Table 1. Mean BAs (in Years) Overall and for Each of Five Groups of Hand-Wrist Bones of Children Determined According to BoneXpert.
| Age | n (M/F) |
Overall BA | Distal Radius and Ulna | Metacarpals | Proximal Phalanges | Middle Phalanges | Distal Phalanges | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Boys | Girls | Boys | Girls | Boys | Girls | Boys | Girls | Boys | Girls | Boys | Girls | ||
| 2–2.99 | 8/16 | 2.95 | 2.81 | 2.56 | 2.36 | 2.69 | 2.40 | 2.97 | 2.75 | 3.44 | 3.22* | 3.19 | 3.13* |
| 3–3.99 | 13/17 | 3.72 | 3.25 | 3.79 | 3.17 | 3.43 | 3.06 | 3.63 | 3.17 | 3.95 | 3.79 | 3.91 | 3.48 |
| 4–4.99 | 22/24 | 4.80 | 4.22 | 4.67 | 3.90 | 4.60 | 4.01 | 4.78 | 4.20 | 4.84 | 4.81 | 4.96 | 4.55 |
| 5–5.99 | 24/24 | 5.51 | 5.53 | 5.35 | 5.12 | 5.11 | 5.17 | 5.55 | 5.63 | 6.06 | 6.30* | 5.58 | 5.59 |
| 6–6.99 | 16/19 | 6.14 | 6.67 | 6.21 | 6.24 | 5.62* | 6.16 | 6.13 | 6.81 | 6.88 | 7.33* | 6.31 | 6.72 |
| 7–7.99 | 18/6 | 6.88 | 7.39 | 6.46* | 6.98 | 6.38* | 6.81 | 7.14 | 7.56 | 7.87 | 7.98 | 7.04 | 7.52 |
| 8–8.99 | 20/12 | 7.74 | 8.66 | 7.80 | 8.60 | 7.08* | 8.11 | 7.77 | 9.14 | 8.68 | 9.30 | 7.82 | 8.53 |
| 9–9.99 | 15/11 | 8.72 | 8.95 | 8.50 | 8.63 | 7.95* | 8.17* | 8.91 | 9.27 | 9.55 | 9.98* | 8.82 | 9.12 |
| 10–10.99 | 16/11 | 10.10 | 10.25 | 10.05 | 10.42 | 9.33 | 9.81 | 10.46 | 10.49 | 10.84 | 10.98 | 10.06 | 10.04 |
| 11–11.99 | 33/19 | 11.87 | 10.95 | 11.81 | 10.55* | 11.32 | 10.73* | 12.06 | 11.17 | 12.74* | 11.51 | 11.75 | 11.00 |
| 12–12.99 | 24/9 | 12.69 | 11.26 | 12.61 | 11.04 | 12.25 | 11.04 | 12.94 | 11.31 | 13.25* | 11.75 | 12.61 | 11.07 |
| 13–13.99 | 20/0 | 13.27 | 13.10 | 12.95 | 13.45 | 13.72 | 13.35 | ||||||
*Indicate significant difference (p < 0.05) between BA and CA. BA = bone age, CA = chronological age