Primary synovial chondromatosis of the shoulder

Aim: To demonstrate the various patterns of primary synovial chondromatosis (PSC) around the shoulder and to discuss a therapeutic algorithm. Method: In this retrospective study, 6 patients with histologically proven PSC were operated on. The diagnosis was based on clinical examination, plain X-rays, ultrasonography and MRI in 5/6 patients. Also, a histological examination was done in all cases. According to the localisation of the disease, surgery was done by endoscopy alone, endoscopy together with open surgery or direct open surgery. Results: In one case each, we saw an isolated disease of the subacromial bursa or the gleno-humeral joint. in two cases, we found an intraarticular affection together with the biceps tendon sheath. The other two patients showed a massive periarticular deposition of loose bodies together with a defect of the rotator cuff. All patients with intraarticular disease (5/6) showed different stages of chondromalacia. In 5 of 6 patients all bodies could be removed at surgery. At follow-up after 36 months the patients subjectively rated the result as satisfactory to excellent. In the patients with total removal of the bodies, no recurrences were seen on plain X-ray or ultrasonography. Conclusion: PSC around the shoulder appears with a variable pattern. According to the possible late complications described in the literature (i.e., secondary osteoarthritis, involvement of the rotator cuff and secondary malignant transformation), we find operative treatment justified. Surgery addressing removal of loose bodies and partial synovectomy allows good results. The operative approach (endoscopy or open surgery) is related to the localisation and severity of the condition.