Sintered Fiber Metal Composites as a Basis for Attachment of Implants to Bone

A fiber titanium composite has been developed and its potential application as a method of skeletal fixation for internal prosthetic devices has been studied. Titanium fibers, 0.19 millimeter in diameter, were cut in short lengths, compressed in dies to predetermined densities, and sintered under vacuum. The composite exhibited adequate strength and its compliance was larger than bone. Samples were implanted in the trochanteric and in the supracondylar areas of the femora of rabbits and dogs. Peripheral bone formation was evident at ten days, bone ingrowth was demonstrated at two weeks, and penetration deep into the samples was seen three weeks following implantation. The shear strength of the bond at the implant bone interface in the trochanteric region of dogs was measured hs tensile tests. The strength increased significantly until the second week and remained constant thereafter until twelve weeks following implantation. Average values were in the range of 20 kg/cm2. These findings are discussed in terms of the configuration of a prosthetic device. A fiber metal composite in the form of a thin sleeve surrounding ansd bonded to a central solid metal core would provide fixation to bone and uniform stress distribution at the implant bone interface.