TABLE 6
Percent Regional Distribution of Active Bone Marrow Mass by Skeletal Site
Percentage distribution of active bone marrow mass by skeletal site  (mean in %) | ||||
|---|---|---|---|---|
| Skeletal site | Present study (males) (n = 20) | Present study (females) (n = 20) | Present study (combined) (n = 40) | ICRP Publication 70 (7) reference values |
| Cranium | 2.7 | 4.3 | 3.5 | 7.6 |
| Mandible | 0.7 | 1.0 | 0.8 | 0.8 |
| Scapulae | 3.6 | 2.7 | 3.2 | 2.8 |
| Clavicles | 1.1 | 1.0 | 1.0 | 0.8 |
| Sternum | 3.2 | 2.9 | 3.0 | 3.1 |
| Ribs | 15.1 | 12.9 | 14.0 | 16.1 |
| Cervical vertebrae | 3.5 | 3.6 | 3.5 | 3.9 |
| Thoracic vertebrae | 16.9 | 16.5 | 16.8 | 16.1 |
| Lumbar vertebrae | 14.3 | 14.4 | 14.3 | 12.3 |
| Sacrum | 9.6 | 11.6 | 10.6 | 9.9 |
| Ossa coxae | 20.2 | 20.5 | 20.3 | 17.5 |
| Femora (proximal) | 6.3 | 6.1 | 6.2 | 6.7 |
| Humeri (proximal) | 2.9 | 2.5 | 2.7 | 2.3 |
| L2–L4 | 8.6 | 8.9 | 8.7 | Not defined |
Estimates are taken using Equation 8 with data of Table 1 (MVF and CF) and Table 6 (fractional spongiosa volumes).