Objectives: Synovial chondromatosis is an uncommon benign neoplastic process of the synovial membrane of joint. The incidence is of 1:100000, and affects male two to four times more than females, frequently in the third to fifth decades of life. It’s a monoarticular process that involves large joints like hip, elbow, shoulder, and ankle. Knee is the most commonly join affected (65% of cases). It’s characterized by the formation of multiple cartilaginous nodules in the synovial tissue of joints, that often detach and become free bodies. Secondary ossification occurs in 70% - 95% of cases. The main symptoms are swelling of the join, pain, and restriction of movement. Radiology plays a key role for correctly diagnosing. Treatment includes removal of the loose bodies (with or without synovectomy) through an open or arthroscopic approach. Local recurrence is estimated from 3% to 25%. Radiotherapy, Radiosynovectomy and local anesthetic and cortisone injections are also described.
Design: A 40 years old male patient presented a 10 months history of unspecified knee pain in absence of preceding trauma. Physical exam manifested limitation of range of motion, stiffness and joint swelling. US evidenced multiple hyperechoic intrarticular foci. X-ray demonstrated multiple intrarticular calcifications of similar size. Finally a MR was executed, showing a synovial effusion including multiple intrarticular free bodies in which cortical and medullary bone were recognized, suggestive of osteochondromatosis. Differential diagnosis initially included Condrocalcinosis and Pigmented Villonodular Synovitis.
Conservative management based on NSAID, ROM exercises and electrotherapy, was indicated to induce symptomatic improvement, waiting for definitive surgical treatment, that was finally performed with good results.
Giuseppe De Bernardo– Resident in Physical Medicine and Rehabilitation, Ramón y Cajal Hospital - Madrid
Carolina De Miguel Benadiba– Specialist in Physical Medicine and Rehabilitation, Ramón y Cajal Hospital
Adrian José Maldonado Viloria– Resident in Physical Medicine and Rehabilitation, Hospital Ramon y Cajal