Neurological Disorders: Cauda Equina Syndrome

Cauda equina syndrome is a neurological disorder resulting from injury or pathology of the cauda-equina structure. Neurologist & neurosurgeons are the specialist doctors who are usually involved in the care of these patients.

This structure is formed by a bunch of spinal nerve roots and rootlets at the lumbosacral area of the spine. In adults the spinal cord ends around the lower border of L1 vertebra usually. The spinal nerve roots that emerge from the spinal cord have to take an exit below the corresponding vertebra. That means many of the lumbar, all sacral and coccygeal spinal roots have to first travel downwards then laterally to reach their corresponding neural foramen (spinal exit). This gives rise to an appearance of a horse tail for these bundle of nerve toots, hence this structure is called as above.

Myriad pathological conditions can damage these structures including;

• Trauma
• Degenerative arthritis
• Spinal stenosis
• Large disc herniation
• Tumors (primary and secondary)
• Inflammatory conditions like Guillain Barre syndrome & CIDP (chronic inflammatory demyelinating polyradiculoneuropathy)
• Infections like spinal meningitis
• Injection of dye for procedures like myelogram (in the past)

Depending upon what cause this syndrome the manifestations can occur rapidly or slowly.

The following manifestations are generally seen;

• Leg muscle weakness
• Numbness
• Loss of sensation in the legs and perianal area
• Tingling sensation (pins & needles)
• Bladder and/or bowel symptoms
• Unsteadiness of gait
• Diminished or absent deep tendon reflexes
• Sexual problems
• Lower back pain with radiating pain to legs (radiculopathy)

The manifestations of cauda equina syndrome are generally asymmetric; means not equally distributed in both the legs. There is a similar condition called as conus medullaris syndrome which results due to damage to the lower end of the spinal cord called as conus medullaris. With this condition manifestations are similar to cauda-equina syndrome however they are more symmetric in nature.

Once this condition is clinically suspected then imaging studies of the spine like CT or MRI is obtained. They are usually done with and without contrast. An EMG/NCS (electromyography and nerve conduction study) and a CT myelogram also may be necessary sometimes.

The treatment of this condition depends upon what caused it, e.g. if a disc prolapse is the cause then it is treated in that line (usually with discectomy). Physical therapy is given if muscle weakness is present. Bowel and/or bladder symptoms are dealt appropriately.