Cementless total joint arthroplasty prostheses with titanium-alloy articular surfaces. A human retrieval analysis.

摘要: Surgical implants of titanium alloy (Ti-6Al-4V) have been found to be susceptible abrasive wear, resulting in the well-known phenomenon metallosis. In presence acrylic debris generated by loose joint arthroplasty prostheses, this wear is greatly increased. However, bone loss seen these cases has generally presumed due osteolytic effects particulate acrylic, not debris, which assumed biocompatible. To examine vivo titanium-alloy without added a comprehensive analysis was made cementless human prostheses with Ti-6Al-4V surfaces articulating on ultra-high molecular weight polyethylene (UHMWPE). Specimens, including synovium, pseudocapsule and additional soft tissues, periarticular bone, were retrieved from 22 hips two knees. Specimens examined histologic techniques, energy-dispersive X-ray analysis, electron microscopy. Serial sections evaluated for tissue ingrowth. Tissues surrounding all joints implanted more than one year showed some degree discoloration indicative metallosis, whereas after years synovium hypertrophic villiform. Histologic evaluation good fixation bony ingrowth vast majority cases, although location extent dependent numerous factors. Viability established fluorochrome labeling. despite biologic fixation, cavitary osteolysis frequently identified. These lesions filled sheets aggressive macrophages within matrix fibrous necrotic debris. Under polarized light fragments characteristic size. Osteoblast-mediated remodeling infrequently observed. Instead, resorbed along front contact granulomatous tissues filling cystic lesions. Visible burnishing observed every articular surface, linear relationship between time implanted. By covered "scratch gouge" pattern, similar sizes femoral heads as well total knee prostheses. This study demonstrates that combination UHMWPE, when used bearing surface results excessive both metal polymer.(ABSTRACT TRUNCATED AT 400 WORDS)