Monday, December 5, 2011

Sacral Plexus

The sacral plexus is a network of nerves composed of lumbosacral trunk and the sacral nerve. The lumbosacral trunk (parts of L4 and L5) and the anterior branches of the sacral nerve S1 – S3 join on the anterior surface of the piriform muscle (on the back of the pelvis) to form the sacral plexus. Direct branches extend from the plexus to the muscles of the pelvic region, namely, to the piriform muscle, the gemellus muscles, the internal obturator muscle, and the quadrate muscle of thigh.