Role of intraoperative neurophysiology in primary surgery for obstetrical brachial plexus palsy (OBPP)

Management of conducting neuroma-in-continuity in primary surgery for obstetrical brachial plexus palsy (OBPP) is still discussed controversially. We present our experience with intraoperative neurophysiological recordings in the management of lesions in continuity in OBPP. A series of ten children with lesions in continuity of the upper brachial plexus is presented. Due to recordable compound nerve action potentials (CNAPs) and muscle response to motor stimulation across the neuroma, five children underwent external neurolysis of neuroma only (neurolysis group). Due to lack of recordable CNAPs or muscle response, resection of neuroma and interpositional nerve grafting were performed in another five children (resection and grafting group). Functional recovery after at least 30 months of follow-up was assessed. There was a marked difference in functional recovery between the neurolysis and the resection and grafting group. Especially, recovery of shoulder function was disappointing after external neurolysis of conducting neuroma-in-continuity. At the end of follow-up, results of shoulder and elbow function after resection of neuroma followed by interpositional nerve grafting were better without exception. Intraoperative neurophysiological recordings face certain difficulties when used in small children with OBPP. Due to overoptimistic assessment of prognosis after intraoperative CNAP recordings and motor stimulation, the functional results after neurolysis of conducting neuroma-in-continuity are disappointing. Resection of neuroma-in-continuity, conducting or not, offers the best opportunity for maximal functional recovery of the compromised upper limb in OBPP. The role of intraoperative neurophysiological techniques should be confined to the diagnosis of root avulsions.