Comparative experimental study on treatment outcome of nerve transfer, using selective C7 nerve root vs. phrenic nerve.

The treatment outcome of nerve transfer using the C7 nerve root or phrenic nerve was compared in a rat experiment. One hundred and twenty SD rats were divided into two groups, one undergoing phrenic nerve transfer to the musculocutaneous nerve, and the other partial ipsilateral C7 (anteriolateral fascicles of the anterior division) to the musculocutaneous nerve. Neurotization outcomes of the two groups were evaluated by comparing the electrophysiologic, histologic, and myophysiologic changes of the biceps muscle. No significant differences were found between parameters from the phrenic nerve transfer group and those from the ipsilateral C7 nerve transfer group. This indicates that the treatment outcome of selective ipsilateral C7 transfer is comparable to that of phrenic nerve transfer. It is the surgery of choice in treating brachial plexus upper-trunk avulsion accompanied by phrenic nerve injury.