[This headnote is not to be read as part of the judgment]
The appellant was born with a condition known as a pars defect or dysplastic spondylolysis. The condition was asymptomatic until 2009 when the appellant was 15 years of age and she began to experience pain in her left hip. This was treated conservatively. She again developed pain in the left hip in March 2012 at 18 years old, for which her general practitioner referred her for X-rays, an ultrasound and orthopaedic review. A month prior, the appellant had commenced work at a child care centre, which required repetitive lifting from the ground to waist level.
The appellant's general practitioner referred her for X-rays of the hip and pelvis which were taken on 24 May 2012. Although (as was not disputed) the X-rays revealed the presence of the congenital pars defect, a report prepared by the respondent, a radiologist, failed to identify the defect. The appellant's orthopaedic surgeon, Dr Stening, was provided with the X-rays and also did not identify a pars defect, relying on the respondent's report; rather, Dr Stening made a diagnosis of left and right ASIS apophysitis, ordered conservative cortisone treatment and referred the appellant to a physiotherapist.
The appellant's symptoms did not abate and on 5 June 2013, she had an X-ray of her spine which demonstrated a forward slipping of one vertebral disc on another (known as 'spondylolisthesis') due to the pars defect. The appellant was referred to another orthopaedic surgeon who performed spinal surgery upon her as a matter of urgency. The appellant developed a secondary chronic pain syndrome as a direct consequence of the surgery, notwithstanding that (as was accepted) the surgery was performed competently.
The appellant brought proceedings against the respondent, alleging that his failure to identify either spondylolysis or spondylolisthesis constituted a breach of his duty of care, the consequence of which was that Dr Stening did not institute appropriate clinical management or investigation and she suffered progressive damage to her spine that could have been avoided if her condition had been properly diagnosed and treated from 24 May 2012. At trial, the respondent admitted that his failure to identify the pars defect constituted a breach of the duty of care that he owed the appellant, but denied that it caused the appellant's chronic pain syndrome.
Although the case was pleaded and, until the conclusion of the trial, conducted on the basis that the appellant's condition as at 24 May 2012 included spondylolisthesis, at the last minute it was contended that, as at that date, she suffered only the lesser condition of spondylosis. Had that been correct, and had she been treated appropriately for that condition, she may have been able to avoid the surgery that gave rise to the chronic pain syndrome.
Having regard to the expert evidence, the primary judge was unable to be satisfied that, on the balance of probabilities, earlier conservative intervention or management would have altered the progression of the appellant's condition or averted the need for surgery. Accordingly, the primary judge held that the appellant had not established a causal link between the respondent's failure to diagnose the appellant's condition and the need for the surgery and the consequent chronic pain syndrome.
On appeal, the appellant contended that the primary judge erred by: (1) failing to address the appellant's submissions on causation; (2) failing to provide adequate reasons on the issue of causation; (3) failing to make relevant findings on the issue of causation; (4) making errors in the factual analysis and reasoning underpinning the causation conclusion; (5) misdirecting himself in his analysis of the evidence of two medical practitioner witnesses by finding that their evidence "amounted to a loss of a chance".