CLINICAL REVIEW David W. Eisele, MD, Section Editor ANTEROLATERAL THIGH FLAP Chin-Ho Wong, MBBS, MRCS, MMed (Surgery), FAMS (Plast. Surg.), 1 Fu-Chan Wei, MD 2 1 Department of Plastic Reconstructive and Aesthetic Surgery, Singapore General Hospital, Outram Road, 169608, Singapore. E-mail: wchinho@hotmail.com 2 Department of Plastic Surgery, Chang Gung Memorial Hospital and Medical College, Chang Gung University, Taoyuan, Taiwan Accepted 29 May 2009 Published online 11 August 2009 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/hed.21204 Abstract: The anterolateral thigh (ALT) flap is a versatile soft tissue flap. It can be harvested as a fasciocutaneous or myo- cutaneous flap. Vascularized fascia can be included or the pedi- cle may be harvested as a flow-through flap. The flap can also be harvested incorporating multiple skin islands or as a chimeric flap incorporating separate skin and muscle components. When a large flap is needed, the entire lateral thigh can be harvested by combining the ALT with either the tensor fascia lata or the anteromedial thigh flap as a conjoined flap. Morbidity is remark- ably minimal despite the availability of such generous amounts of tissue. The purported difficulty with the use of this flap is because of the anatomical variations that may render this flap unreliable. This paper clarifies the vascular anatomy of the flap and elaborates an approach to flap harvest that can be used to reliably harvest the flap in spite of the anomalies that may be encountered. V V C 2009 Wiley Periodicals, Inc. Head Neck 32: 529–540, 2010 Keywords: ALT; flap; harvest; approach; safety; anatomy; oblique branch; anomaly; soft tissue flap; versatility The anterolateral thigh (ALT) flap was first described by Song et al 1 in 1984 as a flap based on septocutaneous vessels running in between the rectus femoris and vastus lateralis muscles. However, it was soon noted that septocutaneous vessels were present only in a minority of cases. The majority of the vessels supplying the flap are musculocutaneous perforators traversing the vastus lateralis muscle. 2–4 Intramuscular dissection was considered unsafe and ill-advised in 1984. Koshima et al, 2 in his early series, noted that this flap was unusable in 5 of 13 cases because of absent septocutaneous vessels. The flap thus gained a reputation of being unus- able in a significant proportion of patients. With the development and maturation of perforator flaps, the technique of intramuscular perforator dissection gradually became widely used. The ALT perforator flap quickly gained prominence and was regarded as exemplary of perforator flaps. 5–8 Wei et al 9,10 was instrumental in popu- larizing its use and considered it an ideal soft tissue flap. With greater collective experience, the initial difficulties with this flap were gradu- ally surmounted and its advantages appreciated more and more. Despite this, its adoption remains cautious because of the so-called ana- tomic variations of its vascular anatomy for Correspondence to: C.-H. Wong The authors did not receive any funding for this work and declare no conflict of interest in this present work. V V C 2009 Wiley Periodicals, Inc. Anterolateral Thigh Flap HEAD & NECK—DOI 10.1002/hed April 2010 529