Cauda equina syndrome is a relatively uncommon condition typically associated 
with a large, space-occupying lesion within the canal of the lumbosacral spine. 
The syndrome is characterized by varying patterns of low back pain, sciatica, 
lower extremity sensorimotor loss, and bowel and bladder dysfunction. The 
pathophysiology remains unclear but may be related to damage to the nerve roots 
composing the cauda equina from direct mechanical compression and venous 
congestion or ischemia. Early diagnosis is often challenging because the initial 
signs and symptoms frequently are subtle. Classically, the full-blown syndrome 
includes urinary retention, saddle anesthesia of the perineum, bilateral lower 
extremity pain, numbness, and weakness. Decreased rectal tone may be a 
relatively late finding. Early signs and symptoms of a developing postoperative 
cauda equina syndrome are often attributed to common postoperative findings. 
Therefore, a high index of suspicion is necessary in the postoperative spine 
patient with back and/or leg pain refractory to analgesia, especially in the 
setting of urinary retention. Regardless of the setting, when cauda equina 
syndrome is diagnosed, the treatment is urgent surgical decompression of the 
spinal canal.