1.Dr Subhakanta Mohapatra IPGME&R,Kolkata.INDIA

2. History by Song et al 1984 - 1st introduced 1986 - for head & neck reconstruction 1st described by Koshima et al 1992 1st microvascular transfer of VL muscle flap Wolff 1995 for lower extremity defect 1996 ultrathin flap (3-4 mm) preserving subdermal plexus Kimura et al Very popular reconstructive flap in Asia Limited use in West vascular anatomy variations difficult dissection thick thigh fat 3. Indications Head & neck reconstructions Buccal mucosa defect Buccal through & through defect Pharyngo-oesophageal reconstruction Lower lip Tongue Lateral & anterior skull base Scalp Combined with free fibula flap Extremity reconstruction 4. Contraindications Previous surgeries Injury to upper thigh Morbid obesity too thick flap Difficultintramuscular dissection Severe peripheral disease 5. Types Free flap Pedicled flap Distally based (on distal minor pedicle) for knee defect Proximally based Trochanteric bed sore Lower abdominal defects Perineal reconstruction Gluteal defect 6. Types Type B/C Fasciocutaneous flap (type B - septocutaneous perforator) or ( type C - musculocutaneous perforator ) Musculocutaneous flap Fascial flap Adipo fascial flap for Romberg disease Sensate flap(include lateral femoral cutaneous nv.) Osteo fascio cutaneous flap Chimeric flap ( 2 or more separate defect) 2 small independent flaps Muscle only flap Flow through flap (to salvage extremity, where proximal & distal ends of pedicle anastomosed to recipient vessel) 7. Pre-Op preparation Exclude previous trauma/surgery to thigh Doppler study over lateral intermuscular septum 2-3 cm lateral to lateral intermuscular septum(over medial part of VL) Angiography - not helpful Check for popliteal pulsation Consent for - failure/risk/alternate (RFFF) Donor site morbidity, knee instability / limping gait No IV line in flap leg 8. Landmarks Line drawn between ASIS & supero-lateral border ofpatella Corresponds to the septum between RF & VL. Skin perforators mapped by Doppler Accuracy of Doppler decreases as BMI increases. 9. Flap dimensions Maximum length 30 cm Maximum width 15 cm For direct closure maximum width 8 - 10 cm or < 16% of thigh circumference 10. Muscles of antero lateral thigh 11. Vascular system of Anterolateral thigh & standard skin paddle 12. Standard flap design 13. Flap harvesting Initial skin incision on medial flap aspect over RF , 2-3cm medial to lateral inter-muscular septum. Proximal incision between TFL & RF Sub-fascial incision through deep fascia with lateral dissection until perforators identified Supra-fascial - for thin flap carried laterally until perforators identified 14. Flap harvesting Skin incision completed after perforator identification Retrograde dissection of pedicle to descending branch May involve dissection of VL. A cuff of muscle may be left to protect perforating branches. Advantage of taking a part of VL easy harvest no intramuscular dissection pedicle twisting will be less Lateral femoral cutaneous nerve sensate flap Thinning performed in deep fat layer to avoid pedicle injury. 15. Pedicle 1 Artery, 2 Venae commitantes, motor branch of femoral nerve to VL Based on perforators from descending branch of lateral circumflex femoral artery (90%). From transverse branch of LCFA (4%). From profunda femoris (4%) pierces through RF.Descending branch Can be safely dissected proximally to its major branch to RF, which should be preserved Runs in inter-muscular space b/w RF & VL. Terminates by anastomosing with superior lateral genicular artery. 16. Dimensions of vascular pedicle Average length of pedicle 12 cm Diameter ( DLCFA ) Artery - 1.5 2.5 mm ( Avg - 2.1 mm ) Veins 1.8 3.3 mm ( Avg - 2.3 mm ) 17. Cutaneous perforator origin 18. Perforators Mapping A (most proximal),B, C (most distal) Musculocutaneous perforator (80-90%) - traverseVL (close to medial edge) & deep fascia to supply skin Septocutaneous perforator (10-20%) runs in-between RF & VL pierces the fascia lata to supply skin 19. Perforator classification Type 1 (50 %) Perpendicularly to subdermal plexus. Type 2 (35%) Branch in adipose & extends into subdermal plexus. Type 3 (15%) Extends along deep fascia & gradually into adipose . 20. Sensory innervations Lateral femoral cutaneous nerve(L2-L3) Direct branch of lumbar plexus Enters thigh deep to IL near ASIS. Follows path of deep circumflex iliac artery & vein Lies along line connecting ASIS to lateral patella. Pierces fascia lata 10 cm distal to IL. Travels in deep subcutaneous layer immediately superficial to deep fascia. 21. ALT Flap Markings 22. Medial flap incision & septum identification 23. Opening of septum 24. Septum dissection distal to proximal 25. Medial retraction of RF & Identification of pedicle 26. Dissection of perforator & preservation of motor branches of femoral nerve 27. Final skin paddle & Readjustment 28. Medial retraction of RF & Identification of DLCFA 29. Skin incision 30. Incision of fascia 31. Exposure of vascular pedicle 32. Detachment of inter-muscular septum 33. Separation of pedicle components 34. Identification of perforator & distal ligation of pedicle 35. Circumcision of skin paddle 36. Fixation of skin paddle to muscle 37. Dissection of vascular pedicle 38. Cross section anatomy of flap 39. Flap ready for microvascular transfer 40. Myo-cutaneous flap containing 2 perforator 41. Advantages Minimal long term donor site morbidity Long,reliable,larger pedicle Large skin paddle Can cover complex wound Good pliability No major artery is sacrificed Ability to tailor the thickness of flap. 42. Disadvantages Bulky flap Hair bearing flap in male Primary closure of donor site is not possible in mostcases. 43. Post operative care Removal of drain - output < 30 ml/day, with serosanguinous discharge. Encourage to walk on 3rd post op day. 44. Post op complications Recipient site Flap necrosis Fistula (head & neckreconstruction ) Haemorrhage Arterial occlusion Local abscess Exposed bone/plateDonor site STSG loss Wound infection Dog ears Pain & weakness in thighinjury to nerve to VL. Seroma/haematoma Partial necrosis of foot & calf in a case of DLCFA act as a critical collateral for an obstructed superficial femoral artery. 45. Outcome & prognosis Minimal long term donor site complications Allowed to walk after 3 days No significant decrease in strength or range of motion 46. ALT vs Radial forearm free flap ALT Increased learning curve Primary closure Morbidity related to vastuslateralis damage Potential dysfunction Quadriceps Pain Disto-lateral thigh anaesthesia /paraesthesiaRadial forearm free flap Potential tendon exposure Sacrifice of dominantdistal blood supply Closure with STSG Potential dysfunctions Hand stiffness Pain Anaesthesia / paraesthesia 47. Anatomical Variations Absence of cutaneous perforator in 5.4 % Absence of descending branch in 22.6 %replaced by medial descending branch ( inominate branch ) Ascending branch can supply a perforator to upper part of ALT, which can be used when normal ALT perforators are inadequate Other leg can be used 48. ALT Failure Etiology Inadvertent perforator divison at fascial plane Inadvertent perforator injury during intramusculardissection Pedicle twisting during inset 49. Follow up recipient area Aesthetic Sagging of flap Hair growth on flap Contour defect Flap bulkiness need of debulking ( shoe wearing) 50. Follow up recipient area. Functional Speech problems Oral incompetence Eating problems Facial pain Nasal obstruction 51. Follow up Donor area Aesthetic Hypertrophic scar Hypo/hyper pigmentation Keloid Contour defect 52. Follow up donor site. Functional Slightly limping gait Sensory disturbances Cold intolerance 53. Controversies Anatomy unpredictable Dissection difficult Doppler identification of perforator is difficult. 54. Future Emerged as new workhouse flap for soft tissue head& neck reconstruction.