Cauda equina syndrome due to lumbar disc herniation and ossification of the yellow ligament

Background: Patients with lumbar disc herniation at a level with significant stenosis due to ossification of the yellow ligament (OYL) may rarely present with rapid neurological deterioration warranting emergent surgery. Case Description: A 40-year-old female developed an acute cauda equina syndrome (CES) attributed to an acute lumbar disc herniation and to marked canal stenosis due to OYL. As the patient underwent a 9 h delayed removal of the ossified ligament and discectomy, she sustained only minimal recovery. Conclusion: Patients diagnosed with acute lumbar disc herniation and severe stenosis due to OYL who present with acute CES warrant emergent surgical decompression to avoid permanent postoperative neurological sequelae.