A 60-year-old male with a known history of L4-L5 degenerative spondylolisthesis presents to the emergency department with acute onset bilateral leg weakness, saddle anesthesia, and urinary retention. Which of the following is the most appropriate immediate management step?

Explanation

The patient's symptoms (acute onset bilateral leg weakness, saddle anesthesia, urinary retention) are classic signs of cauda equina syndrome, a surgical emergency. While degenerative spondylolisthesis is the underlying condition, the acute neurological deficit necessitates urgent evaluation to confirm the diagnosis and identify the level of compression. An urgent MRI is the gold standard for this. NSAIDs, bed rest, and physical therapy are conservative measures for stable spondylolisthesis without acute neurological compromise. Elective surgery is not appropriate for an acute emergency; urgent decompression would be considered after MRI confirmation.