ANAT30007 Lecture Notes - Lecture 23: Weight-Bearing, Sciatic Nerve, Trabecula
23 Jul 2018
School
Department
Course
Professor
Document Summary
Between inferior articular (intero-laterally oriented) facet of l5 and superior articular facet of s1 (hold l5 in place to stop anterior tilting) Form closure between 2 iliac blades which come together. Interosseus ligament makes it fibrous at posterior side (needed for weight bearing) Sacrotuberous turns greater sciatic notch into a foramen where sciatic nerve, piriformus muscle travels. Lesser sciatic foramen has the obturator internus muscle (from origin of obturator membrane in the pelvis and then becomes a rotator cuff) Tendency of pelvis is to tilt downward in rotational movement at axis of s2 anteriorly (nutation) Nutation makes the hole in pelvis smaller (inlet). Trabeculae in femur allow for dissipation of forces from both arches. Wider at top end and narrow at bottom so holds. Arch holds keystone up by tightening interosseus ligaments. 2 articular faces with hyaline cartilage and fibrocartilaginous disc in between. Likely to have several sides fractured and only with direct trauma.
