Ischium jumping hurdles, basketball, and martial arts. These fractures occur at tubercles (bony projections that lack secondary ossification centers). Avulsion fractures occur where muscles are attached: anterior superior and inferior iliac spines, ischial tuberosities, and ischiopubic rami. A small part of bone with a piece of a tendon or ligament attached is avulsed (torn away). Ischial bursitis (also known as "weaver's bottom") is inflammation of the synovial bursa located between the gluteus maximus muscle and the ischial tuberosity, and is usually caused by prolonged sitting on a hard surface. Adoption of "ischium" into English-language medical literature dates back to c. 1640;
Sciatic nerve incidence of 1.7% to 7.6% following revision. Following the procedure, in rare cases, a screw, broken piece of trochanteric wire, fragment of methyl methacrylate bone cement, or of a Burch-Schneider antiprofusio cage can impinge on the nerve; this can cause sciatic nerve palsy which may resolve after the fragment is removed and the nerve freed. The nerve can be surrounded in oxidized regenerated cellulose to prevent further scarring. Sciatic nerve palsy can also result from severe spinal stenosis following the procedure, which can be addressed by spinal decompression surgery. It is unclear if inversion therapy is able to decompress the