[A posterior horn syndrome presumably due to direct trauma to the sacral cord: a rare complication of epidural anesthesia].

I report here a case of a posterior horn syndrome presumably due to sacral cord injury during the procedure of epidural anesthesia. A 43-year-old female underwent hysterectomy for myoma uteri. The operation was initially planned to be performed under epidural anesthesia. When a needle was inserted at the level of Th 12/L 1, she felt severe pain in the medial aspect of the left thigh. After the operation under general anesthesia, intolerable pain continued in the buttocks, the medial aspect of the left thigh, and the posterolateral aspect of the left lower leg. Lumbar MR images demonstrated slight disc hernia but no intra- and extramedullary hematomas. Seven weeks after the operation, she was referred to my clinic for neurologic evaluation. Motor functions were intact. Knee jerks on both sides were hyperactive; other tendon reflexes were normal. Plantar reflexes were indifferent. Thermal and pin-prick sensations were lost in the left S1 dermatome, and moderately impaired in the left S2 dermatome. Light touch and vibration sense showed no remarkable changes. Her sensory disturbance could have been caused by a lesion involving the left posterior horn and lateral spinothalamic tract within the S1 segment of the spinal cord.