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.

Reinnervation after nerve suture in rat groin flaps.

Regeneration of sensory and adrenergic nerves in the skin was studied in rats. The aim was to investigate the effect of reanastomosing the cut nerve ends of the nerve trunk leading to the microvascular groin flap. Reinnervation was demonstrated immunohistochemically using calcitonin gene-related peptide (CGRP) as marker for sensory nerves, neuropeptide Y (NPY) and tyrosine hydroxylase (TH) as markers for adrenergic nerves and Protein Gene Product 9.5 (PGP 9.5) as general neuronal marker. It was demonstrated that reanastomosing of the nerve trunk was favourable for both the sensory and sympathetic reinnervation of microsurgical flaps.