A locking implant is provided for a long bone. The locking implant comprises a head portion, a stem portion extending from the head portion, and an anchor disposed at an end of the stem portion for engagement within a resected long bone. The anchor defines at least one locking feature, such as a cam, configured to engage an interior of the resected long bone upon rotation of the implant, thereby locking the head portion to the long bone. The implant may comprise a two component modular design. Methods of locking the implant to a long bone structure are also provided.
