A unique presentation of the rare Nora’s lesion, symptomatic bizarre parosteal osteochondromatous proliferation: A case report

Abstract

Bizarre parosteal osteochondromatous proliferations, also known as Nora’s lesions, are rare benign tumors with a high recurrence rate. They are often difficult to identify because of their similar appearance to other tumors. We describe a 25-year-old healthy female patient with bizarre parosteal osteochondromatous proliferations in an uncommon location on the pelvic ilium, presenting with unique clinical findings of abdominal pain and femoral paresthesia and showing atypical radiographic findings. To the best of our knowledge, this is one of the very few cases ever reported in the literature of Nora’s lesion in this particular location and possibly the first case ever with this specific presentation. The lesions’ radiographic images, combined orthopedic and general surgery procedures, and histological analysis are detailed. The patient’s continued 4-year follow-up has demonstrated no symptoms or evidence of recurrence.