Surgical Anatomy of Bernese Periacetabular Osteotomy Modified Approach. A Cadaveric Study

Introduction:The Bernese periacetabular osteotomy (PAO) is one of the most widely used surgical techniques in hip dysplasia.Several modifications in the approach have been described in the literature.The iliocapsularis muscle is a valuable landmark in the PAO approach, owing to its constant presentation and being an element that may help protect neurovascular structures.Objective: This study aims to describe this surgical technique through an anatomical-cadaveric study performing a split incision of the Iliocapsularis muscle and show the clinical results regarding the care of the motor branch of the femoral nerve and the lateral femoral circumflex artery. Surgical technique:One cadaveric specimen was used for the cadaveric dissection.An oblique inguinal incision is performed.An anterior superior iliac spine osteotomy keeping the sartorius insertion intact is performed.The rectus femoris muscle is exposed, keeping its direct and reflex insertions intact.The iliocapsularis is dissected into two halves: a lateral one that remains in its position and a medial one that is rejected medially which protects the motor branch of the femoral nerve).Subsequent osteotomies described according to the original technique are carried out.Methods: Prospective Cohort of patients with hip dysplasia operated by the same surgeon using the current technique between June 2016 and July 2022.A directed physical examination was performed to evaluate the motor branch of the femoral nerve on the first postoperative day, and then during the follow-up period.Results: 88 Bernese periacetabular osteotomies, no patients were excluded.63.4% females, 27.7 (15-49) years old, 47.5 months (3-75) follow-up.One femoral nerve neuropraxia was secondary to a hematoma, which resolved completely.One self-limited paresthesia was detected in the territory of the lateral femoral cutaneous nerve. Conclusion:Iliocapsularis split dissection provides adequate protection for the motor branch of the femoral nerve and the lateral femoral circumflex artery.