Arthroscopic Synovectomy and Removal of Loose Bodies in Synovial Osteochondromatosis of the Knee

Synovial osteochondromatosis is a benign process that most commonly affects the knee joint (70%). It is characterized by proliferative metaplasia of synovial membrane into chondrocytes, resulting in the formation of multiple cartilaginous nodules, which can detach from the synovium to become multiple intra-articular loose bodies. It usually involves the anterior compartment, including infrapatellar fat pad, suprapatellar pouch, and anterior interval, and rarely involves the posterior compartment of the knee. Treatment for synovial osteochondromatosis usually involves surgery, especially in the presence of locking symptoms or decreased range of motion. Arthroscopy has gradually replaced a traditional open approach, resulting in low morbidity, low postoperative pain, better cosmetic results, early recovery of range of motion, short rehabilitation course, and an early return to previous function. In case of involvement of the posterior compartment of the knee joint, arthroscopic access may be difficult. In this Technical Note, the technical details of arthroscopic synovectomy and removal of loose bodies in synovial osteochondromatosis of the knee is described. This arthroscopic technique can deal with the disease, involving both the anterior and posterior compartments of the knee joint.