Synovial osteochondromatosis of the hip joint. Etiology, diagnostic investigation and therapy.

Synovial osteochondromatosis (Reichel's syndrome) of the hip joint is an unusual entity that is difficult to diagnose in the initial stages. In the beginning the condition is characterized by recurrent pain in the affected joint with negative radiographic and MR findings. The first stage shows only synovial reaction without loose bodies. In the second stage radiography is negative because of cartilaginous bodies, and even in the third stage radiography is negative in one third of cases although osseous bodies are present. After diagnosis surgery is indicated to prevent damage to the joint. We review the etiology, clinical findings and differential diagnosis especially types of secondary synovial chondromatosis and discuss ultrasound, radiologic, MR and scintigraphic features and laboratory findings. We describe the surgical treatment and postoperative treatment of patients with synovial osteochondromatosis with moderate signs of secondary osteoarthritis.