The increasing use of a cementless acetabular component with a total hip replacement requires the need for metal backing, but metal backing with cement in the author's use has been less than optimal. The intention, therefore, was to evaluate all cemented acetabular components, with and without metal backing, used by the author, to offer a standard by which other acetabular components can be compared. From 1969 to 1983, 238 Charnley, 141 Mueller, 555 T-28, 100 Miami Orthopaedic Surgical Clinic total hip replacements with cemented all-polyethylene acetabula, and 134 Miami Orthopaedic Surgical Clinic total hip replacements with a cemented metal-backed acetabula were performed and followed from 1 to 22 years. The cemented acetabular component failure rates for the Charnley, T-28, and all-polyethylene Miami Orthopaedic Surgical Clinic were 14%, 10%, and 9%, respectively. There was a 20% failure rate in the Mueller and metal-backed Miami Orthopaedic Surgical Clinic acetabular components. The Charnley (p < 0.0001), T-28 (p < 0.0001), all-polyethylene Miami Orthopaedic Surgical Clinic (p < 0.0001), and Mueller (p < 0.012) total hip replacements demonstrated statistically improved survival rates as compared with the metal-backed Miami Orthopaedic Surgical Clinic acetabular components. The Charnley (p < 0.0001) and T-28 (p < 0.0003) sockets survived statistically better than the Mueller sockets. The above clinical data and the reported linear wear rates of the cemented molded all-polyethylene acetabular components continue to support the rationale for cementing an all-polyethylene acetabular component as opposed to cementing a metal-backed component or using a metal-backed porous-coated prosthesis without cement.
Center for Hip and Knee Surgery, Mooresville, IN, and Department of Orthopaedic Surgery, Indiana University Medical Center, Indianapolis, IN.
Reprint requests to Merrill A. Ritter, MD, 1199 Hadley Rd, Mooresville, IN 46158.