Hip arthroscopy for the treatment of synovial osteochondromatosis

Synovial osteochondromatosis is a benign condition in which pain and functional restriction of the hip are seen because of the numerous intra-articular osteochondral loose bodies produced by a metaplasia of the synovium. Recurrence generally increases morbidity but may also lead to malignant transformation. Recurrence rates reported in the literature after open surgical treatment reach 22%.
A recently published study in the American journal Arthroscopy set out to measure the rate of recurrence of synovial osteochondromatosis after hip arthroscopy, and to identify the factors predisposing to recurrence. The authors of this study carried out a search of three electronic databases, Embase, MedLine and PubMed, to find relevant publications on the arthroscopic treatment of synovial osteochondromatosis. In all they found 2500 studies, of which only 14 met the criteria for inclusion in the study. The result of this study was that recurrence after hip arthroscopy reached a rate of 7.1%, while the rate of minor complications, such as neurapraxia of the perineum and the leg, was about 1%. The authors concluded that arthroscopic removal of the osteochondral loose bodies with simultaneous synovectomy in synovial osteochondromatosis of the hip is a safe and effective technique, with a mean recurrence rate of 7.1%.
In a recent presentation at an orthopaedic congress, Alexandros Tzaveas described the management of three of his own patients with synovial osteochondromatosis. These patients had primary synovial osteochondromatosis and underwent hip arthroscopy. Two of the patients had the disease at an intermediate stage (Milgram stage 2), while the third had it at an advanced stage (Milgram stage 3). The technical difficulties during the arthroscopy and the outcome of the procedure at a maximum follow-up of 36 months were described.
In all the patients an attempt was made to remove as many loose bodies as possible, together with a wide synovectomy. The patients had loose bodies in both the central and the peripheral compartment. The presentation of the paper described all the technical difficulties of hip arthroscopy in such patients, such as the difficulty of entering the peripheral compartment, the difficulty of visualising the peripheral compartment when it is full of loose bodies, the inability to remove all the loose bodies, the inability to reach the posterior peripheral compartment and the inability to perform a synovectomy over the whole extent of the capsule. Nevertheless, all the patients showed great improvement both in range of motion and in pain levels.
The conclusion of the presentation was that hip arthroscopy is a good option for the management of this condition and offers all the advantages of a minimally invasive technique, with a very short hospital stay and very low morbidity.