A patient presents with bilateral leg weakness, perineal numbness, and urinary retention. What condition should be suspected until proven otherwise?

• A. Cauda equina syndrome
• B. Herniated disk at L5-S1
• C. Spinal stenosis
• D. Lumbosacral strain

Answer: (A)

The presentation of bilateral leg weakness, perineal numbness, and urinary retention strongly suggests cauda equina syndrome. This condition occurs when there is compression of the cauda equina, a bundle of spinal nerves located at the lower end of the spinal cord. The combination of neurological symptoms such as weakness in the legs and sensory changes in the perineal area, along with urinary dysfunction, are classic indicators of this syndrome.

Cauda equina syndrome is a surgical emergency requiring prompt diagnosis and intervention to prevent permanent damage. The symptoms arise because the nerves that control lower extremity motor function and bladder sensation are affected by the compression, which can be caused by a variety of conditions, including herniated discs, tumors, or trauma to the spine.

In contrast, the other listed conditions may present with similar symptoms but typically do not include the triad of symptoms as prominently as cauda equina syndrome. For instance, while a herniated disk at the L5-S1 level may cause leg weakness and possibly sensory changes, it doesn't always result in urinary retention, which is a key symptom of cauda equina involvement. Similarly, spinal stenosis and lumbosacral strain can cause leg pain and weakness, but they do not