Cauda Equina Syndrome

Cauda Equina Syndrome Overview

The spinal cord extends from the brain down through the spinal canal inside the vertebral column. The spinal cord is surrounded by dural sacs, which are extensions of the brain-covering membranes. The brain-covering membranes are dura matter; arachnoid, which contains cerebrospinal fluid; and pia matter. Nerves that branch off of the spinal cord (also called nerve roots) are an extension of the spinal cord and are responsible for sending signals to and from the muscles and other structures throughout the body. These signals allow the brain to interpret information from the body including pain, touch, and sense of position. Outgoing signals allow the brain to control actions of the organs and muscle movements.

The spinal cord ends near the first lumbar vertebra in the lower back, forming the conus medullaris. The fibrous extension of the spinal cord is the filum terminale. The bundle of nerve roots below the conus medullaris is named the cauda equina (see Multimedia File 1). 

Compression or inflammation of the nerves roots can cause symptoms of pain, altered reflexes, decreased strength, and decreased sensation. Although these symptoms can become severe, and in some cases disabling, most are self-limiting and respond to conservative care.