Objective To study the effect of motor nerve implantation after ectopic transplantation of skeletal muscle on nerve regeneration in rat. Methods Sixty Sprague-Dewley male 8 monthold rats were randomly divided into 3 groups: control group,in situ implantation group and ectopic transplantation group. In control group, obturator nerve controlling right gracilis was cut off. In in situ implantation group, the right gracilis was cut off and replanted to its original site, and the obturator nerve was implanted to the muscle. In ectopic transplantation group, the right gracilis was cut off and transplanted to the muscle of the left leg, and the obturator nerve was implanted to the muscle. After 25 weeks, the neurophysiological information was collected through electromyography and the weight of the muscle was measured. Results The potentialwithout control of the nerve existed in control group. There were no significant differences in latency, amplitude and conduct velocity betweenin situ implantation group and ectopic transplantation group(Pgt;0.05).The atrophy of gracilis was dominant incontrol group, the weight of the muscle was 158.0±19.3 mg. The weights of the muscle were 509.6±14.5 mg in ectopic transplantation group and 516.8±12.7 mg in in situ mplantation group, showing no significant difference (P＞0.05). The weights of the muscle in in situ implantation and ectopic transplantation group were larger than that in control group, showing significant difference(P＜0.05). Conclusion Motor nerve implantation after ectopic transplantation of skeletal muscle could prevent the atrophy of the muscle and resume partial function of nerve.
Objective To study the method of reinnervation after ectopic transplantation of the gracilis muscle in rats. Methods Sixty healthy male rats (age, 8 months; weight, 400-500 g) were randomly divided into 3 groups: the control group, the motor reinnervation group, and the sensory reinnervation group. The right gracilis of the rat was cut off, and the muscle was transplanted to the left leg. In the control group, no reinnervation was performed on the obturator nerve; in the sensory reinnervation group, the obturator nerve was coapted with the recipient saphenous nerve; in the motor reinnervation group, the obturator nerve was coapted with the femoral nerve motor branch. After 25 weeks, the weight of the muscle was measured, and the histological examination was performed. Results Atrophy of the gracilis was found to be a dominant effect in the control group, where the weight of the muscle was 204.0±15.3 mg. In the motor reinnervation group, the weight ofthemuscle was 394.8±12.9 mg, and in the sensory reinnervation group, it was 389.2±13.5 mg, with no significant difference between the two groups (P＞0.05). The weight of the muscle in the motor reinnervation group and in the sensory reinnervation group was significantly greater than that in the control group (P＜0.05).The tissue observation revealed that the nerve axon was diffusedin the motor reinnervated group, with no nerve endplates found. The motor nervereinnervated flaps showed the viable axons out to the motor endplates. The histological examination revealed evidence of reinnervation. Conclusion The motor or sensory nerve anastomosis after the ectopic transplantation of the skeletal muscle can prevent the atrophy of the muscle and restorepart of the nerve function.