Free anterolateral thigh flap for reconstruction of head and neck defects following cancer ablation

Thirty-seven consecutive free anterolateral thigh flaps in 36 patients were transferred for reconstruction of head and neck defects following cancer ablation between January of 1997 and June of 1998. The success rate was 97 percent (36 of 37), with one flap lost due to a twisted perforator. The anatomic variations and length of the vascular pedicle were investigated to obtain better knowledge of anatomy and to avoid several surgical pitfalls when it is used for head and neck reconstruction. The cutaneous perforators were always found and presented as musculocutaneous or septocutaneous perforators in this series of 37 anterolateral thigh flaps. They were classified into four types according to the perforator derivation and the direction in which it traversed the vastus lateralis muscle. In type I, vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 56.8 percent of cases (21 of 37), and they were 4.83 +/- 2.04 cm in length. In type II, horizontal musculocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 27.0 percent of cases (10 of 37), and they were 6.77 +/- 3.48 cm in length. In type III, vertical septocutaneous perforators from the descending branch of the lateral circumflex femoral artery were found in 10.8 percent of cases (4 of 37), and they were 3.60 +/- 1.47 cm in length. In type IV, horizontal septocutaneous perforators from the transverse branch of the lateral circumflex femoral artery were found in 5.4 percent of cases (2 of 37). They were 7.75 +/- 1.06 cm in length. The average length of vascular pedicle was 12.01 +/- 1.50 cm, and the arterial diameter was around 2.0 to 2.5 mm; two accompanying veins varied from 1.8 to 3.0 mm and were suitable for anastomosis with the neck vessels. Reconstruction of one-layer defect, external skin or intraoral lining, was carried out in 18 cases, through-and-through defect in 17 cases, and composite mandibular defect in two cases. With increasing knowledge of anatomy and refinements of surgical technique, the anterolateral thigh flap can be harvested safely to reconstruct complicated defects of head and neck following cancer ablation with only minimal donor-site morbidity.     

Combined anterolateral thigh flap and vascularized fibula osteoseptocutaneous flap in reconstruction of extensive composite mandibular defects.

Extensive composite defects of the oromandibular area are usually created after the surgical treatment of T3 and T4 cancers, requiring complex reconstructive plastic surgical procedures. The preferred treatment method for this type of defect is reconstruction with two free flaps. The use of the vascularized fibula osteoseptocutaneous flap for the bone and inner lining defect is well known and accepted. Among the flaps that can be used for the outer lining and soft-tissue reconstruction, the two most commonly used have been the forearm flap and the rectus abdominis myocutaneous flap. However, these flaps have some disadvantages that restrict their use for this purpose. The forearm flap is usually too thin to cover the fibular bone and reconstruction plate, and the rectus abdominis myocutaneous flap can cause a subclinical reduction in abdominal strength. Both radial forearm and rectus abdominis myocutaneous flaps are difficult to harvest during tumor excision. Because of these drawbacks, over the past several years the authors have preferred to use the anterolateral thigh flap for outer face, neck, and submandibular region reconstructions. From October of 1998 to June of 2000, 22 extensive composite mandibular defect reconstructions using the free anterolateral thigh flap, combined with the vascularized free fibula osteoseptocutaneous flap, were performed at the Chang Gung Memorial Hospital. Complete flap survival was 90.9 percent (40 of 44 flaps). Complete loss was seen in an anterolateral thigh flap, which was then reconstructed with a pectoralis major myocutaneous pedicled flap (2.3 percent). There were five venous problems: three in osteoseptocutaneous free fibula flaps, the other two in anterolateral thigh flaps; all were revised immediately. However, the skin islands of two osteoseptocutaneous free fibula flaps and one anterolateral thigh flap developed partial necrosis (6.8 percent). The other complications were compartment syndrome in the leg in one patient, external carotid artery rupture in one patient, three donor-site infections in two patients, three neck wound infections, and one myocardial insufficiency; all were treated properly. Thirteen patients underwent revision procedures 6 months after the first operation. These procedures included debulking of the flap or revision of the mouth angle or both. Trismus or intraoral contraction was noted in none of these patients. In conclusion, the free anterolateral thigh flap combined with the vascularized fibula osteoseptocutaneous flap seems to be a good choice in the reconstruction of the extensive composite defects of the oromandibular region aesthetically and functionally.     

Comparison of the radial forearm flap and the thinned anterolateral thigh cutaneous flap for reconstruction of tongue defects: an evaluation of donor-site morbidity

The radial forearm flap is commonly used for reconstruction of tongue defects following tumor extirpation. This flap is easy to harvest and offers thin tissue with large-caliber vessels. However, its use leaves behind a conspicuous aesthetic deformity in the forearm and requires the sacrifice of a major artery of that limb, the radial artery. The anterolateral thigh cutaneous flap has found clinical applications in the reconstruction of soft-tissue defects requiring thin tissue. More recently, in a thinned form, the anterolateral thigh flap has been used for reconstructing defects of the tongue with functional results equivalent to that of the radial forearm flap. For the reconstruction of tongue defects, these two flaps could provide similar soft-tissue coverage, but they seem to result in different donor-site appearances. The donor site is closed primarily, leaving only a linear scar that is inconspicuous with normal clothing, and no functional deficit is left behind in the thigh. Thus, for the supply of flaps for tongue defects, a comparison between the radial forearm flap and the anterolateral thigh flap donor sites is provided in this study. Between December of 2000 and August of 2002, 41 patients who underwent reconstruction of defects of the tongue using either a radial forearm flap or an anterolateral thigh flap were evaluated. The focus was on the evaluation of the functional and aesthetic outcome of the donor site after harvesting these flaps for the purpose of reconstructing either total or partial tongue defects. Finally, a comparison was performed between the donor sites of the two flaps. The disadvantages of the radial forearm flap include the conspicuous unattractive scar in the forearm region, pain, numbness, and the sacrifice of a major artery of the limb. In some patients, the donor-site scar of the forearm acted as a social stigma, preventing these patients from leading a normal life. In contrast, the anterolateral thigh cutaneous flap, after thinning, achieved the same results in reconstructing defects of the tongue without the associated donor-site morbidity. Most importantly, the donor site in the thigh could be closed primarily in almost all patients without any functional deficit. The thinned anterolateral thigh cutaneous flap is a viable substitute for the radial forearm flap when reconstructing defects of the tongue. The results achieved are similar to those of the radial forearm flap, and the donor-site morbidity is significantly decreased.     

Three-dimensional reconstruction of the oral cavity using the free anterolateral thigh flap.

Oral cavity reconstruction after removal of locally advanced tumors is particularly difficult because anatomical restoration must accurately reproduce the original structure and enable effective and fast rehabilitation of mastication, swallowing, and phonation. The authors report their 2-year experience with 17 patients surgically treated for oral cavity cancer with reconstruction performed with the free anterolateral thigh flap. Thanks to its thinness and pliability, this flap has proven to be perfectly adaptable to the structural peculiarities of the resected areas and has enabled the authors to considerably reduce the cosmetic and functional complications in the donor area observed with other flaps (such as the radial forearm flap). Flap grafting has always been complete and regular, and no intraoperative and postoperative complications have been observed. Swallowing recovery has always been satisfactory. On the basis of the authors' results, their current approach to oral cavity reconstruction is based on the use of flaps that enable anatomical restoration of the resected areas and reduce morbidity of the donor site. They believe that the anterolateral thigh flap can offer all of these opportunities, and the surgery can be simultaneously performed by two surgical teams.     

Vascular anatomy of the anterolateral thigh flap

Arterial and venous anatomy and their relation to the anterolateral thigh flap were examined in 10 specimens of six fresh cadavers in which radiopaque materials were injected into both the arterial and venous systems. Territories and positions of individual perforating arteries were measured, and the venous drainage pathway of the flap was analyzed. All specimens were radiographed stereoscopically to observe the three-dimensional structure of the arteries and veins. The territory of each perforating artery was smaller than expected. Most of the venous blood that had perfused the dermis was considered to pool in a polygonal venous network located in the skin layer and to enter the descending branch of the lateral circumflex femoral artery through large descending veins. The venous territories were considered different from the arterial territories. The findings in this study suggest that the design of the anterolateral thigh flap should be based on the venous architecture rather than on the arterial architecture and that the flap survival rate might be improved if thinning is performed appropriately.     

Free anterolateral thigh adipofascial perforator flap

The anterolateral thigh adipofascial flap is a vascularized flap prepared from the adipofascial layer of the anterolateral thigh region. It is a perforator flap based on septocutaneous or musculocutaneous perforators of the lateral circumflex femoral system. With methods similar to those used for the free anterolateral thigh flap, only the deep fascia of the anterolateral thigh and a 2-mm-thick to 3-mm-thick layer of subcutaneous fatty tissue above the fascia were harvested. In 11 cases, this flap (length, 5 to 11 cm; width, 4 to 8 cm) was used for successful reconstruction of extremity defects. Split-thickness skin grafts were used to immediately resurface the adipofascial flaps for eight patients, and delayed skin grafting was performed for the other three patients. The advantage of the anterolateral thigh adipofascial flap is its ability to provide vascularized, thin, pliable, gliding coverage. In addition, the donor-site defect can be closed directly. Other advantages of this flap, such as safe elevation, a long wide vascular pedicle, a large flap territory, and flow-through properties that allow simultaneous reconstruction of major-vessel and soft-tissue defects, are the same as for the conventional anterolateral thigh flap. The main disadvantage of this procedure is the need for a skin graft, with the possible complications of subsequent skin graft loss or hyperpigmentation.     

Simple approach to harvest of the anterolateral thigh flap

The free anterolateral thigh flap has proven to be invaluable for many types of reconstruction, ranging from upper and lower extremity trauma to head and neck reconstruction. There exist some controversies relating to certain difficulties in flap harvest because of the intramuscular route of its major perforator, which can exceed 80 percent and create a longer, more tedious dissection. Strategies to expedite flap harvest and minimize technical challenges have been proposed. The authors propose a simplified approach to harvest the anterolateral thigh flap founded on topographic surface anatomy and the intrinsic vascular anatomy of the flap. No Doppler imaging or angiography is used for preoperative perforator mapping.