Jonathan Winograd, M.D.
Assistant Professor Harvard Medical School
Mr. F is a 59 year old gentleman who was transferred from an outside hospital with a work related injury. While grasping a piece of wood on a conveyor belt, his arms became caught within the conveyor and he was trapped against the belt for several minutes. He sustained multiple deep burns to his bilateral upper extremities and chest, as well as left both bone open forearm fractures, an open humerus fracture with shoulder dislocation, left rib fractures, a left hemothorax, a left total brachial plexus palsy, and a right medial elbow burn directly over the cubital tunnel with exposure and severe contusion of the ulnar nerve. He was stabilized at the outside hospital, underwent washout and reduction of the humerus fracture and forearm fractures with external fixation, a chest tube placement, and subsequently was transferred to MGH.
His neurologic exam on arrival demonstrated a complete brachial plexus palsy with an insensate upper extremity on the left side as well as numbness in the ulnar nerve distribution on the right side with intrinsic muscle paralysis as well as flexor digitorum longus palsy of the small and ring fingers. His humerus fracture and his both bone forearm fractures underwent washout and ORIF by the orthopedic trauma service. His shoulder was not able to be stably reduced. He was then evaluated by the plastic surgery hand service. Treatment of his brachial plexus injury was deferred at that point given the severity of his shoulder injury, both bony and soft tissue and the need for nerve conduction studies and EMG evaluation. His burns were treated with excision and grafting except in the left arm, where there was medial exposure of his brachial artery and vein and brachial plexus, and his right elbow, where the ulnar nerve was exposed over a 5 cm span and appeared necrotic.
At that point, he was taken to the OR by the plastic surgery hand service for soft tissue reconstruction of his bilateral upper extremities and for ulnar nerve reconstruction at the right elbow. At that time, it was noted that his ulnar nerve, despite careful wound care, appeared frankly necrotic at the level of the cubital tunnel. His left musculocutaneous nerve was also noted at the time to be frayed at the mid biceps level.
Right elbow with exposed necrotic ulnar nerve and left arm with exposed brachial vessels and frayed musculocutaneous nerve.
Treatment Dilemma: treatment options for his brachial plexus injury of the left upper extremity and his ulnar nerve injury of the right elbow both for 1) soft tissue and 2) nerve injuries?
The brachial vessels and terminal branches of the brachial plexus were covered with a latissimus dorsi flap and split thickness skin grafting, with the idea of both covering the exposed vessels and nerves as well as allowing for future reconstruction if necessary. His right elbow wound was further debrided and the ulnar nerve, after excision of grossly necrotic nerve at the elbow, was left with a 7 cm gap at the cubital tunnel after the nerve ends proximally and distally were transposed out of the cubital tunnel. The nerve was grafted with five cables of sural nerve autograft. The large wound was covered with a pedicled radial artery forearm flap. The radial forearm was selected because of its low profile and excellent pliability for elbow motion restoration. Additionally, an end to end AIN to deep motor branch nerve transfer was performed and the donor site in the distal forearm was skin grafted. The patient subsequently healed all of the above wounds. He did require some additional grafting by the burn service for his wounds, which all healed uneventfully.
Clockwise from upper left. Left arm coverage with latissimus dorsi flap, with delayed skin grafting. Right ulnar nerve cable grafts x 5. AIN to deep motor branch transfer. Distal forearm neurolysis of deep motor branch from ulnar nerve in preparation for transfer.
Radial forearm flap elevated and transposed. Radial forearm flap in place with adjacent split thickness skin graft.
Diagnostic and Treatment Dilemma: What additional testing is needed at this point for the patient in regard to his brachial plexus injury and his reconstructed ulnar nerve? Is there a role for supercharged end-to-side transfer vs. end to end transfer? Outcome data to guide the clinician is lacking at this point.
In follow up, 2 months post injury, he began to recover left brachial plexus function, with diminished but present sensation to light touch present in the MABC, LABC, radial sensory nerve and axillary nerve distributions, as well as flexion and extension of his fingers. By six months, his brachial plexus injury has recovered significantly, with return of voluntary elbow, wrist, and hand movement, and diminished sensation to light touch in the palmar skin of the radial three digits with absent sensation in the ulnar digits. Of note, his nerve conduction studies and EMG were deferred originally because of concerns over his recent latissimus dorsi flap and skin grafts. By two months, he began to exhibit clinical recovery and his studies were deferred again. By six months, they did not appear to be necessary.
His right elbow wound healed well after the pedicled radial forearm flap. He can extend his elbow to -20º, with full flexion. His right hand and wrist has a full range of motion but he has no voluntary contraction of his FDP at this time. He has no clawing but does have guttering and first web space atrophy at 6 month follow up. He has grip strength with a Jamar dynamometer of 40 lbs., and tip, chuck and lateral pinch of 8, 9, and 9.5 lbs. respectively. He remains insensate in the ulnar nerve distribution of his right hand.