Anatomic basis of the lower trapezius musculocutaneous flap.

Differences in the description of the blood supply of the lower trapezius m. and the fact that all former findings are based on very few cases caused us to reinvestigate the arterial supply of the lower trapezius m. Based on the anatomic investigation of 70 human cadavers, the trapezial branch of the dorsal scapular a. was found to be the constant vessel to the lower trapezius m. The origin of the dorsal scapular a., however, was found to be very variable. In 45% it was a direct branch of either the subclavian a. or the costocervical trunk. In the remaining 55% the dorsal scapular a. formed different trunks with the superficial cervical a. and/or suprascapular a. branching off either the subclavian a., the thyrocervical trunk, or the internal thoracic a. Additional segmental musculocutaneous perforators also supply the lower part of the trapezius m. and the overlying skin. Consequently, the lower or ascending part of the trapezius m. has a vascular pattern type V. Thus, the lower trapezius musculocutaneous flap merits consideration in head and neck reconstruction.