Sanders v Hillier  NSWDC 192 arose from an orthopaedic spinal procedure following which the patient developed a bowel obstruction requiring surgery and extensive medical treatment. The allegations of negligence appear to have shifted somewhat during the hearing, however in general terms the concern was in relation to the post operative care and the referral of the patient to a physician rather than a surgeon.
The judgment at  onwards focuses on the section 5O defence, however careful reading suggests that breaches of the duty of care were not found in any event. That is clearer at , ,  and .
The passage at  seems to suggest that the plaintiff bore the onus of proving the section 5O defence elements, which appears inconsistent with the approach by the Court of Appeal in Dobler v Halverson  NSWCA 335 at . Quoting from Giles JA:
In this sense, s 5O provides a defence. The plaintiff will usually call his expert evidence to the effect that the defendant’s conduct fell short of acceptable professional practice, and will invite the court to determine the standard of care in accordance with that evidence. He will not be concerned to identify and negate a different professional practice favourable to the defendant, and s 5O does not require that he do so. The defendant has the interest in calling expert evidence to establish that he acted according to professional practice widely accepted by peer professional opinion, which if accepted will (subject to rationality) mean that he escapes liability.