Extensive Case of Primary Synovial Osteochondromatosis of the Shoulder

Abstract

Background: 
 Synovial osteochondromatosis is a rare and benign set of cartilaginous tumors that calcify in the synovial layer of joints. These masses reduce a joint's range of motion and produce chronic low-grade pain. They can destroy local tissues such as muscles, ligaments, and nerves. Diagnosis is often delayed due to the rare nature of the condition and the nonspecific symptoms of pain, reduced range of motion, and swelling. 
 The Case: 
 A 49-year-old male presents with right shoulder pain and stiffness that has progressively decreased his range of motion since his teenage years. Radiographic imaging revealed severe glenohumeral arthritis with large calcified bodies surrounding the glenohumeral joint. Shared decision-making led to an anatomic total shoulder arthroplasty (TSA) with biceps tenodesis. Nineteen independent calcified bodies were removed from the right shoulder. Eight weeks after surgery, the patient was happy with his progression. The patient demonstrated significant improvement in the range of motion of the operative extremity.
 Conclusion: 
 We present this case report to help providers form a complete differential and encourage ordering diagnostic tests that pinpoint the exact condition so referral to appropriate treatment modalities, including surgery, is not delayed.