Plantar osteochondroma of the metatarsal bone: A case report and brief literature review

Osteochondromas are the most common benign bone tumors, typically arising from the metaphysis of long bones during skeletal development; however, their occurrence in the small bones of the foot, particularly the metatarsals, is exceedingly rare. We report the case of a 32-year-old female who presented with a seven-month history of a slowly enlarging, firm plantar mass and progressive mechanical pain along the medial arch of the left foot. Radiographic and cross-sectional imaging demonstrated a sessile osteochondroma arising from the plantar-medial aspect of the second metatarsal neck, exhibiting the pathognomonic corticomedullary continuity with the host bone and an 8-millimeter cartilaginous cap without aggressive features. 
Following multidisciplinary tumor board review, the patient underwent marginal en bloc excision through a plantar-medial approach, resulting in complete resolution of symptoms at twelve months postoperatively. Histopathological and molecular studies confirmed the benign nature of the lesion and definitively excluded its principal mimickers, including bizarre parosteal osteochondromatous proliferation. 
This case illustrates that osteochondroma should be considered in the differential diagnosis of chronic plantar foot pain in adults, even in the absence of hereditary multiple exostoses. It further emphasizes the indispensable role of multimodal imaging, multidisciplinary evaluation, and meticulous surgical planning in achieving safe and durable functional recovery.