Hip arthroscopy for challenging deformities: global pincer femoroacetabular impingement.

Pincer femoroacetabular impingement occurs in focal or global forms, the latter having more generalized and typically more extreme acetabular overcoverage. Severe global deformities are often treated with open surgical dislocation of the hip. Arthroscopic technical challenges relate to difficulties with hip distraction; central-compartment access; and instrument navigation, acetabuloplasty, and chondrolabral surgery of the posterior acetabulum. Techniques addressing these challenges are introduced permitting dual-portal hip arthroscopy with central-compartment access, subtotal acetabuloplasty, and circumferential chondrolabral surgery. The modified midanterior portal in combination with a zone-specific sequence of acetabular rim reduction monitored with fluoroscopic templating enables precision subtotal acetabuloplasty. Guidelines for acetabular rim reduction include the following suggested radiographic endpoints: postoperative center-edge angle of 35°, a neutral posterior wall sign, and an anterior margin ratio of 0.5. Arthroscopic zone-specific chondrophobic rim preparation and circumferential labral reparative and reconstructive techniques and tools permit the arthroscopic treatment of these challenging deformities.