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.