Fibro-Osseus Pseudotumor of the Digit: A Case Report and Review of Literature

Abstract

Introduction: Bony subungual growths arising on the digital tip are uncommon. Among these, subungual exostosis is a common cause.

Case presentation: We describe a 35-year-old-male patient with a rare occurrence of a fibro-osseus pseudotumor of the digit. It presents with reactive intramembranous ossification, with no continuity with the distal phalanx, helping differentiate it from a subungual exostosis. The patient presented with an asymptomatic subungual growth, lifting up the nail plate distally causing onycholysis. The characteristic clinical, radiological, and histopathological features of the case are described, which helped confirm the diagnosis.

Conclusion: Cases with fibro-osseus pseudotumor of the digit reported in literature are reviewed comprehensively. The factors helping differentiate this from the other bony tumors affecting the distal phalanx, including subungual exostosis, myositis ossificans, and osteosarcoma are also highlighted.

Keywords: Fasciitis ossificans; Fibro-osseus pseudotumor of the digit; Florid reactive periostitis; Intramembranous reactive bone formation; Periosteal nodular fasciitis; Superficial myositis ossificans of distal extremities.