Computer-Assisted Hip Arthroscopic Surgery for Secondary Femoroacetabular Impingement After Rotational Acetabular Osteotomy Using Capsular Takedown Techniques.

Secondary femoroacetabular impingement (FAI) is a severe complication observed after acetabular osteotomy; however, the diagnostic and treatment strategies of FAI have not been well established, especially with respect to arthroscopic techniques. We here describe hip arthroscopic osteochondroplasty for secondary FAI using computer-assisted techniques. The main features and tips of our technique are preoperative computed tomography (CT)-based surgical planning and the intraoperative capsule takedown method. Computer modeling produces a patient-specific 3-dimensional CT bone model. Subsequently, we identify the impingement point between the acetabulum and the femoral neck using dynamic simulation. The excess bony bumps are resected through computer surgical simulation, and pre- and postoperative 3-dimensional CT bone models are combined to identify the appropriate resection area. For the surgical technique, it is important to detach the capsule to visualize the acetabulum bony excess. Once the resection area has been sufficiently visualized, the bone resection is performed. Finally, the capsule is reattached to the excavated acetabulum, and the delaminated labrum is sewn up with the capsule in a round bale shape.