Hemi-contralateral C7 transfer in traumatic brachial plexus injuries: outcomes and complications

In brachial plexus injuries with nerve root avulsions, the options for nerve reconstruction are limited. In select situations, half or all of the contralateral C7 (CC7) nerve root can be transferred to the injured side for brachial plexus reconstruction. Although encouraging results have been reported, CC7 transfer has not gained universal popularity. The purpose of this study was to critically evaluate hemi-CC7 transfer for restoration of shoulder function or median nerve function in patients with severe brachial plexus injury.

A retrospective review of all patients with traumatic brachial plexus injury who had undergone hemi-CC7 transfer at a single institution during an eight-year period was performed. Complications were evaluated in all patients regardless of the duration of follow-up. The results of electrodiagnostic studies and modified British Medical Research Council (BMRC) motor grading were reviewed in all patients with more than twenty-seven months of follow-up.

Fifty-five patients with traumatic brachial plexus injury underwent hemi-CC7 transfer performed between 2001 and 2008 for restoration of shoulder function or median nerve function. Thirteen patients who underwent hemi-CC7 transfer to the shoulder and fifteen patients who underwent hemi-CC7 transfer to the median nerve had more than twenty-seven months of follow-up. Twelve of the thirteen patients in the shoulder group demonstrated electromyographic evidence of reinnervation, but only three patients achieved M3 or greater shoulder abduction motor function. Three of the fifteen patients in the median nerve group demonstrated electromyographic evidence of reinnervation, but none developed M3 or greater composite grip. All patients experienced donor-side sensory or motor changes; these were typically mild and transient, but one patient sustained severe, permanent donor-side motor and sensory losses.

The outcomes of hemi-CC7 transfer for restoration of shoulder motor function or median nerve function following posttraumatic brachial plexus injury do not justify the risk of donor-site morbidity, which includes possible permanent motor and sensory losses.