Anterolateral thigh flap

Anatomy

Septocutaneous perforators of descending branch of the lateral circumflex femoral artery enter the fascia between the lateral border of the rectus femoris and medial border of vastus lateralis. Length of pedicle: 12cm, diameter 2mm.

Perforator found one third of the way between the ASIS and the superolateral border of the patella. Pre op doppler should be performed.

Minor pedicles arise from musculocutanous perforators of LCFA and musculocutaneous branch of transverse branch of LCFA

Size: 12x20cm, from a point 10cm below ASIS to 7cm above the patella. Medial border is medial border of rectus femoris and lateral border is the lateral intermuscular septum between TFL, vastus lateralis and biceps femoris.

Nerve supply: lateral cutaneous nerve of the thigh

Modifications

Tissue expansion to increase size and improve donor site primary closure possibility.

TFL may be included using the transverse branch of the LFCA

Flap elevation

Medial border incised down to deep fascia. Fascia elevated until identification of lateral border of rectus femoris. Perforator identified. Posterior border of flap incised and followed to perforator.

References

Koshima I, Fukuda H, Utumomiya R, Soeda S. The anterolateral thigh flap: Variations in its vascular pedicle. Br J Plast Surg 42:260,1989.

Based on dissections performed in 13 patients to elevate an anterior lateral thigh flap, the authors describe the flap vascular anatomy and its variations. In three patients the septocutaneous perforator originated from the descending branch of the lateral circumflex femoral artery (type 1). In five patients the pedicle originated directly from the profunda femoris artery (type II). In the remaining five patients no septocutaneous pedicle was visualized. In these patients flap dissection was converted to either a free tensor fascia lata (3) or an anterior medial thigh (2) flap. Despite the variability in pedicle origin, the authors find the flap useful for covering thin defects in mobile areas while leaving a flap donor site that is acceptable to patients.

Pa-Chuen X, Shi-Zhen Z, Ji-Ming K, Guo Ying W, Muzhi L, Li-Sheng L, Jian-Hua G. Applied anatomy of the anterior lateral femoral flap. Plast Reconstr Surg 82:305, 1988.

This study of flap anatomy is based on a Doppler analysis of 50 volunteer adults and cadaver dissections in 42 legs; vascular injection techniques were used in 35 cadavers. The surface projection of the lateral circumflex femoral artery is located along a line between the midpoint of the inguinal ligament and the midpoint of a line between the anterior superior iliac spine and the lateral border of the patella. The descending branch of the lateral circumflex femoral artery is identified as the flap vascular pedicle based on penetrating branches of musculocutaneous pedicles (59.2%) or direct branches in the musculoseptal pedicles (40.8%). Proximal dissection of the descending branch of the lateral femoral circumflex artery and associated venae comitantes provides a pedicle length of 8 to 12 cm. In 92 % of patients an audible pedicle located within a 3 cm radius in the midpoint of a line connecting the anterior superior iliac spine and the lateral border of the patella was identified using the Doppler probe. Injection of the pedicle with latex in cadaver dissections demonstrated a cutaneous territory of 12 X 30 cm. The lateral femoral cutaneous nerve may be used if a sensory flap is required. In addition to representing a useful donor site for free flap design, the authors note the potential usefulness of the anterior lateral thigh flap as an island transposition flap for lower abdomen and gluteal regions.

Song YG, Chen GZ, Song YL. The free thigh flap: A new free flap concept based on the septocutaneous artery. BrJ Plast Surg 37:149, 1984.

The authors describe three donor sites on the thigh for design of fasciocutaneous flaps for microvascular transplantation. Each flap is based on a subcutaneous pedicle. Anatomy, operative technique, and flap characteristics are discussed. The anterior lateral thigh flap is based on the cutaneous branch of the descending branch of the lateral circumflex femoral artery and associated venae comitantes with the pedicle entering the thigh fascia between the rectos femoris and vastus lateralis muscles at the junction of the proximal and middle third of the leg. The anterior medial thigh flap is based on the cutaneous branch of the innominate descending branch of the lateral circumflex femoral artery. This pedicle enters the thigh fascia between the rectos femoris and the vastus medialis muscles at the lateral edge of the sartorius muscle in the midthigh. The posterior thigh flap is based on one of the four perforating arteries from the profunda femoris supplying skin and muscles in the posterior lateral thigh. The third perforating artery enters the thigh fascia between the vastus lateralis and biceps femoris muscles. Of the 15 free thigh flaps used for reconstruction of head and neck burn contractures, the flap design was as follows: anterolateral (9), anteromedial (4), and posterior (2) thigh.

Koshima I, Fukuda H, Yamamoto H, Moriguchi T, Soeda S, Ohta S. Free anterolateral thigh flap for reconstruction of head and neck defects. Plast Reconstr Surg 92:421, 1993.

The anterior lateral thigh flap was successfully used in 22 patients for scalp defects (2) and intraoral or extraoral esophageal or cervical defects (20). The size of the flaps ranged from 8 to 25 cm in length and 4 to 18 cm in width. Four variations in the origin of the vascular pedicle were observed: descending branch of the lateral circumflex femoral system, transverse branch, directly from the profunda femoris artery, and musculocutaneous perforators from the lateral circumflex femoral system. This flap is compared with vascularized intestinal interposition, radial forearm, and rectos abdominis musculocutaneous flaps for use in head and neck reconstruction.

Thou G, Qiao Q, Chen GY, Ling YC, Swift R. Clinical experience in surgical anatomy of 32 free anterior lateral thigh flap transplantations. Br J Plast Surg 44:91, 1991.

The anterior lateral thigh flap was successfully transplanted as a free flap in 32 patients with the following defect distribution: hands or face and forehead (5), burn scars (10), Rhomberg's hemifacial atrophy (6), first and second branchial arch hypoplasia (6), and trauma (5). Recipient sites were as follows: scalp and face (18), hand (2), neck (S), dorsum of foot (3), and plantar foot (4). The authors note three patterns of origin of the vascular pedicle: (1) direct fasciocutaneous pedicle (37.5%), (2) vertical musculocutaneous perforators from the descending branch of the lateral circumflex femoral artery (56.2%), and horizontal musculocutaneous perforator from the transverse branch of the lateral circumflex femoral artery (6.3 %). The exit point of the vascular pedicle from the intermuscular septum or vastus lateralis muscle is consistent in its location 2 cm lateral and inferior to the midpoint of a line joining the anterior superior iliac spine and the lateral border of the patella. Fascia lata is routinely included in the flap design. The exit point is generally located with a Doppler probe prior to flap design. Although the cutaneous perforator is small at the point of exit through the septum or vastus lateralis muscle, it reliably supports a flap design with the superior margin at the level of the distal end of the tensor fascia lata muscle and the lower border 7 cm above the patella. The medial border is located at the medial edge of the rectos femoris muscle and the lateral border is located at the lateral intramuscular septum.