Table 3.
Measurements of proximal femoral anatomy, absolute differences, and percent asymmetry per ethnicity
| Measurement | Ethnicity | Diameter* (mm) | 95% CI | Absolute difference*,† (mm) | 95% CI | Percent asymmetry‡ | 95% CI |
|---|---|---|---|---|---|---|---|
| AP measurements | |||||||
| Femoral head | Caucasian | 52.0 ± 4.7 | (50.9, 53.0) | 1.0 ± 0.8 | (0.8, 1.1) | 1.9 ± 1.7 | (1.5, 2.3) |
| African-American | 52.1 ± 5.9 | (50.8, 53.4) | 0.7 ± 0.5 | (0.6, 0.8) | 1.4 ± 1.1 | (1.2, 1.7) | |
| Femoral neck | Caucasian | 36.6 ± 4.2 | (35.7, 37.5) | 1.2 ± 0.8 | (1.0, 1.4) | 3.4 ± 2.4 | (2.9, 3.9) |
| African-American | 36.4 ± 4.8 | (35.4, 37.5) | 1.0 ± 0.7 | (0.8, 1.1) | 2.7 ± 2.0 | (2.7, 3.2) | |
| Femoral shaft | Caucasian | 35.0 ± 3.8 | (34.1, 35.8) | 1.0 ± 0.8 | (0.8, 1.1) | 2.8 ± 2.2 | (2.3, 3.3) |
| African-American | 35.3 ± 4.1 | (34.4, 36.2) | 1.0 ± 0.7 | (0.8, 1.2) | 2.8 ± 2.0 | (2.4, 3.2) | |
| Cephalocaudal measurements | |||||||
| Femoral head | Caucasian | 37.5 ± 3.3 | (36.8, 41.3) | 0.6 ± 0.5 | (0.4 0.7) | 1.5 ± 1.5 | (1.2, 1.8) |
| African-American | 38.2 ± 4.4 | (37.3, 39.2) | 0.5 ± 0.4 | (0.4, 0.6) | 1.3 ± 1.1 | (1.0, 1.5) | |
| Femoral neck | Caucasian | 21.6 ± 2.4 | (21.1, 22.1) | 0.7 ± 0.6 | (0.6, 0.9) | 3.5 ± 2.9 | (2.8, 4.1) |
| African-American | 22.4 ± 3.4 | (21.7, 23.2) | 0.7 ± 0.5 | (0.5, 0.6) | 3.2 ± 2.4 | (2.7, 3.7) | |
* The data are given as mean ± SD; †absolute difference = difference between maximum and minimum of left and right; ‡percent asymmetry = (maximum − minimum)/(average of maximum and minimum) × 100.