Pipkin骨折.ppt

Hip Dislocations and Femoral Head Fractures John T. Gorczyca, MD University of Rochester Medical Center Created March 2004; Revised January 2006 Introduction Hip dislocations caused by significant force: Association with other fractures Damage to vascular supply to femoral head Thus, high chance of complications Anatomy:Hip Joint Ball and socket joint. Femoral head: slightly asymmetric, forms 2/3 sphere. Acetabulum: inverted “U” shaped articular surface. Ligamentum teres, with artery to femoral head, passes through middle of inverted “U”. Joint Contact Area Throughout ROM: 40% of femoral head is in contact with acetabular articular cartilage. 10% of femoral head is in contact with labrum. Acetabular Labrum Strong fibrous ring Increases femoral head coverage Contributes to hip joint stability Hip Joint Capsule Extends from intertrochanteric ridge of proximal femur to bony perimeter of acetabulum Has several thick bands of fibrous tissue Iliofemoral ligament Upside-down “Y” Blocks hip extension Allows muscle relaxation with standing Femoral Neck Anteversion Averages 70 in Caucasian males. Slightly higher in females. Oriental males and females have been noted to have anteversion of 140 and 160 respectively. Blood Supply to Femoral Head Artery of Ligamentum Teres Most important in children. Its contribution decreases with age, and is probably insignificant in elderly patients. Blood Supply to Femoral Head 2. Ascending Cervical Branches Arise from ring at base of neck. Ring is formed by branches of medial and lateral circumflex femoral arteries. Penetrate capsule near its femoral attachment and ascend along neck. Perforate bone just distal to articular cartilage. Highly susceptible to injury with hip dislocation. Sciatic Nerve Composed from roots of L4 to S3. Peroneal and tibial components differentiate early, sometimes as proximal as in pelvis. Passes posterior to posterior wall of acetabulum. Generally passes inferior to piriformis muscle, but occasionally