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.     

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.     

Free filet extremity flap: indications and options for reconstruction

Radical and extended forequarter and hind limb amputations have been used for curative and palliative intents. Concerns regarding wound healing and closure, especially in irradiated fields, have occasionally limited the extent of ablation. This article reports an experience with coverage of these large defects by using the free filet extremity flap. A retrospective review was performed of 11 patients who had undergone immediate reconstruction with free filet extremity flaps between 1991 and 1998. There were nine men and two women with an average age of 43.9 years. All except three patients received preoperative radiotherapy. Resections included four hindquarter and seven forequarter amputations for palliation of intractable pain, tissue necrosis, and infections. Donor vessels included the brachial artery, its venae comitantes, cephalic and basilic veins, and common femoral and popliteal vessels. Immediate reconstruction was successful in all cases by the use of the amputated limb as the free filet flap. All wounds healed despite irradiation inclusive of defects up to 50 cm x 70 cm (3500 cm2). The average follow-up time was 5 months with a mean survival of 3.5 months. Four patients currently are alive, and one patient died within 30 days of surgery. The remaining six patients have died of their disease within 9 months of the palliative procedures. Pain, tissue necrosis, and infections were improved in all patients after hospital discharge. Extensive defects can be reconstructed and healed successfully, even in irradiated wounds, with the use of the free filet extremity flap. Appropriate advanced preoperative and intraoperative planning is essential. Although survival was unchanged, this technique allowed healed wounds with an improvement in the quality of life.     

The innervated anterolateral thigh flap: anatomical study and clinical implications

During the past 20 years, the neural anatomy of many flaps has been investigated, although no extensive studies have been reported yet on the anterolateral thigh flap. The goal of this study was to describe the sensory territories of the nerves supplying the anterolateral thigh flap with dissections on fresh cadavers and with local anesthetic injections in living subjects. The sensate anterolateral thigh flap is typically described as innervated by the lateral cutaneous femoral nerve. Two other well-known nerves, the superior perforator nerve and the median perforator nerve, which enter the flap at its medial border, might have a role in anterolateral thigh flap innervation. Twenty-nine anterolateral thigh flaps were elevated in 15 cadavers, and the lateral cutaneous femoral nerve, the superior perforator nerve, and median perforator nerve were dissected. In the injection study, the lateral cutaneous femoral nerve, superior perforator nerve, and median perforator nerve in 16 thighs of eight subjects were sequentially blocked. The resulting sensory deficit from each injection was mapped on the skin and superimposed on the marked anterolateral thigh flap territory. The study shows that the sensate anterolateral thigh flap is basically innervated by all three nerves. The lateral cutaneous femoral nerve was present in 29 of 29 thighs, whereas the superior perforator nerve was present in 25 of 29 and the median perforator nerve in 24 of 29 thighs. Furthermore, in the proximal half of the flap, the lateral cutaneous femoral nerve lies deep, whereas the superior perforator nerve and median perforator nerve lie more superficially. Whereas the lateral cutaneous femoral nerve innervates the entire flap, the superior perforator nerve innervates 25 percent of the flap and the median perforator nerve innervates 60 percent of the flap. Clinically, a small anterolateral thigh flap (7 x 5 cm) can be raised sparing the lateral cutaneous femoral nerve and using only the selective areas innervated by the superior perforator and median perforator nerves. Alternatively, a large anterolateral thigh flap can be raised with this multiple innervation. This can be helpful if one wants to harvest the flap under local anesthesia. Sensate bilobed flaps can be harvested when dual innervated flaps are required.     

Distally based anterolateral thigh flap: an anatomic and clinical study

The distally based anterolateral thigh flap has been used for coverage of soft-tissue defects of the knee and upper third of the leg. This flap is based on the septocutaneous or musculocutaneous perforators derived from the lateral circumflex femoral system. The purpose of this study was to examine the results of anatomical variations of the descending branch of the lateral circumflex femoral artery and the retrograde blood pressure of the descending branch of the lateral circumflex femoral artery so that the surgical technique for raising and transferring a distally based anterolateral thigh flap to the knee region could be improved. The authors have actually used this flap in three cases. In 11 thighs of six cadavers, the descending branch of the lateral circumflex femoral artery had a rather consistent connection with the lateral superior genicular artery or profunda femoral artery in the knee region. The pivot point, located at the distal portion of the vastus lateralis muscle, ranges from 3 to 10 cm above the knee. In their three cases, the maximal flap size was 7.0 x 16.0 cm and was harvested safely, without marginal necrosis. The mean pedicle length was 15.2 +/- 0.7 cm (range, 14.5 to 16 cm). The average proximal and distal retrograde blood pressure of the descending branch of the lateral circumflex femoral artery was also studied in another 11 patients, and the anterolateral thigh flap being used for reconstruction of head and neck defects showed 58.3 and 77.7 percent of proximal antegrade blood pressure, respectively. The advantages of this flap include a long pedicle length, a sufficient tissue supply, possible combination with fascia lata for tendon reconstruction, and favorable donor-site selection, without sacrifice of major vessels or muscles.     

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.     

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.     

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.