Vascular basis of intrinsic muscle flaps in the hand

Background: Intrinsic hand muscles can occasionally be used as pedicled flaps for wound coverage or functioning transfer in hand trauma. The purpose of this study was to define the vascular supply of the individual intrinsic muscles of the hand for potential use of these muscles as muscle flaps. Methods: In part A, 10 fresh cadavers were injected using a lead oxide-gelatin injection technique. The intrinsic muscles were meticulously dissected, removed, and radiographed. The number, type, and diameter of the vascular pedicles of each muscle and their distribution within the muscle were analyzed. The area of the vascular territory supplied by each source vessel was calculated. In part B, 10 embalmed cadavers were injected with red latex and a similar dissection protocol was followed. Results: The 18 hand muscles each received an average of 3 +/- 1 vascular pedicles. The average diameter was 0.8 +/- 0.2 mm; the length and width of the area supplied by each pedicle was 2.2 +/- 0.4 cm and 1.0 +/- 0.2 cm, respectively. The vascular territories of the majority of hand muscles were aligned longitudinally along their long axes. Nine intrinsic hand muscles have been identified that can potentially be used as a muscle flap or musculocutaneous or musculoosseous flap. Conclusions: The size and course of the vascular pedicles to the hand muscles are variable. This anatomical study provides an improved understanding of the vascular supply of the intrinsic muscles of the hand and provides further information to assist in the design of intrinsic hand muscle transfer.