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;
Squamous part of the frontal bone the supraorbital margins the squamous part projects downward to a level below that of the zygomatic processes. It meets the nasal bone where it presents a rough, uneven serrated notch known as the nasal notch, and this articulates on either side of the middle line with the nasal bone, and laterally with the frontal process of the maxilla and with the lacrimal. This part is sometimes called the nasal part of frontal bone. The term nasion is applied to the middle of the frontonasal suture. From the center of the notch the nasal process projects downward and forward beneath the