Sympathetic skin response in incomplete spinal cord injury with urinary incontinence

OBJECTIVES: Sympathetic skin response (SSR) is a test for evaluation of the sympathetic sweat gland pathways, and it has been used to study the central sympathetic pathways in spinal cord injury (SCI). This study aimed to assess the autonomic pathways according to normal or abnormal SSR in urinary incontinence patients due to incomplete spinal cord injury. MATERIALS AND METHODS: Suprapubic, palmar, and plantar SSR to the peripheral nerve electrical stimulation were recorded in 16 urinary incontinence patients with incomplete spinal cord injury at various neurological levels and in 30 healthy control subjects. RESULTS: All the recordings of SSR from the incomplete SCI patients with urinary incontinence as compared with their counterparts in the control group showed significantly reduced amplitudes with more prominent reduction in the suprapubic area recording site (P value < 0.0004). SSR with significantly prolonged latencies were recorded from palm and plantar areas in response to suprapubic area and tibial N stimuli, respectively (P value < 0.02). In this study, a significantly higher stimulus intensity (P value < 0.01) was needed to elicit SSR in the cases compared with the control group. CONCLUSION: This study showed abnormal SSR in urinary incontinence patients due to incomplete SCI. In addition, for the first time we have described recording of abnormal SSR from the suprapubic area as another way to show bladder sympathetic system involvement.