A morphological comparison of interposed freeze-thawed skeletal muscle autografts and interposed nerve autografts in the repair of the rat facial nerve

Freeze-thawed co-axially aligned skeletal muscle autografts provide a new concept in peripheral nerve repair, and are being investigated in the repair of mixed motor/sensory nerves. These grafts provide an orientated matrix of large basement membrane tubes through which regenerating axons can migrate and reinnervate the distal nerve. Using the buccal branch of the rat facial nerve as a model, we compared five freeze-thawed muscle autografts with five interposed nerve autografts. Some 300 days after grafting, the morphology of the distal nerve was evaluated. When the two groups were assessed morphometrically, it was found that nerve grafts showed a small but significant improvement over muscle grafts in respect of indices of the fibre maturation.