Sensate hypothenar perforator free flap for resurfacing large volar surface defect of the digit.

In this report we present a case of large sized volar surface defect of a digit reconstructed by hypothenar perforator free flap coverage. A 57-year-old male patient presented with a 5 × 2 cm sized avulsive injury on his left little finger involving near total loss of the volar surface. The perforator arteries of the hypothenar area were identified around 5-15% on the x-axis and 25-50% on the y-axis (y-axis: a line from the pisiform base to the metacarpophalangeal joint, x-axis: a line perpendicular to the y-axis.) The hypothenar free flap was designed centered on the anticipated location of the perforator artery. Upon dissection, the perforator artery was found as predicted and a superficial palmar vein was saved for venous drainage. In addition, a neighboring cutaneous branch of the ulnar nerve was also saved. The flap survived with satisfactory flap contour, durability, skin color and texture. Five months of follow-up showed acceptable range of motion for joints of the affected digit and nearly full range of motion for the hand. The sensate hypothenar perforator free flap could be considered as a useful surgical option for large sized volar side defects of finger.