Table 4.
Representative values for bone histomorphometry in vitamin D and phosphate deficiency osteomalacia.
| Measurement | Vitamin D deficiency | Phosphate deficiency | Reference range |
|---|---|---|---|
| OS/BS (%) | 61.3 ± 18.0 | 70.1 ± 15.9 | 21 ± 11 |
| O·Th (μm) | 29.7 ± 10.5 | 38.0 ± 12.2 | <12.5 |
| OV/BV (%) | 21.7 ± 11.5 | 33.6 ± 19.1 | 2.6 ± 1.4 |
| ES/NOS (%) | 5.27 ± 3.59 | 1.99 ± 1.53 | 4 ± 2 |
| TBV/TV (% TV) | 24.4 ± 9.97 | 26.4 ± 16.1 | 20 ± 6 |
| CBV/TV (%) | 84.1 ± 23.4 | 92.5 ± 45.7 | 94.5 ± 2.5 |
| C·Th (cm) | 0.51 ± 0.35 | 0.94 ± 0.71 | 1.27 ± 0.37 |
OS: Osteoid surface; BS: bone surface; O·Th: Osteoid thickness; OV: Osteoid volume; ES: Eroded surface; NOS: Non-osteoid surface; BV: Trabecular bone volume; TV: Total tissue volume; CBV: Cortical bone volume; C·Th: Cortical thickness.
Note higher mean values for OS, O·Th, OV, TBV, and CBV in phosphate deficiency osteomalacia, and lower mean value for C·Th in vitamin D deficiency osteomalacia, a characteristic feature due to associated secondary hyperparathyroidism.
Differences in bone volumes and C·Th are not significant since the phosphate deficiency osteomalacia group is a mixture of both hereditary and acquired (tumor induced and tenofovir treated) hypophosphatemic osteomalacia. Bone volumes C.Th. are high in hereditary forms, but are low in the acquired forms. (Rao, SD, unpublished data).