Editorial Commentary: Revision Hip Arthroscopy in Patients With Borderline Dysplasia Has a Role: Indications Are Narrow Versus Periacetabular Osteotomy.

Hip arthroscopy (HA) is preferred for surgical management of femoroacetabular impingement syndrome, whereas periacetabular osteotomy (PAO) is the gold standard for frank developmental hip dysplasia in young adults. Borderline hip dysplasia (BHD) is a conundrum, with data supporting the use of either or both, not to mention that BHD is defined by varying lateral center-edge angle thresholds between 18° and 25° or 20° and 25° and features generalized ligamentous laxity and variations in acetabular and femoral version. That said, HA for BDH has been shown to have 10-year survivorship of 82%. In a revision situation after HA in patients with BHD, PAO seems a logical next step, but HA may be indicated under narrow indications. From a technical standpoint, capsular preservation, labral function restoration, and avoiding acetabular rim over-resection are key points when performing HA in BHD. Most important, particularly in the revision setting, is to determine the root cause of failure. Primarily, instability-driven symptoms are an indication for PAO.