What is a cauda equina problem?
Cauda equina syndrome is a serious neurologic condition. There is a sudden loss of function of the nerve roots of the spinal canal below the conus (end of the spinal cord). The spinal cord travels down the spine inside the spinal canal. The canal is a circular opening formed by the vertebral bodies. In most people, the spinal cord ends around the first or second lumbar vertebra. After that, there is a mass of nerves called the cauda equina. Translated literally, this means horse tail. As part of the cauda equina, nerve roots branch off from the spinal cord from L1-5 and S1-5. Anything that presses on the cauda equina can disturb the nerves. The most common problem leading to a cauda equina lesion is a central disc prolapse. This means the disc located between two vertebrae (in this case between L4 and L5) pushes straight back and presses on the spinal cord. Weakness of the legs from pressure on the nerve roots supplying the leg muscles is a common first sign of a cauda equina syndrome. If the compressive force on the spinal cord or cauda equina is severe enough, the person can even become paralyzed. Another sign of cauda equina compression is poor bladder function. The patient may not feel the stream of urine when going to the bathroom. There may be decreased rectal tone, saddle anesthesia, and sexual dysfunction. Saddle anesthesia refers to numbness in the area of the groin that would be in contact with a saddle. This is a sign of serious nerve impairment. Some patients with a cauda equina lesion have no pain and can still walk. Others are in a wheelchair and cannot function. The diagnosis is usually made based on clinical presentation and confirmed by an MRI or CT scan. Immediate surgery to decompress the disc is usually advised. Whether or not the patient can have a decompressive discectomy (disc removal) depends on the underlying cause of the compression and the patient's general health.