Answer
The tripartite coxal (hip) bone of adults is formed fro three bones which are separate in infants. These are the ilium, ischium and pubis. The ilium is the largest of the three, and it extends from the iliac crest to the center of the acetabulum. . The iliac crest runs from from an anterior ridge ( angle) called the anterior superior spine and continues to a sharp posterior angle , the posterior superior spine. there are also two inferior spines ( anterior and posterior; they are located below the superior spines. The greater sciatic notch of the ilium is located just below the inferior spines . the greater sciatic notch is named after the large sciatic nerve -- the longest spinal nerve-- that passes through the notch and continues down the posterolateral side of the thigh.
The ischium is the inferoposterior side of the coxal bone.. Its heavy body is marked with a prominent spine. Inferior to the spine is a slight indentation which is the lesser sciatic notch. The thick rough ischial tuberosity of the ischium supports the body when we sit. The ramus of the ischium joins the inferior ramus of the pubis anteriorly.
Work Step by Step
The pubis is the most anterior part of the coxal bone, It runs almost horizontally, and provides support for the urinary bladder. Each bone has a superior and an inferior ramus in addition a the body; the bodies of the two bones meet to form the pubis symphysis The pubis and the ischium encircle the obturator foramen
