Sacral plexus

A network of nerves located in the lower back, crucial for innervating the pelvis and lower limbs.

The sacral plexus is a major network of nerves situated within the pelvic region, formed from the ventral rami of the first four sacral spinal nerves (S1-S4) and a portion of the lumbar plexus via the lumbosacral trunk. It primarily innervates the lower limbs and pelvic organs, providing motor and sensory functions critical for day-to-day activities.

Terminologia Anatomica

plexus sacralis

System

Nervous system

Function

The sacral plexus plays a pivotal role in mediating the movement and sensation of the lower body. It branches into several important nerves, including the sciatic nerve, which is the largest nerve in the body and supplies the posterior aspect of the leg and foot. Other branches innervate various muscles, including those responsible for hip extension, knee flexion, and foot movements. Additionally, the sacral plexus is vital for providing sensory innervation to the skin of the buttocks, the perineum, and parts of the legs, allowing for the perception of touch, pain, and temperature. Its influence extends to the pelvic organs, enabling functions such as bladder control and reproductive processes.

Location

The sacral plexus is located in the posterior pelvis, justo above the sacrum. It lies behind the pelvic viscera and is positioned anterior to the piriformis muscle. The plexus forms within the bony framework of the pelvic cavity, and its branches emerge to travel down toward the gluteal region, thighs, and legs. Its structure can be visualized as a dense network of nerves that emanate from the sacral region, following a path alongside the bones and muscles of the lower body.

Did You Know?

The sciatic nerve, a major branch of the sacral plexus, is responsible for carrying signals from the spinal cord to the leg and is often referred to as the longest nerve in the body.
Disorders affecting the sacral plexus can lead to significant mobility issues and pain, often impacting daily activities.
Sacroiliac joint dysfunction can sometimes mimic sacral plexus-related issues, leading to diagnostic challenges.