Outcomes of anterior interosseous nerve transfer to restore intrinsic muscle function after high ulnar nerve injury.

Traumatic high ulnar nerve injuries have historically resulted in long-term loss of hand function due to the long re-innervation distance to the intrinsic muscles. Transfer of the anterior interosseous nerve (AIN) to the deep motor branch of the ulnar nerve (MUN) is proving promising in these patients. The purpose of this study was to evaluate the outcomes and efficacy of this procedure in our series. Eligible high ulnar nerve injury patients who underwent AIN to MUN nerve transfer were evaluated with a mean follow-up of 17 months. Data including demographics, injury details, surgical procedures, and outcomes were collected. A review of the current literature was performed for comparison. Sixteen patients had AIN to MUN transfer, mean age of 39.4 years, and a median delay from injury to nerve transfer of 0.8 months. The injury site was above the elbow in 5 cases, at the elbow in 8 cases, and in the proximal forearm in 3 cases. The majority were sharp transection, with the remaining from blast injuries, traumatic traction, and one post-traumatic neuroma resection. Transfer was performed end-to-end in 7 cases, hemi end-to-end in 7 cases, and supercharged end-to-side in 2 cases. Five patients achieved intrinsic muscle recovery of MRC 4+ and thirteen gained MRC 3 or above. The AIN to MUN nerve transfer provides meaningful intrinsic recovery in the majority of traumatic high ulnar nerve injuries. This procedure should be routinely considered, however, warrants further research to validate the optimum technique.

An evidence-based structured review to assess the results of common peroneal nerve repair.

BACKGROUND: When is common peroneal nerve repair worthwhile? What is the effect of delayed repair? What is the maximum length of graft that can be used? This study aimed to address these questions by assessing the current literature and ascertaining the predictors of outcome that would guide peripheral nerve surgeons in determining the correct treatment of common peroneal nerve injury. METHODS: After an extensive literature review, 28 studies (1577 repairs) were assessed. The authors evaluated outcomes, using the British Medical Research Council grading for motor recovery, where M4 or above was considered a good outcome, and related them to delay, graft length, mechanism of injury, and age. RESULTS: Good outcomes (M4 and M5) were obtained in 45 percent of cases; more specifically, 80 percent for neurolysis, 37 percent for direct suture, and 36 percent for nerve graft. Excluding neurolysis, good outcomes were obtained in 44 percent of repairs performed within 6 months but in only 12 percent of repairs performed after 12 months (p=0.0046), and in 64 percent of repairs using grafts shorter than 6 cm but in only 11 percent of repairs using grafts longer than 12 cm (p=0.0002). Age did not influence outcome (p=0.2750). CONCLUSIONS: Common peroneal nerve repair was worthwhile in approximately half of all cases. The authors suggest that the results of common peroneal nerve repair will be suboptimal if surgery is performed more than 12 months after injury or if a graft of more than 12 cm is required.