A piece of tissue that has been partially detached and used in surgical grafting to fill an adjacent defect or cover the cut end of a bone after amputation.
Flap surgery is a technique in plastic and reconstructive surgery where any type of tissue is lifted from a donor site and moved to a recipient site with an intact blood supply. This is similar to but different from a graft, which does not have an intact blood supply and therefore relies on growth of new blood vessels. This is done to fill a defect such as a wound resulting from injury or surgery when the remaining tissue is unable to support a graft, or to rebuild more complex anatomic structures such as breast or jaw.
Flaps have been used in upper limb surgery for varied indications including coverage of soft tissue defects, interposition and to provide a pliable bed for gliding structures among others.
see Pedicle flap