Peripheral nerve anatomy for regeneration studies in pigs: feasibility of large animal models

The aim of the study was to provide information about the feasibility of peripheral nerve studies in a large animal model for future research. Seven Yorkshire pigs (25-30 kg) were used in a cadaver study. The accessibility, surgical approach, maximum length of possible nerve defect, diameter, and histologic characteristics of the sural, ulnar, laryngeal, and facial nerve were evaluated. All nerves are easily accessible and demonstrate desirable histologic qualities. The differences in nerve length and diameter vary among the nerves studied and a maximum nerve gap of up to 9.62 +/- 0.93 cm for the right sural nerve is recommended considering the interposition of a nerve graft or tissue engineered nerve construct. The facial nerve demonstrates the largest diameter and the highest number of axons. The sural and laryngeal nerve display significantly less myelination compared with the facial and ulnar nerve. The porcine model for the studies of peripheral nerve regeneration is an attractive alternative to other large animal models.