L1 radiculopathy mimicking meralgia paresthetica: a case report.

L1 radiculopathy is very rare and difficult to diagnose with needle electromyography. A patient presented with pain and hypesthesia on the anterolateral aspect of the left thigh. Nerve conduction studies and needle electromyography were normal, except for the quadratus lumborum and iliopsoas muscles, which showed abnormal spontaneous activity and polyphasic motor unit potentials with reduced recruitment patterns. Magnetic resonance imaging of the lumbar spine showed disc extrusion of the L1-2 intervertebral space with upward migration. This case demonstrates the usefulness of examination of the quadratus lumborum in the diagnosis of L1 radiculopathy.