STRESS FRACTURE GRADING
| GRADE | XRAY | SPECT-CT BONE SCAN | MRI |
| 1 | normal | mild /diffuse increase in tracer uptake. CT normal |
Increased periosteal T2 signal. Normal marrow signal. |
| 2 | normal | moderately intense tracer uptake, mild sclerosis or thickening, but no fracture line | plus changes on STIR and T2 sequences |
| 3 | Visible line | intense (linear) focal tracer uptake with definite sclerosis or fracture line | plus bone marrow signal changes on T1 |
| 4 | Fracture or periosteal reaction | Intense transcortical uptake, cortical disruption, perisoteal thickening | Fracture line |
*for more information re MRI see here.