MYCOLab Ai Logo - gold and army green

Bizarre parosteal osteochondromatous proliferation in the distal ulna where the lesion is continuous with the medullary cavity: a case report

Summary

An 11-year-old girl developed a rare type of benign bone tumor called BPOP (Bizarre parosteal osteochondromatous proliferation) on her wrist that unusually extended into the bone marrow. Doctors used imaging scans to diagnose the condition and surgically removed the tumor along with part of the bone. After surgery, the girl’s arm movement improved significantly, and one year later there were no signs the tumor had returned.

Background

Bizarre parosteal osteochondromatous proliferation (BPOP), also known as Nora’s lesion, is a rare benign bone tumor characterized by heterotopic ossification. Typically, BPOP lesions do not communicate with the medullary cavity, which helps distinguish them from other bone tumors such as osteochondroma. However, rare cases have been reported where BPOP lesions demonstrate continuity with the medullary cavity, presenting diagnostic challenges.

Objective

This case report presents an atypical BPOP case with reversed features compared to typical presentations, specifically demonstrating continuity of the lesion with the medullary cavity of the distal ulna. The objective is to highlight the diagnostic and treatment considerations for this rare variant and emphasize the importance of accurate diagnosis to prevent misdiagnosis and recurrence.

Results

Imaging studies revealed an irregular calcified mass with a pedunculated appearance communicating with the medullary cavity. Surgical resection was successful, and pathological analysis confirmed BPOP diagnosis with characteristic histological features including fibrous tissue, cartilage, bone, and blue bone formations. At 1-year follow-up, the patient showed improved forearm rotation function with no signs of recurrence.

Conclusion

Although BPOP lesions communicating with the medullary cavity are extremely rare, recognition of this atypical presentation is crucial to avoid misdiagnosis as osteochondroma. Comprehensive understanding of BPOP characteristics combined with adequate surgical resection and regular postoperative follow-up are essential for optimal management and prevention of recurrence.
  • Published in:BMC Musculoskeletal Disorders,
  • Study Type:Case Report,
  • Source: 10.1186/s12891-024-07715-4, PMID: 39061015
Scroll to Top