Cauda Equina Syndrome: An Overview

The name arises from the Latin words “Cauda” meaning “tail” and “Equina” meaning "horse.” It is descriptive of the nerves in the lower most spinal region where the nerve fibers branch out to look like a horse tail. This disorder occurs due to the compression of these nerves at the horse tail region due to various reasons. Compression most commonly occurs in the lower lumbar region, particularly due to a large lumbar disc herniation at the L4–L5 or L5–S1 level.

These bundles of nerves are responsible for sensation and physical functions in certain areas of the body, and the damage can result in numbness, altered leg sensations, lower back pain, and issues with bowel/bladder emptying. It might also lead to failure of muscular structures responsible for bladder control and cause abnormal sensation in the legs.

Common Causes of Compression

Nerve compression can result from trauma, lower back injuries, infections surrounding the spine or brain (meningitis), slip disc, tumors, or even as a surgical complication. Slip disc is the most common cause, where the jelly-like soft tissue disc protrudes or bulges into the bony part.

Trauma from improperly lifting heavy weights can increase the risk of nerve compression injury leading to cauda equina. When the fluid surrounding the brain and spinal cord gets infected with pus, the fluid accumulates and presses on the lower spine region to cause nerve compression.

Symptoms

It is a rare condition and diagnosing it at the right time becomes crucial for improving symptoms early and preventing long-term complications. However, the symptoms may be overlooked for other conditions, and treatment delays may cause irreparable damage or permanent loss of sensation.

Cauda equina usually arises as low back pain, and as the condition progresses, patients experience symptoms of numbness or weakness in one or both of their legs (single or bilateral sciatica), bladder control problems, unable to control defecation, and numbness in the perineum (an area between genitalia and anus).

In addition to urinary symptoms, some patients also experience inability to walk or stand due to lack of sensation while some patients may be able to walk even though there is numbness. Sexual dysfunction symptoms such as erectile dysfunction and altered sexual sensations are caused due to damaged nerve fibers associated with these functions.

Sometimes, changes in bladder function can lead to incomplete bladder emptying and this is confirmed when the retention of urine in the bladder measures more than 200 mL when tested. Getting an MRI is appropriate when cauda equina is suspected to avoid irreversible complications at an early stage.

Treatment and Outcomes

The key factor in treating CES is identifying the condition at the right time. CES should be treated like an emergency condition, and one should visit the doctor immediately if there is altered sensation or numbness near the genital area and legs including symptoms like lower back pain and urination issues.

Surgery is usually performed to decompress the impacted nerves to re-establish blood supply, function, and improving sensation. Post recovery from surgery, physical therapy and Kegel’s exercises might be recommended to strengthen the muscles and resume normal functions gradually. Time taken for healing or reversal of damage varies from person to person and the treatment alone does not guarantee full recovery for all patients. Some people may continue to have issues lifelong even after decompression surgery and may need psychotherapy to cope with any associated stress or depression.

References

1.       Aduri, T. T., Mishra, P. K., Verma, V., Jain, N., & Prasad, S. S. (2026). Cauda equina syndrome: A narrative review exploring the pathophysiology, clinical spectrum, diagnostic strategies, and time-critical management. Cureus, 18(5), e108930. https://doi.org/10.7759/cureus.108930

2.       Cleveland Clinic. (n.d.). Cauda equina syndrome. Cleveland Clinic. Retrieved June 5, 2026, from https://my.clevelandclinic.org/health/diseases/22132-cauda-equina-syndrome

3.       Lavy, C., Marks, P., Dangas, K., & Todd, N. (2022). Cauda equina syndrome—A practical guide to definition and classification. European Journal of Orthopaedic Surgery & Traumatology, 32(2), 165–169. https://doi.org/10.1007/s00264-021-05273-1

4.       McCarthy, M. J. H., Aylott, C. E. W., Grevitt, M. P., & Hegarty, J. (2022). Cauda equina syndrome: A comprehensive review. American Journal of Obstetrics and Gynecology, 226(4), 555–564. https://doi.org/10.1016/j.ajog.2021.08.003

5.       Todd, N. V., Dickson, R. A., & Standards of Care Committee of the Society of British Neurological Surgeons. (2022). Cauda equina syndrome: The current incidence, diagnosis, management, and outcome in the United Kingdom. The Lancet Regional Health – Europe, 21, 100504. https://doi.org/10.1016/j.lanepe.2022.100504

6.       Wilson-MacDonald, J., Balasubramanian, K., & Fairbank, J. (2024). Cauda equina syndrome: A comprehensive review. Hospital Medicine, 84(1), 22–29. https://doi.org/10.12968/hmed.2023.0012

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