Behavioral recovery and motor reinnervation outcomes after peripheral nerve transection with microsuture or nerve tape repair.

BACKGROUND: Recovery after peripheral nerve injury (PNI), even with surgical intervention, is often poor. The current standard in surgical repair of PNIs, microsuture of the severed epineurium is technically demanding, time-consuming, and routinely results in fascicular misalignment. NEW METHOD: Nerve Tape is a coaptation device that circumvents the need for microsuture. Nerve Tape repairs improve fascicular alignment, nerve conduction velocities, as well as muscle and axon morphologies compared to microsuture repairs. However, the efficacy of Nerve Tape for small diameter nerve repairs is understudied, and no reports exist directly comparing sexes. We compared sensory and locomotor recovery as well as the pattern of motor reinnervation after sciatic nerve transection and repair with either microsuture or Nerve Tape in rats of both sexes. Young adult male and female Lewis rats received a sciatic nerve transection repaired with either microsuture or Nerve Tape. Locomotor and sensory testing was performed weekly post-injury. At either 8- or 12-weeks post-repair, motoneurons whose axons had regenerated into the anterior tibialis muscle were retrogradely labeled, allowing for assessment of motoneuron number and spinal location. RESULTS AND COMPARISON WITH EXISTING METHODS: Nerve Tape repairs took significantly less time than microsuture. Behavioral recovery outcomes were comparable after microsuture and Nerve Tape repairs and did not differ between sexes. Retrograde labeling of motoneurons demonstrated that motor axons successfully regenerated to appropriate and inappropriate muscles regardless of repair type or sex. CONCLUSION: Our data supports the efficacy of Nerve Tape to repair small diameter nerve injuries in both males and females.