Sacrotuberous ligament

A ligament connecting the sacrum to the ischial tuberosity of the pelvis.

The sacrotuberous ligament is a fibrous band that extends from the sacrum, specifically the posterior superior aspect, to the ischial tuberosity of the pelvis. It plays a crucial role in stabilizing the pelvis and is an important structure in the context of pelvic anatomy. Its name reflects its connection between the sacral area and the tuberosity found on the ischium, one of the bones that form the hip.

Terminologia Anatomica

ligamentum sacrotuberale

System

Musculoskeletal system

Function

The primary function of the sacrotuberous ligament is to provide support and stability to the pelvis. It helps maintain the integrity of the pelvic structure by connecting the sacrum, which is part of the spine, to the ischial tuberosity, a key point of attachment for various muscles of the hip and thigh. This ligament is particularly important in bearing the weight of the upper body when sitting or standing, contributing to the overall stability of the pelvic girdle. Additionally, the sacrotuberous ligament assists in the movement of the hip joint by influencing the orientation and tension of the surrounding musculature, thus playing an indirect role in locomotion and balance.

Location

The sacrotuberous ligament is located posteriorly in the pelvis. It originates from the dorsal surface of the sacrum, specifically the lower sacral vertebrae and the coccyx. The ligament then extends horizontally and laterally to attach at the ischial tuberosity, which is situated at the inferior part of the pelvis. This positioning allows the ligament to form an essential connection between the axial skeleton (the spine and sacrum) and the appendicular skeleton (the bones of the pelvis and legs). The ligament is situated near important structures such as the sacroiliac joint and is in close proximity to significant nerves and blood vessels in the pelvic region.

Did You Know?

The sacrotuberous ligament contributes to the formation of the greater and lesser sciatic foramina, which are important passageways for nerves and blood vessels.
In women, the sacrotuberous ligament can stretch and loosen during pregnancy, allowing for greater flexibility in the pelvis during childbirth.
It is often involved in conditions like sciatica, where it may contribute to discomfort by affecting the nearby sciatic nerve.