Arthroscopic surgery for synovial chondroma of the subacromial bursa with non-traumatic shoulder subluxation complications: Two case reports

BACKGROUND: Synovial chondromatosis is a disease originating from the synovium and characterized by the presence of metaplastic cartilaginous nodules in synovial cavities. The exact prevalence of synovial chondromatosis remains unknown, and the involvement of the shoulder joint is very rare. Synovial chondromatosis accompanied by subluxation of the humeral head without a history of trauma is rarely encountered, and to our knowledge, no published reports describe this condition. CASE SUMMARY: We present two cases of synovial chondromatosis in the shoulder joint, accompanied by subluxation of the humeral head, in two arthroscopically managed adult patients. We performed arthroscopic labrum fixation and removal of the loose body from the shoulder joint. To identify primary and secondary categories, pathological analysis was arranged. Clinical and radiographic evaluations at the 1-mo follow-up were satisfactory. CONCLUSION: The biomechanical function of the shoulder joint requires attention, especially following the detection of loose bodies, as observed with synovial chondroma occurring in rare sites. Arthroscopic management is successful in patients with synovial chondromatosis combined with shoulder subluxation.