| Site | Reasons (samples) |
|---|---|
| PA Spine | scoliosis |
| focal sclerosis, osteophytes, fracture | |
| body thickness | |
| extremely low bone mass | |
| Hip | anatomy rotation |
| focal calcifications, bony sclerosis, osteophytes | |
| body thickness | |
| extremely low bone mass | |
| Arm | anatomy rotation |
| focal calcifications, bony sclerosis, osteophytes | |
| motion | |
| extremely low bone mass |