Anteverting Periacetabular Osteotomy for Acetabular Retroversion

Overview Introduction The periacetabular osteotomy procedure reorients a retroverted acetabulum into a more anatomically appropriate position. Step 1: Evaluation of Acetabular Retroversion Evaluate acetabular retroversion on the basis of a combination of radiographic signs. Step 2: Patient Positioning and Skin Incision After draping and sterile preparation with the patient in a supine position, make an incision following the skin lines of the inguinal fold. Step 3: Exposure of the Deep Muscle Layers and the Pelvic Brim Detach the abdominal wall muscles from the anterior iliac crest and detach the sartorius muscle and the inguinal ligament to expose the iliac fossa and the pelvic brim. Step 4: Surgical Dissection for Preparation of the Ischial Osteotomy Detach the iliocapsularis muscle and mobilize it medially to allow access to the infra-articular space and palpation of the ischial bone. Step 5: Incomplete, Partial Ischial Osteotomy Introduce a curved chisel with a crescent-shaped tip into the infra-articular space in order to perform the osteotomy of the ischial bone. Step 6: Osteotomy of the Superior Pubic Ramus Place subperiosteal blunt retractors around the superior pubic ramus to ensure safe and complete pubic bone osteotomy. Step 7: Supra-Acetabular and Retroacetabular Osteotomy Start the supra-acetabular horizontal osteotomy at the anterior superior iliac spine and end it 2 cm lateral to the pelvic brim, where the osteotomy is angled 100° distally. Step 8: Mobilization of the Acetabular Fragment With the help of a spreader and a 4.5-mm threaded Schanz pin, free and mobilize the acetabular fragment. Step 9: Reorientation of the Acetabular Fragment Perform internal rotation of the acetabular fragment with the help of the threaded Schanz pin. Step 10: Improvement of Anterior Head-Neck Offset (Femoral Neck Osteoplasty) Anterior capsulotomy and improvement of anterior head-neck offset is recommended when internal rotation is <30°. Step 11: Anteroposterior Pelvic Radiograph Following Periacetabular Osteotomy Ideally, a postoperative radiograph should show negative crossover and posterior wall signs while the ischial spine sign typically remains positive. Results The long-term results of the periacetabular osteotomy in a series of twenty-two patients (twenty-nine hips) with symptomatic acetabular retroversion were evaluated after a mean duration of follow-up of eleven years (range, nine to twelve years). Indications Contraindications Pitfalls & Challenges