Background
Complex perineal defects pose major reconstructive challenges due to dead space, three-dimensional tissue loss, and the need to preserve function. The pedicled anterolateral thigh (ALT) flap is a versatile option that offers reliable vascularity, substantial soft-tissue bulk, low donor-site morbidity, and the ability to achieve composite designs when additional muscle or fascial support is required. Its reconstructive reach extends beyond the perineum, perianal region, and abdomen, and in our experience may reach above the umbilicus when length-maximising manoeuvres are used.
Method
This presentation focuses on the operative technique of pedicled ALT flap reconstruction for complex perineal and abdominal defects. The key steps are preoperative perforator mapping, flap design tailored to defect geometry, and proximal pedicle dissection to maximise arc of rotation.
Technical refinements to increase reach include creation of a sub-rectus femoris tunnel, selective ligation of the rectus femoris vascular leash, and development of a wide subcutaneous tunnel commencing medial to the rectus femoris. The sartorius may be vented or divided to prevent a point of mechanical tension on the flap pedicle. Additional principles include avoiding acute pedicle angulation and performing an inset without tension or compression.
In our experience, these manoeuvres provide additional reach sufficient for transfer into the perineum, pelvis, and abdomen, including above the umbilicus. Composite modification with vastus lateralis or fascia lata may be used selectively to improve bulk, obliterate dead space, reconstruct pelvic floor support, or restore abdominal wall integrity. Representative cases will demonstrate practical decision-making, flap customisation, and technical refinements in real-world reconstruction.
Conclusion
The pedicled ALT flap is a powerful reconstructive option for complex perineal and selected abdominal defects. A structured approach to pedicle length optimisation, tunnel creation, and inset can extend reach, improve reliability, and broaden reconstructive options for demanding pelvic and perineal defects.