Bizarre Parosteal Osteochondromatous Proliferation (Nora's Lesion) Of the Second Proximal Phalanx Encasing the Flexor Tendon of the Foot: A Case Report.

INTRODUCTION: Bizarre Parosteal Osteochondromatous Proliferation (BPOP) is a rare benign lesion commonly referred to as Nora's lesion. It typically affects adults in their 20s-30s. Due to its aggressive local invasion, it can be confused with some malignant tumors, including chondrosarcoma. Nora's lesion can be diagnosed radiographically, and its diagnosis is confirmed with an excisional biopsy.

CASE REPORT: A 40-year-old Bahraini male complained of swelling over the metatarsal head of the second digit, increasing in size over a year. He also complained of a reduced range of motion of the second toe and a pins-and-needles sensation affecting the entire toe. Plain X-ray, computed tomography, and magnetic resonance imaging were done, showing findings suggestive of bizarre parosteal osteochondromatous. The lesion was encasing the flexor tendon of the second digit. He was treated with surgical excision, and histopathology confirmed the diagnosis of BPOP.

CONCLUSION: We report on a rare presentation of BPOP in the second proximal phalanx of a male in his 40 s. The patient underwent a wide local excision, and the diagnosis was confirmed with histopathology.