Remaining Loose Bodies after Arthroscopic Surgery Including Extensive Capsulectomy for Synovial Chondromatosis of the Hip

Background: The purpose of our study was to evaluate the usefulness of hip arthroscopy including extensive capsulectomy for synovial chondromatosis of the hip. Methods: From 2008 to 2016, 13 patients with synovial chondromatosis of the hip were treated with arthroscopic removal of loose bodies and synovectomy using three arthroscopic portals. An extensive capsulectomy was performed to allow the remaining loose bodies to be out of the extracapsular space, and the excised capsule was not repaired. All patients were assessed by clinical scores and the radiographs were reviewed to determine whether the remaining loose bodies disappeared at the last follow-up. Results: Eight men and two women were followed up for a minimum of 1 year (mean, 3.8 years; range, 1 to 6.8 years) after hip arthroscopy. Clinical outcomes such as modified Harris hip score, University of California Los Angeles score, and Western Ontario and McMaster Universities Osteoarthritis Index score improved at the last follow-up. Although seven hips had remaining loose bodies after arthroscopic surgery, the remaining loose bodies disappeared in five hips (71.4%) at the last follow-up. Conclusions: Arthroscopic surgery was useful to treat synovial chondromatosis of the hip. In spite of limited removal of loose bodies, arthroscopic procedures including extensive capsulectomy could be effective for the treatment of synovial chondromatosis of the hip.