An "Expanded Zone" Concept for Soft Tissue Coverage of the Upper Extremity: Upper Extremity "Expanded Zones".

Vascularized soft tissue coverage of open wounds of the lower extremity has long been predicated on the zone of injury and the available local flap donor site options found therein. A hypothesis was presented decades ago in this journal that attempted to extend a similar approach to simplify upper extremity coverage as well, but appears to have long been forgotten. However, with the emergence of the fasciocutaneous flap and its offspring the perforator flap, now a plethora of additional local flap options within the upper extremity may justify this idea being further considered. Indeed, the upper extremity can arbitrarily be divided into distinct anatomical regions that each has unique characteristics. However, soft tissue requirements that must be restored cannot so simply be restricted by anatomical boundaries, so instead an "expanded zone" concept is more appropriate where comparable regions can be treated in a similar as long as functional fashion. All this must be with the realization that if a suitable local flap option does not exist, the selection of a free tissue transfer with the same preferable composition should instead be chosen, just as would be done in the lower extremity.