A, Outline of lateral arm flap centered over lateral intermuscular septum (dashed circle). B, Initial posterior incision and elevation of flap deep to triceps fascia showing cutaneous branches of posterior radial collateral artery within lateral intermuscular septum. C, Exposure of vascular pedicle. D, Flap elevated on its pedicle with posterior cutaneous nerves to arm and forearm. SEE TECHNIQUE 63.12.