Table II.
Baseline characteristics of 94 patients undergoing revision of a Birmingham metal-on-metal resurfacing or total hip arthroplasty by procedure type.
| Characteristic | Cup retention and dual-mobility | Acetabular revision | Overall | p-value |
|---|---|---|---|---|
| N | 53 | 41 | 94 | |
| Mean age, yrs (range) | 68.3 (36 to 87) | 62.0 (33 to 75) | 65.5 (33 to 87) | < 0.001*† |
| Male:Female, n | 27:26 | 14:27 | 41:53 | 0.047*‡ |
| Mean time from last procedure, mths (range) | 143.7 (75 to 277) | 113.0 (59 to 191) | 129.9 (59 to 277) | < 0.001*† |
| Primary implant type, n (%) | ||||
| Birmingham Resurfacing | 11 (20.8) | 18 (43.9) | 29 (38.9) | |
| Synergy (Smith & Nephew)/Birmingham THA | 40 (75.5) | 22 (53.7) | 62 (66.0) | |
| SL Plus (Smith & Nephew) Stem/Birmingham THA | 1 (1.9) | 1 (2.4) | 2 (2.1) | |
| CPCS Stem (Smith & Nephew)/Birmingham THA | 1 (1.9) | 0 (0) | 1 (1.1) | |
| Preoperative MRI, n (%) | 49 (92.5) | 37 (90.2) | 86 (91.5) | |
| Collection on MRI, n (%) | 45 (91.8) | 26 (70.3) | 71 (82.6) | 0.009*‡ |
| Mean maximum diameter of collection, cm (range) | 6.5 (1.5 to 14.0) | 5.9 (1.0 to 12.0) | 6.3 (1.0 to 14.0) | 0.455† |
*
Significant at 5% level, no adjustment for multiple testing.
†
Mann-Whitney U test.
‡
Chi-squared test.
THA, total hip arthroplasty.