Effective reinnervation of the quadriceps femoris by spinal ventral root cross-anastomosis in rats

Abstract

To study the effective recovery of the quadriceps femoris by spinal ventral root cross-anastomosis in rats. End-to-end anastomosis was performed between the left L(1) and L(3) ventral roots using autogenous nerve graft, and the right L(1) and L(3) roots were left intact. In control animals, the left L(3) ventral root was cut and shortened, and anastomosis was not performed. Six months postoperatively, the movement of low extremities was detected by electrophysiological examination, hindlimb locomotion and basso, beattie and bresnahan (BBB) scoring at one, three, seven, 14, 21 and 28 days after SCI. Fluorescence retrograde tracing with TRUE BLUE (TB) and HE staining were performed to observe the nerve regeneration. Six months after surgery, the anastomotic nerve was smooth and not atrophic. The amplitudes of action potential were 7.63 ± 1.86 mV and 6.0 ± 1.92 mV respectively before and after the spinal cord hemisection. The contraction of left quadriceps femoris was induced by a single stimulation of the anastomotic nerve. The locomotion of left hindlimb was partially restored after spinal cord hemisection while creeping and climbing. In addition, there was significant difference in the BBB score at one, three and seven days after SCI. TB retrograde tracing and neurophysiologic observation indicated efficient reinnervation of the quadriceps femoris. The cross-anastomosis between spinal ventral root can partially reconstruct the function of quadriceps femoris following SCI and may have clinical implication for the treatment of human SCI.