An intramedullary implant including an elongated body, a first groove in the body for varying the geometric stiffness of the body; and a second groove in the body for varying the geometric stiffness of the body. The first and second groove have varying cross-sectional shapes whereby the geometric stiffness...http://www.google.com.au/patents/US5509935?utm_source=gb-gplus-sharePatent US5509935 - Intramedullary implant with optimized geometric stiffness
