pre-existing symptomatic degenerative osteoarthritis at the left knee which is constitutional in origin and is unrelated to the applicant's employment (noting that the applicant was then aged 61 years);

(f) on that basis, opined that the applicant's employment with the respondent is not a "substantial contributing factor" to any current left knee condition;

(g) stated that there is no medical indication nor justification for the applicant to undergo further surgery and in particular, a left HTO at the left leg and that she would not benefit from any further surgical intervention at her left knee;

(h) expressed the opinion that the applicant does not require any further treatment nor medical review as a result of her work-related left knee injury on 6 July 2021 or condition, which has resolved, and

(i) stated that the surgery "is not reasonable and necessary nor related to any work-related condition at the left knee".

1. In a report dated 7 July 2025, Dr Gavin Soo, orthopaedic surgeon, independent medical expert qualified by the applicant, reported on his examination of the applicant on 7 July 2025. Dr Soo:

(a) diagnosed aggravation of underlying degenerative osteoarthritis to the left knee;

(b) stated that:

"I have read the report by Dr Alttahir dated 28/1/2025. In it he details the reasons for the recommendations for surgery.

Ms Garate, continues to experience pain and dysfunction to her left knee since her original injury back in 2021. She has not been able to return back to her full capacity due to the left knee. She has had 2 operations to the knee, as well as many sessions of physiotherapy and cortisone injections. I have viewed her MRI scan performed in December 2024 which does show arthritic change to the medial compartment with subchondral bone oedema. Her pain is centred primarily to the medial aspect of the knee. Based on the longevity of her symptoms, the lack of improvement with all measures previously (including physiotherapy and cortisone injection), the findings on MRI and he age, I think that the surgery proposed by Dr Alttahir is reasonably necessary. It has been proven in literature to be an effective solution to isolated compartment osteoarthritis.

The alternative options are ongoing non-surgical measures such as physiotherapy, pain management and other types of injections such as PRP or synovial fluid replacement. The other surgical option would be a total knee replacement.";

(c) noted that the applicant still clinically has pain and dysfunction to the knee in the same area that was originally injured;

(d) on that basis, opined that the accepted injury had not resolved;

(e) stated that, for osteoarthritis to the knee, a high tibial osteotomy or arthroplasty are well accepted surgical options, and

(f) expressed the opinion that, with appropriate treatment, the applicant will return back to all her normal activities, including return back to her full occupational duties without restriction.

1. Considering the evidence as a whole, I prefer and accept the evidence of the applicant's treating orthopaedic surgeon, Dr Alttahir, because:

(a) as the applicant's treating surgeon, I consider that he is well-placed to have a good understanding of the applicant's current symptoms, functional restrictions and the underlying pathology which is demonstrated by the imaging;

(b) Dr Alttahir has provided a comprehensive, sensible and compelling explanation for the longevity of the applicant's ongoing symptoms and functional restrictions despite various conservative treatment;

(c) Dr Alttahir's opinion that the genu varum is causing medial compartment overload, which is compounding meniscal tear and chondral damage of the left knee, and is contributing to the applicant's pain, provides a logical and likely explanation for the failure of various conservative treatments including two previous arthroscopic surgeries to provide any enduring relief in the applicant's left knee symptoms;

(d) Dr Alttahir has provided a comprehensive, sensible and compelling explanation of how the surgery would address the applicant's underlying pathology and provide symptomatic relief for the applicant;

(e) Dr Alttahir's opinion is supported by Dr Soo who has also provided a considered explanation, and

(f) I do not accept the respondent's submission that the opinions of Dr Alttahir and Dr Soo should not be given any weight because they did not consider clinical records which indicated that the applicant reported left knee symptoms some two weeks prior to the accepted injury because they were clearly aware of the underlying pre-existing degenerative condition.

1. In the circumstances, having regard to the evidence as a whole, I am satisfied on the balance of probability that the surgery is reasonably necessary.

Whether the treatment is reasonably necessary as a result of the injury

1. In the absence of any evidence to the contrary, I accept that the applicant did not have any left knee symptoms until several weeks prior to the accepted injury. The applicant was functionally well and employed full-time prior to the accepted injury.
2. The respondent concedes that the applicant sustained the accepted injury, which involved both a frank injury to the applicant's left knee and an aggravation of a pre-existing degenerative condition of her left knee.
3. The respondent has submitted that the applicant has recovered from the effects of the accepted injury and that that the surgery was reasonably necessary as a result of the accepted injury as required by s 60 of the 1987 Act.
4. In Elliot v Franklins Pty Ltd [2022] NSWPICPD 38 at [130] - [133], Phillips P held that the evidentiary onus to prove that an aggravation has ceased, rests with the party who makes the assertion, which is the respondent in this case.
5. The applicant's treating orthopaedic surgeon, Dr Mustafa Alttahir diagnosed symptomatic medial compartment overload due to varus malalignment with degenerative change.

Dr Alttahir stated that a varus malalignment of both knees is demonstrated by long leg alignment X-rays. Dr Alttahir noted that imaging shows that the left knee medial joint space is significantly narrowed compared to the lateral joint space, with spur formation, and that whilst right knee medial joint space narrowing and spur formation also present, it is less severe than the left. 6. Dr Alttahir stated that the applicant's current condition, being symptomatic medial compartment overload due to varus malalignment with degenerative change, is a direct result of the biomechanical consequences initiated by the accepted injury. Dr Alttahir gave evidence that the accepted injury caused a medial meniscus tear and subsequently accelerated degeneration in the medial compartment which, compounded by the applicant's underlying varus alignment, led to a cascade of persistent and progressive symptoms. On that basis, Dr Alttahir opines that the surgery is required because of the accepted injury. 7. Dr Alttahir gave evidence that the accepted injury has not resolved, noting that the applicant continues to suffer from significant medial knee pain, which interferes with her daily function and that, on clinical examination, there is clear evidence of varus deformity, anterior laxity, localized tenderness over the medial joint line, and radiographic signs of medial joint space narrowing. Dr Alttahir stated that those findings are not indicative of a resolved condition but rather demonstrate persistent and progressive pathology. 8. Significantly, Dr Alttahir stated that, the pattern and severity of the applicant's symptoms are not consistent with pre-existing or age-related degeneration alone, and instead, they reflect the biomechanical and structural consequences of the accepted injury, which initiated the deterioration and has led to the applicant's current level of impairment. 9. Dr Alttahir opines that the genu varum is causing medial compartment overload, which is compounding meniscal tear and chondral damage of the left knee, and is contributing to the applicant's pain, and that was not addressed by the previous arthroscopic surgeries. 10. Dr Gavin Soo, orthopaedic surgeon, independent medical expert qualified by the applicant, agreed with Dr Alttahir's opinion, noting the longevity of the applicant's left knee symptoms despite various conservative treatment, the findings on MRI and the applicant's age. 11. Dr Raymond Wallace, orthopaedic surgeon, independent medical expert qualified by the respondent, opined that the accepted injury has now recovered and the applicant's current left knee symptoms and restrictions are caused only by the underlying degenerative condition. 12. Considering the evidence as a whole, I prefer and accept the evidence of the applicant's treating orthopaedic surgeon, Dr Alttahir, because:

(a) as the applicant's treating surgeon, I consider that he is well-placed to have a good understanding of the applicant's current symptoms, functional restrictions and the underlying pathology which is demonstrated by the imaging;

(b) Dr Alttahir has provided a comprehensive, sensible and compelling explanation for the longevity of the applicant's ongoing symptoms and functional restrictions despite various conservative treatment;

(c) Dr Alttahir's opinion that the genu varum is causing medial compartment overload, which is compounding meniscal tear and chondral damage of the left knee, and is contributing to the applicant's pain, provides a logical and likely explanation for the failure of various conservative treatments including two previous arthroscopic surgeries to provide any enduring relief in the applicant's left knee symptoms;

(d) Dr Alttahir has provided a comprehensive, sensible and compelling explanation of how the surgery would address the applicant's underlying pathology and provide symptomatic relief for the applicant;

(e) Dr Alttahir's opinion is supported by Dr Soo who has also provided a considered explanation;

(f) I do not accept the respondent's submission that the opinions of Dr Alttahir and Dr Soo should not be given any weight because they did not consider clinical records which indicated that the applicant reported left knee symptoms some two weeks prior to the accepted injury because they were clearly aware of the underlying pre-existing degenerative condition, and

(g) I consider that it is significant that although the applicant has varus deformity in both legs, the applicant's evidence and the medical evidence demonstrates that only the left knee, which was the subject of the accepted injury, is symptomatic.

1. I note that the accepted injury does not have to be the only, or even a substantial, cause of the need for the surgery before the cost of that treatment is recoverable under s 60 of the 1987 Act.
2. In the circumstances, having regard to the evidence as a whole, and adopting a commonsense evaluation of the causal chain, I am satisfied on the balance of probability that the applicant did not recover from the effects of the accepted injury to the applicant's left knee and that the surgery is reasonably necessary as a result of the accepted injury.
3. I am satisfied that the accepted injury materially contributed to the need for the surgery.

1. For all the reasons set out above, I find as follows:

(a) the applicant did not recover from the effects of the accepted injury to the applicant's left knee on 6 July 2021, and

(b) the left knee arthroscopy, HTO and allograft and plate fixation recommended by Dr Mustafa Alttahir in his report dated 26 May 2025 and by Dr Gavin Soo in his report dated 7 July 2025 is reasonably necessary treatment as a result of the accepted to the applicant's left knee on 6 July 2021, pursuant to s 60 of the 1987 Act.

1. On that basis, it is appropriate to make the following orders:

(a) in accordance with s 60 of the 1987 Act_,_ the respondent to pay the future costs of and incidental to left knee arthroscopy, HTO and allograft and plate fixation and ancillary expenses as recommended by Dr Mustafa Alttahir in his report dated 26 May 2025 and by Dr Gavin Soo in his report dated 7 July 2025.

[1] [1986] NSWCC2; [1986] NSWCC 2; (1986) 2 NSWCCR 32.

[2] [2014] NSWWCCPD 72.

[3] [1986] NSWCC2; [1986] NSWCC 2; (1986) 2 NSWCCR 32.

[4] [1997] NSWCC 1; 14 NSWCCR 233.

[5] (1994) 35 NSWLR 452; 10 NSWCCR 796.

[6] (1994) 10 NSWCCR 796 at [810].

[7] [2015] NSWWCCPD 49 at [57].