This article provides a strategy for selective neurotization of the anterior interosseous nerve using the full length of the phrenic nerve and a small sural nerve graft in patients with a complete brachial plexus palsy based on cadaveric dissection and a case report. Cadaveric dissections were performed on thirty-four median nerves from 17 embalmed cadavers. Three main fascicular groups were identified in the distal half of the arm. The anterior fascicular group is composed of branches to the pronator teres and the flexor carpi radialis. The posterior fascicular group is composed of the anterior interosseous nerve and branches to the palmaris longus. The middle fascicular group included branches to the flexor digitorum superficialis, the palmar cutaneous branch, and all motor and sensory branches to the hand. A case report was provided of a 24 year old man with a complete brachial plexus palsy who underwent nerve transfers including harvesting a full length of the phrenic nerve in the thoracic cavity through a thoracotomy exposure along the fourth intercostal space. The nerve was transferred through the second intercostal space with a 5cm sural nerve graft to the posterior fascicular group of the median nerve. The patient also underwent other nerve transfers including a spinal accessory nerve to the musculocutaneous nerve, contralateral C7 nerve root to the radial nerve with vascularized ulnar nerve graft and the contralateral lateral pectoral nerve to the suprascapular nerve with the use of a sural nerve graft. Sixteen months after surgical reconstruction, nearly full range of flexion at the interphalangeal joints of all digits and at the wrist was observed when the patient took a deep breath. FPL and FDP were graded 4 / 5.
This study provides a rational approach to selective neurotization of the interosseous nerve in patients with brachial plexus palsy. It makes use of the phrenic nerve via a dramatic thoracotomy dissection in order to minimize sural nerve grafting. There were no complications noted in the one case report provided, however, a review of risks associated with such an extensive operative intervention would be beneficial in future studies of a larger series of patients. The ability to selectively reanimate the motor portions of the branches of the median nerve in order to improve hand pinching grasp in a reliable fashion may provide significant improvement to the surgical reconstruction of severe brachial plexus injuries.
Journal of Bone and Joint Surgery