Sudden bilateral foot drop without cauda equina syndrome: An unusual presentation of lumbar disc prolapse

Bilateral acute foot drop is reported in a 59 year-old healthy male. He presented with a 2 days history of severe backache, sciatica and a history of sudden bilateral ankle weakness that progressed to bilateral foot drop. Investigations revealed a large central disc prolapse at L4/L5 with significant canal stenosis. Following surgery the patient had progressive improvement.Compression of the cauda equina is an uncommon presentation of lumbar disc (2). Rarely, lumbar disc herniation may produce bilateral foot drop. Acute unilateral foot drop has been well described in the literature (3). We report a rare case of a bilateral sudden foot drop, due to an acute central disc prolapse at L4/L5 level, without cauda equina syndrome which has not been reported previously in the literature.