Adequate blood flow is essential for reinnervation in neurovascular skin flaps

The effect of arterial and venous ischaemia on reinnervation of skin flaps after transsection and resuture of the epigastric nerve was investigated in rat groin flaps. The results were compared with those in corresponding flaps with adequate blood flow. Arterial or venous ischaemia was induced by ligation of the epigastric artery or vein. The reinnervation of the flaps was studied after a 20-week healing period using specific antisera for calcitonin gene-related peptide (CGRP) in sensory nerves, and neuropeptide Y (NPY) in adrenergic nerves. Arterial ischaemia clearly and significantly hampered reinnervation. Venous ischaemia was even more harmful and practically no regenerated nerves were detected in the flaps. We conclude that adequate blood flow is critical for sensory and adrenergic reinnervation in skin flaps.