Long-term follow-up of early Charnley cemented THAs demonstrates excellent survival (Table 1). New techniques in cementing have improved the quality of the femoral cement fixation and have shown consistently good performance at 10-year follow-up. Noncemented designs have not yet demonstrated similar long-term results. Recent reports reveal osteolysis in noncemented prostheses, which is observed earlier than in cemented designs. This implies a greater role for polyethylene debris in the etiology of osteolysis. Polyethylene debris is produced not only at the articulation but also at the nonarticular metal-polyethylene interface in modular metal-backed acetabular components. This results in the production of additional plastic debris. Metal backing has not demonstrated any clinical improvement in the long-term performance of cemented acetabular components. Furthermore, it may be detrimental due to decreased polyethylene thickness, increased stress within the polyethylene, and an increased rate of polyethylene wear of both the articular and nonarticular surfaces. Multiple reports have demonstrated that titanium alloy is not an acceptable articulating surface because it has a poor resistance to abrasion. It can result in severe metallosis in the periarticular tissues, leading to progressive osteolysis and early failure of the arthroplasty. Caution is suggested in the widespread application of polymodular femoral components because the production of metallic debris may prove excessive. Cemented THA remains the gold standard by which other methods of fixation must be assessed. The enviable long-term results with early cementing techniques and the Charnley prosthesis will be difficult to match, even with developing technology.
|Original language||English (US)|
|Number of pages||11|
|Journal||Orthopedic Clinics of North America|
|State||Published - Jan 1 1993|
ASJC Scopus subject areas
- Orthopedics and Sports Medicine