Case History: A patient in her 7th decade of life presented with a right lateral thigh mass.The lump had been present for several months and increasing in size and tenderness. The patient had a history of multiple intramuscular antibiotic injections in the lateral thigh, near the location of the mass one year prior.
The lump had been present for several months and was increasing in size and tenderness.
Figure 1. A longitudinal image of the right lateral thigh demonstrated an oval, dense, hypoechoic, soft tissue mass with multiple echogenic foci.
Figure 2. A longitudinal image of the right lateral thigh demonstrated a linear echogenic mass with irregular borders and posterior acoustic shadowing.
Figure 3. An X-ray of the right thigh showed a heterotopic calcification lateral to the right femur.
Diagnosis: Myositis ossificans with superficial benign fibrovascular and adipose soft tissue mass
An ultrasound guided soft tissue core biopsy was performed on the superficial soft tissue thigh mass.
Myositis ossificans is a bone growth that forms in large muscle, most commonly the thigh.
