Chester v Afshar 
A client advised by a neurological expert to perform surgery on low back pain. It was complicated by Cauda Equina Syndrome. She sued the doctor for not informing the risk.
Judgment held: Although the risk of the operation going wrong would not at all have been changed had the patient been warned, it was the duty of the doctor to warn her. It is basic principle of good medical practice that adults should consent on a fully informed basis to surgery, aware of all risks.