Development of optimized epoxy graphite implant for the total hip joint.

Various metal implants are available for total hip joint replacements. There are problems associated with the micromovement of the implants with bone and/or with bone cement and about ten percent failure cases are reported. The mechanical properties of the metal implants do not match with that of human bone in the femur resulting in a stress distribution in the femur different from one without implant. Many researchers are working with different materials like alloy materials with lower modulus of elasticity, ceramic, etc. The study conducted at S.D.S.M. & T. biomechanics laboratory investigates the feasibility of using epoxy graphite as an implant material. The mechanical properties of the implant material are being optimized using experimental and analytical methods. The reflection polariscope method (photo stress method) was used to determine the micromovement of the implant and the bone, and stress distribution in the femur subjected to cyclic loading. A finite element method was used to optimize the mechanical properties of the implant to obtain a stress distribution closer to the one without implant. An epoxy graphite implant with optimized mechanical properties is being manufactured and tests are in progress.