A patella drill guide includes a base with a flat patella bone-facing surface, a drill guide bore extending through the base, a cantilever spring member and a bone-gripping member. The cantilever spring member biases the bone-gripping member and the flat patella bone-facing surface toward each other. Flexing the cantilever spring member moves the bone-gripping member away from the flat patella bone-facing surface so that the drill guide can be placed on the patella. When the cantilever spring member is released, the patella is clamped between the bone-gripping member and the flat patella bone-facing surface. The drill guide may have sizing indicia and may be part of a kit including trial components to be mounted to the drill guide.