Three-Dimensional Navigation (O-arm) for Minimally Invasive Shelf Acetabuloplasty.

Hip dysplasia is an important cause of osteoarthritis in young adults. For these patients, conservative treatment is an interesting alternative to arthroplasty. The current literature suggests better clinical and functional outcomes when shelf acetabuloplasty is performed for a moderate joint pinch (<50%) associated with an important external coverage defect of the acetabular cup (<25°). Compared with open surgical procedures, minimally invasive surgical techniques or arthroscopy tend to reduce morbidity. To date, the major intraoperative difficulty remains the positioning of the graft. This Technical Note aims to outline a minimally invasive shelf acetabuloplasty, with optimization of the position of the autologous iliac crest bone graft using 3-dimensional navigation.