Muscle, Iliococcygeus (M. Iliococcygeus)

The muscles, called in Russian iliac or intergluteal, connect the gluteus maximus and minimus muscles and suspend the trochanter of the femur to the sacrum.

The shape and function of the iliacus muscles are very distinctive, and in a newborn they are almost indistinguishable by eye. They represent only a slight thickening of the lower part of the lateral abdominal wall. As the muscles develop and the pelvis lowers, the umbilical ring moves closer to the womb, the segments of the coccyx and the greater ischium penetrate into the bone bed formed by the lily of the attachment muscles and the ischial tuberosities. The lower end of the diaphysis of each of them is strengthened in the coccyx, in close proximity to the perineum. From the medial belly of the pelvic diaphragm, the muscles take on the appearance of a kind of thin cone.

Due to the fact that the tops of the muscles are directly connected to the ligament, and the bases are firmly connected to the pelvis, they contract and lift the pelvis together.

Together with the levator psoas muscle, they constitute the three main muscles of the pelvic floor. Inside the abdominal cavity, each muscle is embedded between the wall of the lower rectum and the subcutaneous tissue. In adults, they occupy the spaces between the sacrum and the seat.