The clinical scenario describes an ulnar nerve laceration. Studies have shown that the ulnar nerve does not typically have good outcomes after nerve repair. (worse recovery than repairs of the tibial, radial, femoral, and musculocutaneous nerves)
Nerve injuries from gunshot injuries (GSWs) can cause both a direct injury to the nerve as well as surrounding structures (zone of injury). Many factors including age of patient, time to repair, repair level, and length of repair have been shown to be important determinants in nerve recovery following repair. The type of nerve graft (sural, saphenous, etc) used has not shown to be statistically significant in terms of functional recovery after nerve repair.
Secer et al.(J. Neurosurg) reviewed 2210 peripheral nerve lesions in 2106 patients which were injured by a GSW and who were treated surgically. Of the peripheral nerves repaired surgically, the tibial, median, and femoral nerve lesions showed the best recovery rate. The deep peroneal nerve, ulnar nerve, and brachial plexus lesions had the worst recovery.
Secer et al.(Surg. Neur.) found that of 455 patients with 462 ulnar nerve lesions only a good outcome was noted in 15.06% of patients who underwent high-level repair, 29.60% of patients who underwent intermediate-level repair, and 49.68% of patients after low-level repair. The authors also noted that a better functional recovery was noted in patients who were treated earlier.
Figure A shows a distal humerus fracture caused by a GSW.
Answer 1: Earlier nerve repairs typically have better functional results.
Answer 2: The lower level of nerve repair (more distal), the better functional results.
Answer 3: Shorter length of the nerve repair typically leads to better functional results.
Answer 4: Pre and post operative physical rehabilitation after nerve repairs has been shown to have better results.
Secer HI, Daneyemez M, Tehli O, Gonul E, Izci Y. The clinical, electrophysiologic, and surgical characteristics of peripheral nerve injuries caused by gunshot wounds in adults: a 40-year experience. Surg Neurol. 2008 Feb;69(2):143-52; discussion 152. Epub 2007 Oct 29.
PMID:17967482 (Link to Abstract)
Secer HI, Daneyemez M, Gonul E, Izci Y. Surgical repair of ulnar nerve lesions caused by gunshot and shrapnel: results in 407 lesions. J Neurosurg. 2007 Oct;107(4):776-83
PMID:17937222 (Link to Abstract)