Presentation
Pain in proximal and distal calf. Denies history of trauma.
Patient Data
Spindle-shaped, mildly expansile sclerotic lesion with sharp borders in the lateral aspect of the distal tibial metadiaphysis. No periosteal reaction.
Due to focal tenderness on palpation of the distal tibia, a bone scan was done.
Mild radiotracer uptake in distal right tibia corresponding to the location of the lesion on plain film.
Eccentric lesion in lateral aspect of distal tibial diametaphysis. Lesion has sharply demarcated lobulated border, expands cortex mildly but does not violate its border or cause periosteal reaction. Intermediate T1 signal intensity (SI) and very low T2 SI; no contrast enhancement.
Characteristics of a benign lesion, most probably a healing non-ossifying fibroma (NOF).
At lower edge of scan, tiny structure in the tibiotalar joint, devoid of signal on all sequences - probably a loose body.
Case Discussion
As exemplified here, healing non-ossifying fibroma can exhibit mild radiotracer uptake on bone scan.
At MRI, it has low signal intensity on all sequences.
To complete the picture: Knee MRI (not included) showed a compression fracture of the posterolateral rim of the tibial plateau with adjacent bone marrow edema in the tibial epiphysis and lateral femoral condyle.