Fibro-osseous pseudotumor of digits (FOPD) is an uncommon histological diagnosis. Clinical and imaging findings may resemble high-grade sarcoma or infection. We describe a patient with progressive pain and swelling at the dorsal surface of the first web space. MRI and CT imaging revealed an intramuscular heterogenous soft tissue mass defined by a mineralized peripheral ring. Core needle biopsy diagnosed FOPD. Eight months later a matured ossified nodule that was quite smaller than the initial soft tissue mass was excised. The patient is symptom free without local recurrence at 1 year follow up. Soft tissue masses of the hand pose a challenging diagnostic and therapeutic issue. An in depth interpretation of clinical, imaging and histology findings is important to avoid erroneous diagnosis and treatment.
Keywords: Fibro-osseous pseudotumor of digits; Infection; Myositis ossificans; Soft tissue sarcoma.