End-to-side nerve repair has re-emerged in the literature in recent years but clinical applications for this technique are not yet fully defined and clinical reports are rare and controversial. Hypothetically, there might be useful functional results performing peripheral end-to-side nerve graft repair using synergistic terminal branches with defined motor function. An end-to-side nerve graft repair bridging from the terminal motor branch of deep branch of the ulnar nerve to the thenar motor branch of the median nerve was performed in non-human primates. The results in this non-human primate model demonstrate the efficacy of end-to-side nerve graft repair at the level of peripheral terminal motor branches. End-to-side neurorrhaphy may present a viable alternative in conditions of unsuitable end-to-end coaptation and inappropriate nerve grafting procedures.