Spinal nerve root repair and reimplantation of avulsed ventral roots into the spinal cord after brachial plexus injury

Object. The authors review the first series of 10 cases in which injured in traspinal brachial plexus were surgically repaired. They describe the techn ique of spinal cord implantation or repair of ruptured nerve roots, as well as patient outcome. Methods. Spinal root repair/implantation was performed from 10 days to 9 mo nths postinjury. There were nine male patients and one female patient. Post operatively in most cases, regeneration of motor neurons from the spinal co rd to denervated muscles could be demonstrated. The first signs of regenera tion were noted approximately 9 to 12 months postoperatively. Useful functi on with muscle power of at least Medical Research Council Grade 3 occurred in three of 10 cases. Magnetic brain stimulation studies revealed a normal amplitude and latency from the cortex to reinnervated muscles on surgically treated and control sides. A certain degree of cocontraction between antag onistic muscles (for example, biceps-triceps) compromised function. With ti me there was a reduction of cocontractions, probably due to spinal cord pla sticity. In these cases there was also, surprisingly, a return of sensory f unction, although the mechanism by which this occurred is uncertain. Sensor y stimulation (thermal and mechanical) within the avulsed dermatomes was pe rceived abnormally and/or experienced at remote sites. There was some retur n of patients' sense of joint position. Conclusions. A short time lag between the accident and the surgery was reco gnized as a significant factor for a successful outcome. Reimplantation of avulsed nerve roots may be combined with other procedures such as nerve tra nsfers in severe cases of brachial plexus injury.