ANTERO LATERAL THIGH FLAP (ALT FLAP)

1. Dr Gautam Kalra
Senior Resident
Dept Of Plastic Surgery
AFMC
ALT – ANTERO LATERAL THIGH FLAP

2. History
⚫1984 - 1st introduced by Song et al
⚫1986 - for head & neck reconstruction 1st described by
Koshima etal

3. ANATOMY
⚫ARTERIAL SUPPLY
⚫Perforators from the descending branch of Lateral
circumflex femoral artery
⚫Can be septo-cutaneous or myo-cutaneous
perforators (13%/87%) (Ref – Wei Mardini)
⚫Pedicle length –
⚫12cm (8-16cm)
⚫Diameter – 2-2.5mm
⚫In 2% cases there may be
Absence of any skin
Perforator.

4. ANATOMY
⚫VENOUS DRAINAGE
⚫Venae commitantes of the lateral circumflex
femoral artery
⚫Length – 8-16cm diameter – 1.5 – 2.5 mm

5. FLAP INNERVATION
⚫SENSORY –
⚫Lateral femoral cutaneous nerve
⚫Sensory nerve pierce the fascia 10cm below the
inguinal ligament medial to TFL
⚫MOTOR
⚫Vastus lateralis innervated by posterior division of
femoral nerve

6. Flap dimensions
⚫Maximum length – 21cm (4-35 cm)
⚫Maximumwidth – 8 cm (4-25cm)
⚫Thickness – 5mm (3-20mm)
⚫Fordirectclosure –
maximumwidth – 8 cm
Muscle Dimensions – 2cm to 20cm

7. FLAP COMPONENTS
• Can be harvested as cutaneous flap (skin and sub
cutaneous tissue
• Fasciocutaneous flap
• Myo-cutaneous flap (Vastus lateralis muscle)
• Chimeric flap (Rectus femoris muscle,
Tensor fascia lata)

8. FLAP
DESIGN
• Important landmarks include
• Anterior superior iliac spine
• Superior lateral border of the patella.

9. • The flap is centered at the midpoint of a
longitudinal line drawn between these
two landmarks.
• A circle of 3 cm radius defines the area
at which the skin vessels, either
septocutaneous vessels or
musculocutaneous perforators, exit.
• Often found in the inferior lateral
quadrant of the circle.

10. 1. Although a large skin paddle up to 35
cm long and 25cm wide can be
harvested on a single dominant
perforator
• 2.When possible, incorporation of two
perforators within the flap ensures
greater success.
• 3. An eccentric flap with the skin vessel
entering at the proximal portion of the
flap will allow for greater pedicle
length.

11. PRE-OP EVALUATION
• Functional evaluation of knee extension
• Previous scars that may affect flap design.
• Prior skin graft donor sites can beincorporated as part of
the flap.

12. Flap harvesting
⚫Initial skin incision on anerior aspect (exploratory
incision) , 2-3 cm medial to lateral inter-muscular
septum.
⚫Sub-fascial – incision through deep fasciawith lateral
dissection until perforators identified
⚫ Supra-fascial - for thin flap carried laterallyuntil
perforators identified

13. Flap harvesting
⚫Skin incision completed afterperforator identification
⚫Retrograde dissectionof pedicle todescending
branch
⚫May involvedissectionof VL. A cuff of muscle may be
left toprotectperforating branches.

14. Medial flap incision & septum identification

15. Opening of septum

16. Septum dissection distal to proximal

17. Medial retraction of RF &
Identification of pedicle

18. Dissection of perforator

19. Medial retraction of RF &
Identification of DLCFA

20. D O N O R SITE C L O S U R E A N D M A NA G E M E N T
• Closed Primarily, longitudinal linear scar, if width of the flap harvested is less
than 8cm.
• Wider defects will require closure with a split-thickness skin graft.

21. FLAP
USAGE
Pedicled
Lower abdominal
wall
Groin
Suprapubic region
Lateral gluteal area
Knee
Free flap
Perineum
Head and neck
Orofacial
Esophagus
Abdominal wall
Breast reconstruction
Perineal
reconstruction
Upper extremity
Lower extremity

22. ADVANTAGES • Ease of harvest
• Relatively constant anatomy
• Long length and large pedicle.
• Versatility in design with variable
thickness and incorporation of various
tissue components.
• Ability to provide sensory innervation.
• Lack of significant donor site morbidity
• Decreased operative time with two-
team approach.

23. DISADVANTAGES
• Color mismatch in some patients for
facial reconstruction.
• Presence of hair in some male patients.
• Skin graft requirement at donor site if
greater than 8 cm width of harvested
tissue.
• Lack of vessels with reasonable size in
rare cases.
• Excess flap bulk -requiring secondary
flap debulking.
• Fistula and stricture --
pharyngoesophageal reconstruction.
• Breast reconstruction--fat necrosis

24. THANKYOU