Results of cemented metal-backed acetabular components: a 10-year-average follow-up study.
The clinical and radiographic results of 86 primary total hip arthroplasties performed in 74 patients from 1983 to 1987 with a cemented metal-backed acetabular component and a cemented collared straight femoral stem with a 32-mm head were reviewed at a mean follow-up of 10.1 years. Seven patients (9.2%) underwent acetabular component revision at a mean of 9.0 years after implantation; an additional 24 components (31.6%) demonstrated evidence of radiographic loosening, resulting in a total failure rate of 40.8%. Periacetabular radiolucencies were noted in Charnley zones at the following rates: 34.2% in zone I, 18.4% in zone II, and 27.6% in zone III. In addition, 18.4% and 38.2% of implants demonstrated evidence of migration and excessive polyethylene wear. Excessively vertical cup placement (>49 degrees inclination) at the time of initial arthroplasty was statistically correlated with polyethylene wear, implant migration, and fixation failure. A trend of increasing implant failure was also noted with decreasing polyethylene liner thickness. Periacetabular cement mantle thickness was not statistically correlated with subsequent component loosening or failure. Results of Kaplan-Meier survivorship analysis using revision as an endpoint showed 93.6% survivorship at 10 years and 88.4% at 12 years. The mean modified Harris hip scores were 46.9 preoperatively and 81.8 at final follow-up. The significant overall rates of radiographic loosening, migration, polyethylene wear, and implant revision confirm the suspected trend of increasing failure rates of cemented metal-backed acetabular components over time.
Chen
F S
FS
Department of Orthopaedic Surgery, Musculoskeletal Research Center, Hospital for Joint Diseases Orthopaedic Institute, New York, New York 10003, USA.
Di Cesare
P E
PE
Kale
A A
AA
Lee
J F
JF
Frankel
V H
VH
Stuchin
S A
SA
Zuckerman
J D
JD
D000077:Acetabulum; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods* / Q000706:statistics & numerical data; D001843:Bone Cements; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000000981:diagnostic imaging; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D011095:Polyethylenes; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D012086:Reoperation / Q000706:statistics & numerical data; D013997:Time Factors
D001843:Bone Cements; D011095:Polyethylenes