A 52-Year-Old Male with Upper Arm Pain and Swelling of No Known Origin

Differential Diagnosis

• Chondrosarcoma
• Osteoarthritis
• Osteochondritis dissecans
• Osteochondromatosis of the synovial sheath of the biceps tendon
• Synovial chondrosarcoma

Diagnosis

The x-ray shows multiple round or oval calcific/ossific bodies along the anterior surface of the humerus in the region of the bicipital grove and the biceps tendon. Also, single oval ossific body in the axillary recess of the shoulder.

This patient was diagnosed with osteochondromatosis of the synovial sheath of the biceps tendon and the axillary recess of the shoulder joint. Synovial osteochondromatosis is a proliferative disorder of the synovial lining of the joint, bursa, and tendon sheaths.

Learnings/What to Look for

• This diagnosis is characterized by synovial membrane proliferation and metaplasia, with development of multiple cartilaginous and osteocartilagenous bodies in the joint space, synovial bursa, or the tendon sheath
• Osteochondromatosis presents with painful swelling of the upper arm and a palpable tender mass in the region of the biceps tendon
• Radiographic findings include presence of multiple round or oval osteochondral bodies in the region of bicipital groove and the biceps tendon. There may or may not be accompanying shoulder joint osteochondromatosis with restricted joint movements

Pearls for Urgent Care Management and Considerations for Transfer

• Treatment is usually surgical, either open or arthroscopic with excision of the osteochondral bodies with or without resection of synovium. Recurrence is not uncommon

Acknowledgment: Image and case presented by Experity Teleradiology (www.experityhealth.com/teleradiology).