Abstract: A tibia-referenced system for objectively testing the integrity of the anterior and posterior cruciate ligaments of the knee with passive drawer, active drawer, and end point tests. Two simplified forms of the invention embody an elongated reference arm with a distal end pad that is fulcrumed against a distal region on the tibia and a proximal reference pad that rests on either the tibial tubricle or patellar bone structure, while a displacement indicator rod slidably mounted on the arm carries another proximal reference pad that rests on the other of these two bone structures adjacent the knee joint.

Abstract: In order to reduce the incidence of artificial joint failure at the interface where the prosthesis is bonded to the bone by cement, the artificial prosthesis is provided with openings, and is clamped in place to provide a peripheral seal around the end of the bone to which it is being secured. Then the cement is applied through the prosthesis under pressure, and the pressure is maintained until the cement hardens. The prosthesis may be provided with both input and output openings so that, as the cement is forced into the space between the prosthesis and the cortical bone structure, material including blood and marrow contents will be forced out the exit apertures and the pressurized cement will thereafter make good direct contact with both the bone and the prosthesis, to insure a lasting bond. The rim of the prosthesis and the matching bone surfaces may be specially prepared to provide a good pressure tight seal.