Ultrasonographic evaluation of the median and sciatic nerves in hemiplegic patients after stroke.

Abstract

The aim of this study was to evaluate morphologically and electrophysiologically the peripheral nerves of hemiplegic patients. Thirty-three (18 women and 15 men) stroke patients were recruited. The mean (SD) age was 55.6 (11.3) yrs, and the mean (SD) disease duration was 14.2 (16.0) mos. Motor nerve conduction study of the median, ulnar, fibular, and tibial nerves as well as sensory nerve conduction study of the median, ulnar, and sural nerves were performed. Diameters and cross-sectional area (CSA) measurements of the median (wrist/midarm levels) and sciatic nerves (midthigh level) were acquired using a 7- to 12-MHz linear probe. The values of the nonparetic limbs were taken as controls. Prolonged distal latency and slowed motor conduction velocity of the tibial nerve as well as reduced amplitudes of the median and ulnar nerves were observed on the paretic sides when compared with those of the nonparetic sides (all P < 0.05). The median and sciatic nerve cross-sectional area values were found to be smaller on the paretic sides when compared with the nonparetic sides (all P < 0.05). The median and ulnar nerve compound muscle action potential amplitudes (paretic side) were positively correlated with arm/hand Brunnstrom Motor Recovery Stage, disease duration, motor Functional Independence Measure score, and Functional Ambulation Category. The peripheral nerves of stroke patients seem to be affected--morphologically and electrophysiologically--on the paretic side.