41 patients (lumbar canal stenosis: 21, lumbar disc herniation: 18, others: 4) with lumbosacral radicular symptoms were examined for skin temperature before and after the nerve root infiltration (L5: 31 roots, S1: 10 roots). Before the nerve root infiltration, the low skin temperature areas were observed in 15 patients (36.5%). After infiltoration, skin temperature rose in 26 patients (63.4%). 62 patients (all lumbar disc herniation L5: 36, S1: 26) with single root disturbance were examined for the area of sensory disturbance. The high skin temperature areas were similar to the area of sensory disturbance at both L5 and S1. We thought that one of the causes of increased skin temperature was sympathetic nerve system.
