Biocompatibility of Delrin 150: a creep-resistant polymer for total joint prostheses.

A thermoplastic polymer, Delrin 150 (polyoxymethylene homopolymer), with creep resistance ten times that of ultrahigh-molecular-weight polyethylene, is used as a material for total joint prostheses. A study was made of the local and systemic host response to this polymer when implanted in three different mammalian species. 316 LC stainless steel was used as a control.

Total surface hip arthroplasty in dogs using a fiber metal composite as a fixation method.

A total hip surface replacement was performed on 13 adult mongrel dogs using a porous fiber metal composite for fixation to bone. Titanium fiber composite rings were molded onto cylindrical acetabular prostheses, and cobalt-chrome fiber inserts were sintered onto the cast cobalt-chrome femoral components. The animals were allowed unrestricted walking.

A canine cementless total hip prosthesis model.

To evaluate a porous fiber titanium composite as a fixation method, total hip arthroplasty was performed in 13 large male mongrel dogs. In seven both acetabular and femoral composites were fixed with a porous titanium fiber composite, and in the other six the acetabulum was fixed with acrylic cement. The animals were killed one, three, and six months following implantation.