Table 1.
Patient data
| Variable | The ERP group | The repair group | The no-repair group | p Value |
|---|---|---|---|---|
| Period in which primary THA was performed | August 2003 to May 2005 | May 2000 to July 2003 | August 1997 to April 2000 | |
| Number of patients (number of hips) | 196 (220) | 243 (282) | 118 (168) | |
| Age (years)* | 45.6 ± 14.6 | 47.6 ± 13.8 | 49.2 ± 15.1 | 0.474 |
| Gender (male:female) | 124:72 | 149:94 | 75:43 | 0.493 |
| Weight (kg)* | 64.1 ± 11.9 | 63.7 ± 12.7 | 62.4 ± 12.4 | 0.682 |
| Body mass index (kg/m2)* | 24.9 ± 8.5 | 23.9 ± 8.2 | 24.1 ± 7.9 | 0.648 |
| Preoperative diagnosis (number of hips) | ONFH (182); OA (26); other (12) | ONFH (199); OA (62); other (21) | ONFH (119); OA (42); other (7) | |
| Prosthesis† (number of hips) | Corail (94); Summit (66); VerSys (34); CLS (26) | VerSys (117); AML (65); other (21) | Mallory/Head (63); Omnifit (41); Centralign (22); other (42) |
*Mean ± standard deviation; †AML® Total Hip System (DePuy Orthopaedics, Inc, Indianapolis, IN); Centralign® (Zimmer, Inc, Warsaw, IN); CLS® (Centerpulse™, Bern, Switzerland); Corail® Total Hip System (DePuy); Mallory-Head® Hip System (Biomet Inc, Warsaw, IN); Omnifit® (Stryker Orthopaedics, Kalamazoo, MI); Summit™ Tapered Hip System (DePuy); VerSys® (Zimmer); ERP = external rotator preservation; OA = osteoarthritis; ONFH = osteonecrosis of the femoral head.