The total volar forearm musculocutaneous free flap for reconstruction of extended forequarter amputations

Forequarter amputation is performed for resection of large, invasive tumors of the shoulder girdle region. A substantial defect can usually be closed with local or regional flaps; however, a subset of the forequarter amputation group has emerged at this institution with more complex issues. These patients have extensively more invasive posterior tumors, some with chest wall/rib invasion. Local/regional flaps in these situations are inadequate, and free tissue transfer is the only viable option. The forequarter specimen can sometimes be used as a donor site, thereby eliminating the usual donor site morbidity. Variations of the total forearm free flap have been sparsely described in the literature--the majority being case reports of either pure fasciocutaneous or "filet of forearm" flaps. We report a series of 4 patients treated over a 5 year period at this institution using the previously undescribed total volar forearm musculocutaneous free flap based on the brachial artery and its venae comitantes. This flap includes the entire musculature of the volar forearm with fasciocutaneous extensions on either side of the musculocutaneous unit. All potentially ischemic dorsal musculature is discarded, leaving a flap that has central bulk and a relatively large dimension. The entire flap remains extremely well vascularized, and a substantial surface area of as much as 45 x 25 cm can be attained. A pedicle as long as 20 cm can be dissected as far proximally in the arm as is oncologically safe. A single artery and vein are anastomosed to either the intrathoracic or neck vessels. All four flaps survived completely with uncomplicated wound healing. The total volar forearm musculocutaneous flap is extremely well vascularized and highly reliable. The flap as described provides the ideal combination of large surface area, muscle bulk, and long vascular pedicle. It can be dissected rapidly to minimize ischemic time and could therefore be applicable to traumatic forequarter amputations. It has become the flap of choice for reconstruction of extended oncological forequarter amputation defects.