A bone sizing guide for assessing the size of an end of a bone includes a body (6) having a foot component (2) with a first surface (10) to rest against an end surface of the bone and a foot (12) extending transverse to the first surface to contact a side surface of the bone. A superstructure (40) is coupled to the body so that the superstructure can slide relative to the body towards and away from the body, at least one of the superstructure and the body being adjustable so that the rotational direction in which the superstructure extends relative to the foot component about a first axis extending transverse to the first surface is adjustable. A stylus (53) extends from the superstructure transverse to the first surface of the body, the stylus having a tip to contact a surface of the bone, and a scale (64) is coupled to or formed on a first one of the superstructure and the body. An indicator (52) is coupled to or formed on a second one of the superstructure and the body to identify a position on the scale. The identified position on the scale shifts as the superstructure slides towards or away from the body, and the identified position shifts as the superstructure rotates relative to the body without sliding motion between the superstructure and the body, such that the identified position on the scale is indicative of the distance between the stylus and the foot.Linvention concerne un guide de dimensionnement dos pour évaluer la dimension dune extrémité dun os, lequel guide de dimensionnement dos comprend un corps (6) ayant un composant de pied (2) comportant une première surface (10) destinée à reposer contre une surface dextrémité de los et un pied (12) sétendant de manière transversale à la première surface pour venir en contact avec une surface latérale de los. Une superstructure (40) est couplée au corps de telle sorte que la superstructure peut coulisser par rapport au corps vers et à distance du corps, au moins lun de la superstructure et du corps pouvant ê
