Bizarre Parosteal Osteochondromatous Proliferation (Nora's Lesion) of the Sesamoid: a Case Report

• Published in: Foot & ankle international Vol. 21; no. 5; pp. 408 - 412
• Main Authors: Harty, J.A., Kelly, P., Niall, D., O'Keane, J.C., Stephens, M.M.
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-05-2000
• Subjects: Adult; Bone Neoplasms - diagnosis; Bone Neoplasms - pathology; Bone Neoplasms - surgery; Female; Follow-Up Studies; Humans; Magnetic Resonance Imaging; Osteochondromatosis - diagnosis; Osteochondromatosis - pathology; Osteochondromatosis - surgery; Periosteum - pathology; Sesamoid Bones - diagnostic imaging; Sesamoid Bones - pathology; Sesamoid Bones - surgery; Tomography, X-Ray Computed; Treatment Outcome
• ISSN: 1071-1007; 1944-7876
• DOI: 10.1177/107110070002100509

We report the a case of Nora's lesion (Bizarre Parosteal Osteochondromatous Proliferation) of the sesamoid. A 32-year-old woman presented with a painless, enlarging mass of two years duration on the plantar aspect of the first metatarsophalangeal joint of the left foot. Radiographs, Computerized Tomographs and Magnetic Resonance images, initially suggested a parosteal osteosarcoma arising from the tibial sesamoid. The mass was excised, and a histological diagnosis of Bizarre Parosteal Osteochondromatous Proliferation of bone (Nora's lesion) was made. The aggressive growth of this lesion may suggest a neoplasm clinically. Histological features, however, are those of a reactive lesion.