Abstract
Introduction : We investigated double innervation, innervation of a single muscle by two different nerves, using an end-to-side neurorrhaphy model.
Materials : We used ten male-wistar rats (350-450g).
Method : The sciatic nerve was dissected, and transplanted between the left and right median nerve in an end-to-side fashion. Then, the left median nerve was transected proximal to the neurorrhaphy, In group one, the left median nerve was not repaired. In group two, the left median nerve was repaired immediately after transection. After 180 days, we evaluated nerve regeneration based on dry muscle weight, action potential, electromyography, and histology. End-to-side neurorrhaphy (distal end) was also studied morphometrically with Dil and DiA neural tracers.
Results : In group two, electromyographic and electrophysiological findings showed the possibility of double innervation. In addition, regenerating axons from both the grafted sciatic and median nerves were observed in the distal left median nerve.
Discussion : Our findings suggest double innervation of a single muscle, however, further study of individual muscle fibers is still required.
