Sihler's staining of the cutaneous nerves of the leg and its implications for sensory reconstruction.

INTRODUCTION: This study aimed to reveal the entire cutaneous nerve distribution pattern of the leg and provide a morphological basis for sensory reconstruction during skin flap transplantation. MATERIALS AND METHODS: Twelve adult cadavers were fixed with formalin, and the whole leg skin with subcutaneous fat was removed close to the muscle surface. The cutaneous nerves were visualized using modified Sihler's staining to reveal the distribution and innervation density of the cutaneous nerves. RESULTS: The saphenous nerve innervated the anterior part, 82.2% of the upper-middle region of the lateral part of the anterolateral leg, and the upper 63.4% of the medial posterior leg. The superficial peroneal nerve innervated 90.1% of the lateral lower one-third of the anterolateral leg. The medial sural cutaneous nerve covered 26.4% of the posterior leg. The lateral sural cutaneous nerve covered 42.3% (approximately 28.6% overlap with the saphenous nerve) of the upper-middle region of the anterolateral and posterolateral leg. The number of branches differed between certain cutaneous nerves in the leg. Communications were observed between the arborizations of the four cutaneous nerves mentioned above. The highest density of primary and secondary nerve branches was observed in the upper one-third of the lateral posterior leg. The upper one-third of the posteromedial leg contained the highest density of intracutaneous nerve branches and highest number of total nerve branches. CONCLUSIONS: These results may be used to map sensory regions when designing leg skin flaps for reconstruction surgery to obtain improved sensory recovery.