Table 2.
Analytical sample sizes and cases revised by femoral head material and head size
| Head size | Femoral head material | |
|---|---|---|
| Ceramic | Metal | |
| Revision | N = 6097, revised = 128 (2.1%) | N = 22,675, revised = 515 (2.3%) |
| < 32 mm | N = 468, revised = 9 (1.9%) | N = 2880, revised = 101 (3.5%) |
| 32 mm | N = 2072, revised = 61 (2.9%) | N = 8476, revised = 193 (2.3%) |
| 36 mm | N = 3239, revised = 49 (1.5%) | N = 10,242, revised = 194 (1.9%) |
| > 36 mm | N = 318, revised = 9 (2.8%) | N = 1077, revised = 27 (2.5%) |
| Dislocation | N = 4331, dislocation = 42 (1.0%) | N = 15,292, dislocation = 196 (1.3%) |
| < 32 mm | N = 249, dislocation = 7 (2.8%) | N = 1215, dislocation = 16 (1.3%) |
| 32 mm | N = 1507, dislocation = 17 (1.1%) | N = 5633, dislocation = 80 (1.5%) |
| 36 mm | N = 2363, dislocation = 17 (0.7%) | N = 7620, dislocation = 85 (1.2%) |
| > 36 mm | N = 212, dislocation = 1 (0.5%) | N = 824, dislocation = 15 (2.1%) |
Followup time for implants as it pertains to revision (in years): median = 4.6, SD = 3.4, maximum = 11.6 (ceramic < 32); median = 3.2, SD = 2.8, maximum = 11.2 (ceramic = 32); median = 2.05, SD = 1.8, maximum = 9.9 (ceramic = 36); median = 1.9, SD = 1.2, maximum = 5.5 (ceramic > 36); median = 5.9, SD = 3.5, maximum = 12.7 (metal < 32); median = 3.8, SD = 2.9, maximum = 12.6 (metal = 32); median = 2.8, SD = 2.2, maximum = 11.5 (metal = 36); and median = 2.8, SD = 1.7, maximum = 9.9 (metal > 36).