The contralateral C7 nerve has been used as a donor nerve for repair of the brachial plexus root avulsion injury.In the history of contralateral C7 nerve transfer, there are four route: subcutaneous route, retro-sternocleidomastoid route, prespinal route and modified prespinal route.In this research, we examined 32 specimens for the study of modified prespinal route.The route has several anatomic characteristics as follows: (1) C7 vertebra slopes posteriorly in the sagittal plane, its anterior tubercle of transverse process is small or non-existent, and the pedicle orginates more posteriorly.(2) The triangle interval which was constituted by inferior oblique part of longus colli muscle, C6 transverse process, C6/C7 vertebra and the intervertebral disk, can be passed through by the sectioned C7 nerve easily.(3) There is no significant tissue under angular interval except C7 and C8 nerve root.(4) A certain space exists between esophagus and C7 vertebra, and can be dissected easily.So we believe that contralateral C7 nerve transfer through the modified prespinal route can avoid impairing significant tissues before C7 nerve root at donor side, and lessen possibility of nerve entrapment postoperatively.