Radial Forearm Free Flap in Intraoral Reconstruction



Radial Forearm Free Flap in Intraoral Reconstruction


D. S. SOUTAR

I. A. McGREGOR





The radial forearm flap is a fasciocutaneous flap based on the radial artery and venae comitantes, together with the subcutaneous forearm veins. Several reports (1, 2, 3, 4, 5) already have demonstrated the versatility, usefulness, and reliability of this flap both as a pedicled flap in reconstructive surgery of the hand and as a free flap in the expanding field of free tissue transfer. This flap can be used as either a fasciocutaneous flap or as an osteofasciocutaneous flap (6, 7) for reconstructing defects resulting from excision of intraoral malignancies.




ANATOMY

Much of the skin of the forearm is supplied by the radial artery, which is covered proximally by the fleshy belly of the brachioradialis. It soon emerges distally between the brachioradialis and the flexor carpi radialis to lie superficially, covered only by skin, subcutaneous tissue, and the deep fascia.

The artery, together with its two venae comitantes, is invested in a condensation of the deep fascia known as the lateral intermuscular septum (Fig. 202.1). This septum separates the flexor and extensor compartments of the forearm and is attached to the periosteum of the radius distal to the insertion of pronator teres.

The artery gives off branches that pass through the deep fascia to supply the underlying flexor muscles and branches that spread out on the deep fascia to form a fascial plexus and
supply the overlying skin. By means of this vascular network, the radial artery can supply the skin of the palmar and radial aspects of the forearm and provide a periosteal blood supply to the distal radius.






FIGURE 202.1 Fasciocutaneous flap. Cross section through the forearm distal to pronator teres showing the position of the radial artery and the plane of dissection for elevation of the fasciocutaneous flap. (From Soutar et al., ref. 7, with permission.)

Venous drainage of the forearm flap is provided by two venae comitantes that accompany the artery and a variable pattern of subcutaneous forearm veins that drain into the cephalic, basilic, and median cubital veins. Routinely, both venous systems communicate by means of a constant branch from the venae comitantes, which drains into the median cubital vein.

The forearm flap is ideally suited for free-tissue transfer because the artery can be readily palpated for much of its length and the superficial subcutaneous veins of the forearm are easily identified. The diameter of the artery, usually in excess of 3 mm, remains relatively constant from its origin to the wrist joint, making anastomosis of either proximal or distal ends equally straightforward. Furthermore, the absence of significant arterial disease, particularly atheroma in elderly patients, has been most remarkable.


FLAP DESIGN AND DIMENSIONS

Using a template, a radial forearm flap can be designed to replace the amount of resected tissue accurately, thereby minimizing distortion and functional disturbance within the oral cavity. The radial artery, which is subcutaneous for much of its length in the forearm, can be palpated and its course marked on the skin surface. The superficial subcutaneous forearm veins are similarly marked, and the appropriately designed flap is outlined.

The arteriovenous system on which the forearm flap is based is capable of supplying all the skin of the forearm from above the elbow to the wrist, except for a narrow strip overlying the ulna posteriorly. In practice, such large flaps are not required in intraoral reconstruction.

The quality of the skin and the length of the vascular pedicle required for easy anastomosis most often influence the choice of donor site. The presence and distribution of hair on the forearm may influence site selection (Fig. 202.2), although such hairs tend to be short and fine and cause little trouble following flap transfer.

Only gold members can continue reading. Log In or Register to continue

Jun 26, 2016 | Posted by in General Surgery | Comments Off on Radial Forearm Free Flap in Intraoral Reconstruction
Premium Wordpress Themes by UFO Themes