Noncemented total knee arthroplasty.

Extensive animal experimentation has proven porous titanium fiber composite to be an effective interface for direct attachment of prosthetic devices via bone ingrowth. Titanium has demonstrated excellent biocompatibility in long-term primate experiments. Utilizing this technology, a cementless total knee system has been developed. A pilot study of 34 knees demonstrated the feasibility of anchoring the tibial component without cement. A totally cementless unconstrained total knee replacement was designed with porous titanium fiber composite interfaces. Retention of the posterior cruciate ligament was an essential part of the design. A large range of sizes was chosen to allow precise fitting of individual patients with distribution of load over the maximum surface available. Early clinical results have been very encouraging. Patients have achieved excellent pain relief, rapid return of function, and range of motion exceeding previous designs.