Going round the twist – causation for consequential injuries

Taylor v Ongmac Trading Pty Limited [2022] NSWPIC 42 (3 February 2022)

The Applicant suffered an accepted injury to his right knee in early 2019, being a tear of the posterior horn of the right medial meniscus and an associated Baker’s cyst. He subsequently underwent arthroscopic surgery on 2 July 2020.

After attending a physiotherapist appointment for his injury on 28 July 2020, the Applicant visited a pub. While walking outside, his right foot caught on a foot rail, causing his right leg to twist resulting in a further right knee injury (“the second injury”). An MRI scan identified a large tear in a previously undamaged part of medical meniscus.

The Applicant sought approval from the Respondent for a further right knee arthroscopy as a result of the second injury. The Respondent disputed the claim relying upon IME evidence which considered that the second injury was a fresh injury, related entirely to the incident in the pub.

Issues for determination

Member Wynyard considered that it was incumbent on the Applicant to establish that his accepted injury materially contributed to the condition of his knee following the incident in the pub, relying upon the principle that a consequential condition “is one that, applying a common sense evaluation of the causal chain, has resulted from an earlier injury. It is not an “injury” as defined by [Section 4 of the 1987 Act]…”.

Member Wynyard set out the 3 guiding categories of causation for a consequential injury, as identified by Malcolm CJ in State Government Insurance Commission v Oakley (1990) 10 MVR 570 (“Oakley”):

1. Where the later injury results from a subsequent accident that would not have occurred had the victim not been in the physical condition caused by the earlier accident, the second injury should be treated as having a causal connection with the earlier accident.
2. Where an earlier injury is exacerbated by a subsequent injury, there will be a causal connection … unless it can be shown that some part of the subsequent damage would have been occasioned even if the original injury had not occurred.
3. Where … the subsequent injury would have occurred whether or not the victim had suffered the original injury and the damage sustained … includes no element of aggravation of the earlier injury, there will be no causal connection ….

Submissions

The Applicant submitted that the mechanism of injury for the further tear was rotational instability, which led to a twisting action. He also disputed the Respondent’s evidence that he had made a “full recovery” by the date of the second injury, referring to contemporaneous treating evidence that he had recently been referred for physiotherapy and was advised to return to light duties only.

The Applicant submitted that the Respondent’s evidence erroneously addressed whether employment was a substantial contributing factor to the second injury, rather than his susceptibility to further knee injury resulting from the surgery or the common sense evaluation of the casual chain.

The Applicant further submitted that the meniscal re-tear associated with the second injury fell within category 2 of Oakley and was therefore was causally connected to his initial accepted injury.

The Respondent submitted that there was no evidence that the Applicant had been left with rotational instability in the knee following his initial arthroscopy. The Respondent further submitted that the issue of susceptibility was not relevant as the sole cause of the second injury was a twisting motion, being an independent act which did not involve an aggravation of the initial injury.

The Respondent therefore submitted that the 3^rd category in Oakley applied.

Decision

Member Wynyard found that:

• The contemporaneous treating evidence demonstrated that the Respondent’s medical evidence was in error when it found that the initial work injury had “adequately resolved”, prior to the second injury.
• The Respondent’s evidence did not address the question of susceptibility to further injury resulting from the first surgery, or whether the second injury was consequential to same.
• The Applicant’s susceptibility to further injury materially contributed to the damage he sustained in the second incident, which caused an aggravation of his initial work injury.
• The Applicant’s injury could be categorised within the second category in Oakley as, although it would have occurred had he been in normal health, the damage he sustained had been greater because of aggravation of his initial work injury.
• Whether employment was a substantial or the main contributing factor had no relevance to causation for a consequential condition.

Ultimately, Member Wynyard ordered the Respondent to pay the costs of, and associated with, the further right knee arthroscopy proposed by Dr Prodger.

Ramifications

This decision highlights the significant difference between the tests of causation for injury defined under Section 4 of the 1987 Act and a consequential injury. It also emphasises the importance of obtaining medical evidence which addresses the relevant test of causation.

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