Reconstruction of Complex Orofacial Defects: A Preliminary Experience with Composite Tissue Flaps Based on the Anterolateral Thigh Flap

Summary

This study details the synergistic combinations of the versatile anterolateral thigh flap with other flaps (pectoralis major, fibular, auricular, bilateral anterolateral thigh) for reconstructing extensive orofacial defects. We present a clinical framework that emphasizes anatomical design, surgical technique, and functional-aesthetic integration to facilitate reconstruction in severe cases.

Abstract

This study presents a systematic summary of composite tissue flap reconstruction strategies centered on the versatile anterolateral thigh (ALT) flap for complex orofacial defects. Through a retrospective analysis of 21 patients (mean age 56.4 years) at a single center, it details the rationale, surgical protocol, and outcomes of four synergistic flap combinations. These include: 1) ALT with pectoralis major myocutaneous flap for large oropharyngeal-cervical through-and-through defects; 2) ALT with fibular osteomyocutaneous flap for composite mandibular and soft tissue defects; 3) ALT with free auricular composite flap for combined large soft tissue and specialized subunit (e.g., alar rim) defects; and 4) double ALT flaps for extensive, three-dimensionally complex soft tissue defects. The procedural framework elaborates on precise indication selection, anatomical design based on perforator mapping, meticulous sequential flap harvest via standardized approaches, and key technical aspects of microvascular anastomosis. Representative results from the cohort demonstrated a 100% flap survival rate. Postoperative complications were manageable (9.5%), including one orocutaneous fistula and one donor-site seroma, neither compromising final outcomes. The findings establish a practical, individualized clinical framework that integrates reliable surgical techniques with functional-aesthetic goals, offering a practical and adaptable approach for the precise reconstruction of severe, multifaceted orofacial defects.

Introduction

With the advancement of microvascular anastomosis techniques, free flap transplantation has become a critical method for reconstructing oral and maxillofacial defects^1,2. Among various free flap options, the anterolateral thigh (ALT) flap has emerged as a commonly used choice for head and neck reconstruction due to its notable anatomical and functional advantages³.

The advantages of this flap are mainly reflected in the following aspects: first, it provides ample soft tissue volume and can be flexibly prepared as a muscle island to fill dead space or as a fat flap to repair concave defects⁴; second, its "single-pedicle multi-island" design allows for the simultaneous preparation of multiple perforator flaps, enabling precise reconstruction of complex through-and-through defects^5,6; furthermore, by harvesting tissues from different regions, flaps of varying thicknesses—from thin to thick—can be obtained, thereby avoiding bulkiness in the reconstructed area⁷. In addition, the ALT flap offers advantages such as a concealed donor site, the ability to primarily close most donor-site wounds, and a long vascular pedicle that facilitates anastomosis to contralateral neck vessels⁸, significantly enhancing the feasibility and safety of the procedure.

Although the ALT flap is suitable for reconstructing most oral and maxillofacial defects, it often needs to be combined with other flaps for complex composite defects involving multiple tissue types, large-scale areas, or specialized functional subunits. The ALT flap serves as a versatile cornerstone in complex maxillofacial reconstruction. Its synergistic combination with other flaps—such as the pectoralis major myocutaneous, fibular osteomyocutaneous, and auricular composite flaps—allows for tailored repair based on specific defect requirements, including the need for bony support, precise contour restoration, or functional reconstruction. This study aimed to systematically summarize ALT flap-based combined reconstruction strategies, thereby providing a structured surgical framework to guide the individualized, functional reconstruction of complex maxillofacial defects.

Protocol

A retrospective study was conducted involving 21 patients with complex maxillofacial defects who underwent reconstruction at the Second Xiangya Hospital of Central South University from January 2005 to December 2025. All patients received simultaneous reconstruction using the anterolateral thigh free flap as the primary component, combined with additional flap types. The study protocol received approval from the Ethics Committee of the Second Xiangya Hospital of Central South University (Approval No. 2020030), and written consent for publication of clinical photographs was obtained from all participants

1. Preoperative planning and patient preparation

1. Preoperative assessment and marking
   1. Perform preoperative handheld Doppler ultrasound mapping of perforators in the anterolateral thigh region to guide intraoperative decision-making. Mark the following surface landmarks: 1) the estimated skin paddle territory; 2) the surface projection line connecting the anterior superior iliac spine and the superolateral border of the patella.
2. Patient positioning and anesthesia
   1. Position the patient supine. Place a soft bump under the ipsilateral buttock to internally rotate the donor thigh moderately, adequately exposing its anteromedial aspect to facilitate the medial approach. Simultaneously prepare and drape both the donor site and the head and neck recipient site.
   2. Perform general anesthesia with endotracheal intubation. Establish secure intravenous access. Administer routine prophylactic antibiotics 30 min preoperatively.
3. Recipient vessel preparation in the head and neck
   1. While the flap is being harvested, a second surgical team prepares the recipient site. Perform meticulous dissection in the submandibular/cervical region to isolate suitable recipient arteries and veins.
      1. Arterial preparation:​ The superior thyroid artery is the preferred recipient artery. Dissect it to an adequate length, ensuring satisfactory caliber and vascular wall integrity.
      2. Venous preparation:​ Prepare at least two recipient veins. Typically, select a major tributary of the internal jugular vein (e.g., the common facial vein) and the main trunk of the external jugular vein. Assess their patency, length after mobilization, and size match with the flap veins.
   2. After applying clamps proximal and distal to the planned anastomotic sites, divide the vessels. Irrigate the lumens with heparinized saline and set them aside for anastomosis.
4. Microvascular anastomosis technique
   1. Following complete flap elevation and recipient site preparation, temporarily inset the flap into the defect to confirm pedicle length, orientation, and the absence of torsion or tension at the planned anastomotic sites.
   2. Perform vascular anastomoses under an operating microscope (5x magnification). The conventional sequence is " artery first, then vein."
      1. Arterial anastomosis:​ Perform an end-to-end anastomosis between the descending branch of the lateral circumflex femoral artery (or its main trunk) and the superior thyroid artery​ using 8-0 polypropylene sutures.
      2. Venous anastomosis:​ Prioritize end-to-end anastomosis between a larger concomitant vein of the flap and the tributary of the internal jugular vein. Interrupted sutures with 8-0 polypropylene sutures are recommended. Establish a second venous anastomosis between another flap vein and the external jugular vein​ (end-to-end or end-to-side) to create dual venous drainage.
         NOTE:​ Ensure adequate adventitial trimming, precise intima-to-intima coaptation, and even suture spacing and bite depth. Irrigate the lumens with heparinized saline before completing the anastomoses. Release the clamps sequentially (vein then artery) and confirm immediate flap reperfusion evidenced by rapid blush, active bleeding from the edges, and prompt capillary refill.
5. Postoperative flap monitoring
   1. Transfer the patient to a monitored care unit postoperatively and implement a standardized monitoring protocol. The first 24–48 h are critical; assess the flap hourly​ for color, temperature, capillary refill time, and degree of swelling (turgor). Consider the following to be warning signs:​ Darkening or pallor, a temperature drop of >2 °C compared to adjacent tissue, capillary refill time >3 s or absent, and progressive swelling are suggestive of vascular compromise.
      NOTE: A temperature monitoring probe may be used adjunctively.
6. Management principle
   1. If vascular compromise is suspected, after ruling out external compression, prompt surgical re-exploration is indicated. Concurrently, maintain patient normothermia, stable blood pressure, and adequate circulating volume. Administer anticoagulant and antispasmodic medications as prescribed.

2. Flap harvesting techniques

1. Anterolateral thigh (ALT) flap harvesting
   1. ​ Harvest the flap via a medial approach. Mark the skin line from the anterior superior iliac spine to the superolateral patella, denoting the surface projection of the intermuscular septum between the rectus femoris and vastus lateralis muscles; perforators are typically found along or lateral to this line.
   2. ​ Make a parallel incision 2 cm medial to this line. Identify suitable perforators. For an anteromedial thigh perforator, confirm its origin from the descending branch of the lateral circumflex femoral artery by dissection through the rectus femoris. Trace the selected perforator retrograde to its main trunk.
   3. ​ In the intermuscular space between the rectus femoris and vastus lateralis, isolate the descending and transverse branches of the lateral circumflex femoral vessels to complete the pedicle dissection.
2. Fibular osteomyocutaneous flap harvesting
   1. For fibular flap harvesting, mark​ the fibular head and lateral malleolus. Outline​ the surface projection line of the intermuscular septum between the soleus and peroneus longus muscles, an area where perforating vessels are typically located.
   2. Following this, make​ a longitudinal incision approximately 1 cm medial to and parallel with this projection line. Following layered dissection, identify​ and confirm​ the septocutaneous or musculocutaneous perforators from the peroneal vessels. Incise​ the attachments of the peroneus longus and brevis muscles to the lateral border of the fibula, preserving a 2–3 mm muscle cuff.
   3. Subsequently, divide​ the extensor digitorum longus, hallucis longus muscles, and the interosseous membrane anterior to the fibula. Retract​ the fibular segment anteriorly, and dissect​ the peroneal vascular pedicle meticulously from proximal to distal, ligating its muscular branches. Detach​ the flexor hallucis longus muscle from the posterior aspect of the fibula while preserving a portion of its cuff to protect the vascular bundle. Finally, osteotomize​ the fibula to the required length.
3. Pectoralis major myocutaneous flap harvesting
   1. Begin the harvesting of the pectoralis major myocutaneous flap by marking​ a line from the midpoint of the clavicle to the xiphoid process, representing the surface projection of the pectoral branch of the thoracoacromial artery. Design​ a skin island along this axis, typically within an area extending from 4–6 cm below the clavicle to the superior aspect of the xiphoid.
   2. Incise​ the superior and lateral margins of the skin island, and suture​ the skin edges to the underlying muscle fascia to prevent shearing. Proceed​ with dissection from inferolateral to superomedial in the plane deep to the pectoralis major muscle.
   3. Identify​ and preserve​ the pectoral branch of the thoracoacromial artery and its venae comitantes within the space between the pectoralis major and minor muscles. To achieve the necessary pedicle length and arc of rotation, partially divide​ the clavicular and sternal origins of the pectoralis major as needed, thus creating a myocutaneous flap based on this neurovascular pedicle.
   4. Transpose​ the flap to the head and neck recipient site via a supraclavicular or infraclavicular tunnel under no tension. After inset, close​ the donor site in layers following meticulous hemostasis.
4. Auricular composite flap harvesting
   1. Begin the harvesting of the free auricular composite flap​ with preoperative Doppler ultrasonography to map the superficial temporal artery and its preauricular branches anterior to the ear. Design​ a composite flap encompassing skin and auricular cartilage, centering on the concha or crus of the helix, according to the recipient defect's morphology. Incise​ the marked skin, subcutaneous tissue, and perichondrium.
   2. Dissect​ the vascular pedicle (superficial temporal vessels) proximally in the preauricular region to obtain sufficient length and caliber. Elevate​ the full-thickness composite flap, consisting of skin and cartilage, sharply in the subperichondrial plane, maintaining the anatomical continuity between the cartilage and its overlying skin paddle. Following complete mobilization, divide​ the vascular pedicle, and transfer​ the flap. Close​ the donor site primarily after adequate mobilization, with careful reshaping of the auricular contour.

3. Key technical execution strategies for consecutive flap reconstruction

1. Fibular (osteomyocutaneous) flap + ALT flap
   1. Use this combination for simultaneous reconstruction of large mandibular defects with extensive intra-oral and/or extra-oral soft tissue loss. Perform arterial and venous anastomoses of the fibular flap first to establish perfusion to the bony framework, followed by rigid fixation. Subsequently, anastomose the vascular pedicle of the ALT flap to the distal end of the fibular flap vessels or to a separate set of recipient vessels. Position and inset the ALT flap to achieve optimal soft tissue coverage and contour.
2. Pectoralis major myocutaneous flap + ALT flap
   1. Use this combination for large oropharyngeal-cervical through-and-through defects. Position the pedicled pectoralis major myocutaneous flap to reconstruct the intra-oral mucosal defect and isolate the oropharyngeal cavity. Subsequently, inset the free ALT flap to reconstruct the external cervicofacial defect and/or provide additional soft tissue volume.
3. ALT flap + free auricular composite flap
   1. Use this approach for defects requiring reconstruction of extensive soft tissue together with a small, specialized three-dimensional facial subunit (e.g., alar rim). First, anastomose the ALT flap pedicle to the primary recipient vessels. Then, anastomose the auricular composite flap pedicle (e.g., 0.8–1.5 mm diameter) to a distal perforator or side branch of the ALT flap pedicle. Inset each flap independently to achieve optimal three-dimensional reconstruction without requiring additional recipient vessels.
4. Double ALT flaps
   1. Use this approach for extensive, three-dimensionally complex soft tissue defects requiring large-volume reconstruction. Harvest two independent ALT flaps from bilateral thighs. Perform microvascular anastomosis of one flap to the primary recipient vessels. Subsequently, anastomose the second flap to the distal end or a branch of the first flap pedicle. Inset the flaps separately to reconstruct intra-oral and extra-oral components or different three-dimensional planes.

[Place Figure 1234 here]

4. Standardized protocol for local wound care

1. Cleanse the wound and surrounding periwound skin with sterile normal saline.
2. Apply povidone-iodine solution to achieve antisepsis.
3. Insert iodoform gauze into the wound tract as a wick to facilitate drainage. Cover the site with a sterile gauze outer dressing.
4. Repeat steps 4.1–4.3 once to twice daily until the wound is completely dry and epithelialized.
5. Monitor the drainage regularly for character, color, and volume.
6. Assess the wound site for signs of infection, including erythema, increased local temperature, and worsening pain.

Results

Study participants and flap selection
This study included 21 male patients with composite tissue defects resulting from radical resection of oral and maxillofacial tumors. The mean age was 56.4 years (range: 48–65 years). The reconstructive strategy employed personalized combinations of flaps based on the defect's location, extent, and functional requirements: 14 patients underwent reconstruction with a fibular osteomyocutaneous flap combined with an anterolateral thigh (ALT) flap for simultaneous ma...

Discussion

In this study, the consecutive use of multiple flaps centered around the ALT flap is presented as a set of reproducible technical strategies rather than a comparative clinical series. The representative cases illustrate how these configurations can be applied across different defect patterns, emphasizing procedural feasibility, flap integration, and reconstructive flexibility rather than comparative outcome superiority.

Versatility of the anterolateral thigh flap as a reconstructive co...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
curved scissors	Shuanglu Medical	SL0014	used for sharp dissection of soft tissues
curved hemostat	Shuanglu Medical	SL0006	used for grasping and clamping larger vessels and tissue bundles.
curved mosquito hemostat	Shuanglu Medical	SL002S	used for precise clamping of delicate vessels and hemostasis in confined spaces.
cefperazone-Sulbactam	Harbin Pharmaceutical Group Co., Ltd	H19980085	used for perioperative antimicrobial prophylaxis to prevent surgical site infection.
doppler ultrasound	Bestman	BV-520T	used for preoperative perforator mapping and postoperative flap perfusion assessment.
low molecular heparin	Nanjing King-Friend	H20153092	used for  anticoagulation prophylaxis to prevent thrombosis.
micro forceps	Jinzhong surgical instrument	WCC010	used for handling delicate vessels and nerves during microsurgery.
micro needle Holders	Jinzhong surgical instrument	WBA350	used for performing microvascular anastomosis with fine sutures.
micro scissors	Jinzhong surgical instrument	WA1030	used for microvascular dissection and trimming of vessels ends.
micro sutures	Johnson	W2777	used for performing microvascular arterial and venous anastomoses.
needle holders	Shuanglu Medical	SL0035	used for suturing soft tissues and wound closure.
oscillating saw or piezoelectric system	Aesculap	GD670	used for performing precise bone osteotomies
scalpel handle	Shuanglu Medical	SL0075	used for making skin and tissue incisions.
surgical drain	Bainus	A-100	used for postoperative fluid evacuation
suture	Ethicon	VCP311H	used for soft tissue approximation and wound closure.
temperature monitoring probe	Med-linket	W0004LS	used for continuous postoperative monitoring of flap skin temperature.
tissue retractor	Jinzhong surgical instrument	J50130	used for exposure of the surgical field and tissue retraction.
titanium reconstruction plates and screws	Biomet Microfixation	44-1018	used for bridging and rigid fixation of mandibular used for performing precise bone osteotomies.
vascular clamps	KingSung Medical	KCMASB	used for temporary occlusion of vessels during anastomosis.