ALT flap presentation.pptx

Anterolateral thigh flap

1. Anterolateral thigh (ALT) flap

2. Introduction The anterolateral thigh (ALT) free flap was first described by Song et al. in 1984 as a soft tissue flap that is perfused by septo -cutaneous branches of the lateral circumflex femoral artery (LCFA). It is a Fasciocutaneous flap (type B – S epto -cutaneous perforator) or ( type C - musculocutaneous perforator )

3. Work horse flap for reconstruction As a Pedicled flap Distally based (on distal minor pedicle) – for knee defect Proximally based –Trochanteric bed sore, Lower abdominal defects Perineal reconstruction , Gluteal defect. As a Free Flap  Buccal mucosa defect ,Buccal through & through defect , Pharyngo-oesophageal reconstruction ,Lower lip ,Lateral & anterior skull base, Scalp defects , breast reconstruction , Extremity reconstruction , Phalloplasty etc.

4. Flap supply ALT flap is supplied by either septocutaneaus vessels (87%) or musculocutaneaus perforators (13%) from the descending branch of LCFA. Length : 12 cm (range 8-16 cm ) Diameter : 2.1 mm (range 2-2.5 mm) Two venae comitantes accompanies the pedicle Lateral femoral cutaneous nerve (L2-L3) provide the sensory innervation to the area

5. Pre-op Evaluation Functional evaluation of knee extension Previous scar that may affect flap design Marking of perforator by Doppler Prior skin graft donor sites can be incorporated as part of the flap

6. Important landmark ASIS and superior lateral border of patella Perforators are located at this drawn line The ASIS to lateral patella ( Septocutaneus ) Posterior to this line ( Musculocutaneaus )

7. Flap harvest Medial incision first and subfascial approach. Rectus femoris is identified by its bipinnate arrangement of fibers around central raphe. Septum is identified between RF and VL. By doing medial retraction , Any Septo -cutaneous Perforator should be visualized by now.

8. If No perforator is visualized the deep fascia should be dissected off the VL. And still no perforator is visualized incision can be extended superiorly or inferiorly to search for a perforator. When the perforator is found ,then only the dissection proceeds. The perforator is dissected to its source pedicle .

9. All Possible nerves to vastus lateralis and the muscle itself should be preserved. Once the anterior dissection is complete ,lateral incision can be taken.

10. Flap modification Thin Flap Adipofascial flap Innervated flap Functional muscle flap Flow through flap Chimeric

11. Advantages Disadvantages Ease of harvest Colour mismatch in facial reconstruction Long length and large pedicle Presence of hairs in male patients Versality in design Skin graft at donor site (>8cm width of the flap) Ablity to provide sensory innervation Excess flap bulk required secondary de-bulking Less donor site morbidity Fistula and stricture in pharyngeal reconstruction Less operative time with two team approach Breast reconstruction- fat necrosis

12. Clinical examples

13. Pedicled ALT flap cover Proximally based and distally based for Trochantric sore and knee defect

14. Thank you