Title: Ulnar Index of Median to Ulnar Ring of Ulnar Sensory Nerve Transfer for Distal Injury
Published: 8/19/2011, Updated: 8/19/2011.
Author(s): Ida K. Fox MD, Andrew Yee BS.
Division of Plastic and Reconstructive Surgery, Washington University School of Medicine, St. Louis, MO.
The median to ulnar sensory nerve transfer in the hand is a unique procedure to restore critical sensation to the ulnar border of the hand. In this case, a blast injury to ulnar aspect of the hand resulted in the discontinuity of the ulnar nerve sensory component, soft tissue coverage issues, and subsequent amputation of the small finger. The goals for this case were to restore critical sensation and prevent painful neuroma formation. Nerve grafting was contraindicated due to the extensive zone of injury and suboptimal tissue coverage over the putative site of graft placement. Therefore, a combination of distal sensory nerve transfer, proximal prevention of neuroma, and creative ‘spare parts’ surgery was used to treat this patient. The specific nerve branches transferred to restore sensation to the new ulnar border of the hand was the following: (donor) ulnar aspect of the index finger digital branch of median nerve to (recipient) ulnar aspect of the ring finger digital branch of ulnar nerve. Autologous nerve graft material was used to bridge the gap. In this case, the proximal sensory component of the ulnar nerve was a ‘spare part’ and used as the graft material. To prevent painful proximal neuroma, the proximal end of the sensory component of the ulnar nerve was extended using an acellularized nerve allograft (ANA). The distal end of the ANA was buried in the flexor carpi ulnaris muscle mass. To restore rudimentary sensation to the donor nerve territory (ulnar aspect of index finger), an end-to-side transfer of the ulnar aspect of the index finger digital branch to the radial aspect of the long finger digital branch sensory nerve transfer was performed. This procedure avoided long nerve grafting through the zone of injury at the palm, effectively restore sensation in the critical areas, and prevent proximal painful neuroma of the proximal ulnar nerve stump.