What is the standard of care provided by a surgeon to a plaintiff in a surgical malpractice case?

The plaintiff pleads in the alternative to negligence that the defendant was in breach of a contract to her that he would in fact render her sterile. Generally speaking a physician undertakes to bring to his treatment skill, knowledge and judgment and to faithfully exercise these qualities. Unless there are special circumstances in the particular case where a physician may have given further undertakings there is no contractual relationship beyond this: see Wilson v. Swanson (1956), 1956 CanLII 1 (SCC), 5 D.L.R. (2d) 113 at p. 119, [1956] S.C.R. 804 at p. 811, per Rand J.: What the surgeon by his ordinary engagement undertakes with the patient is that he possesses the skill, knowledge and judgment of the generality or average of the special group or class of technicians to which he belongs and will faithfully exercise them.