22 July 2025 Keith Rix 20 Case Updates Expert evidence and the materiality of a risk byKeith Rix Commentary Although this is an orthopaedic case and in which given its preliminary nature the expert evidence was not tested, it is helpful for experts in general as well as orthopaedic experts. It sets out the law on consent as established in not only Montgomery but also in McCullough. It touches on orthopaedic experts giving evidence in cases outside their own subspecialty. Learning points: There is a distinction to be drawn between the choice of treatment options on the one hand and the discussion of those options and the risks that come with them on the other. The Bolam test is central to the first but not the second. With regard to the second, it is for the patient to decide what risks he is willing to run. The doctor's duty is to take reasonable care to ensure that he is aware of any material risks in treatment and of any reasonable alternative or variant treatments so that the patient can make his informed decision. The test of materiality is patient centred, what the reasonable person in the patient's position would attach significance to. What risks associated with an operation were or should have been known to the medical professional in question is a matter falling within the expertise of medical professionals. Whether the patient should have been told about such risks by reference to whether they were material is a matter for the court to determine upon assessment of the materiality of the risk; the issue is not therefore the subject of the Bolam test and not something that can be determined by reference to expert evidence alone. A doctor is not under a duty to discuss a potential alternative treatment that he or she does not consider reasonable, providing that assessment is supported by a responsible body of medical opinion. All reasonable treatment, even if it is not preferred, must be discussed. Where an orthopaedic surgeon gives expert evidence in a case outside his sub-specialty it may be accorded less weight than that of an orthopaedic surgeon giving expert evidence in a case which falls within their sub-specialty. To continue reading you must be an EWI member, become a member and access exclusive content. Already a member? Login More links Link to the judgment Share Print Tags Legal testConsent to treatmentOrthopaedics11. Report Writing12. Responding to questions Related articles Podcast Episode 14: Reflections on the EWI Annual Conference 2025 Most unsatisfactory expert paediatric evidence Email chains, gross misconduct and the experts who count the cost Should a solicitor use track changes on my expert report An expert report that is entirely equivocal on the key issues is of little assistance to the court Switch article Frederick Ayinde, R (on the application of) v The London Borough of Haringey [2025] EWHC 1383 (Admin) Previous Article Comments are only visible to subscribers.