Motor evoked potential study suggesting L5 radiculopathy caused by XXXX disc herniation: case report.

@entity1 @entity6356 @entity425 @entity158
A 38-year-old male was referred because of @entity158 in the left 5th lumbar (L5) root territory. Physical examination found moderate @entity425 in the left extensor hallucis longus (EHL) and the left tibialis anterior muscles. Magnetic resonance imaging found no stenotic lesion between L4-L5, but disc herniation was observed on the left between L1-L2. An L5 nerve root block provided temporary relief of the @entity158 but the left foot @entity425 was exacerbated. Therefore, surgery was performed. Partial laminectomy and left herniotomy were performed at L1-L2, L2-L3, and L3-L4 with motor evoked potential (MEP) monitoring. The MEP amplitude of the left EHL muscle increased immediately after L1-L2 herniotomy. The MEP amplitude of the right EHL muscle also increased after both laminectomy and herniotomy. The postoperative course was uneventful. The left leg @entity158 and @entity425 disappeared. The @entity1 has been doing fine without recurrence for 12 months. Since the MEP of both left and right EHL muscles improved after the @entity6356 herniotomy, circulatory insufficiency might have caused the L5 symptoms. Monitoring of the MEP during the surgery was useful for confirming the responsible lesion and also for predicting the postoperative course.
