Ischium Ischium The ischium () forms the lower and back part of the hip bone ("os coxae"). Situated below the ilium and behind the pubis, it is one of these three bones whose fusion creates the hip. The superior portion of this bone forms approximately one third of the acetabulum. The ischium is made up of three parts–the body, the superior ramus and the inferior ramus. The body contains a prominent spine, which serves as the origin for the superior gemellus muscle. The indentation inferior to the spine is the lesser sciatic notch. Continuing down the posterior side, the ischial tuberosity
Sciatic nerve block Sciatic nerve block A sciatic nerve block is a nerve block that uses local anesthetic to achieve analgesia in the leg. The block works by affecting the sciatic nerve and is used for surgeries at or below the knee. The sciatic nerve is located in the gluteus maximus muscle, where the block is performed. The sciatic nerve can be blocked at different locations. At the popliteal fossa, the sciatic nerve divides into its two branches: The tibial and the common peroneal nerve. If surgery is performed on the ankle, achilles tendon or foot a popliteal block can be performed, affecting