1. Lower Limb Flaps

2. Arteries in the lower leg Common Femoral Artery Dorsalis Pedis Artery and Arcuate Medial circumflex femoral arteryArtery Lateral circumflex femoral artery Deep plantar branch of DP(+ ascending and descending Dorsal metatarsal and digitalbranches0 arteries Profunda Femoris Medial and lateral tarsal arteries Perforating brs of PF Peroneal Artery Descending genicular artery Perforating branch of peroneal Popliteal Arteryartery Ascending branch Lateral malleolar artery Genicular arteries (4) Posterior Tibial Artery Anterior Tibial Artery Medial plantar artery Anterior tibial recurrent artery Lateral plantar artery Medial malleolar arteries Plantar arch, plantar metatarsaland digital arteries 3. Femoral artery 4. Anteromedial thigh flap Femoral artery lies in subsartorial canal for its lower 2/3, and in thisportion gives off muscular and fasciocutaneous branches Perforators pass around both borders of sartorius to form a plexus at the levelof the deep fascia with an axis along the border of sartorius Range in size from 0.5-1mm 80% cases the largest perforator passes around the superomedial border ofsartorius in the apex of the femoral triangle Additionally also supplies muscle, so its diameter is 0.5-1.2mm Accompanied by a vein Supplies an area of 7x12cm on anteromedial thigh, with upper part of ellipse overlying the apex of the femoral triangle Area is supplied by the medial anterior cutaneous nerve of the thigh Crosses medially in front of artery at the apex of the femoral triangle Can be raised as an innervated flap Type B fasciocutaneous flap Raised by identifying perforator first, the adjusting the flap position to becentred over the artery 5. Saphenous flap Saphenous artery is one of three terminal branches of descending genicular branch of femoralartery Given off from medial side of femoral artery immediately before if enters the adductor hiatus Runs under sartorius and sends cutaneous branches anterior and posterior to muscle Runs under insertion of tendon to emerge posteriorly and continue in lower leg, usually only for about 12cm 1.5-2mm, paired vcs + GSV Safe dimensions are 6x20cm, allowing primary closure of defect Raised proximal to distal to visualise vessels and their relationship to tendon first Can raise distally based flap, useful in stump wound breakdown 6. Lateral circumflex femoral artery 7. Tensor Fascia LataeOrigin ASIS + iliac crestInsertion Lateral condyle of tibia via fascia lataInnervation Superior gluteal nerve (L4,5)Action Abducts, medially rotates and flexes thigh. Hip stabiliser and assists in keeping knee extendedType I muscle Branch off ascending branch of lateral circumflex femoral artery Single artery 2-3mm diameter, paired venae comitantes Enters muscle on deep surface 9cm below ASIS 8. Rectus femoris Type II bipennate muscle supplied primarily by LCFA Origin: AIIS and deep/reflected part from superior acetabular rim Insertion: Tibial tuberosity via superior part of patella, separated from femur bysuprapatellar bursa. Deepest layer of quadriceps tendon Innervation: Br of Femoral nerve (L3,4), deep group, usually double Upper branch gives a proprioceptive branch to hip (Hiltons law) Action: Extend knee, stabilise hip joint and assists iliopsoas flex hip Reliable vascular pedicle and considerable length (7x40cm) Pedicle generally arises 5cm below top of symphysis pubis and runs downwards for 5-8cm before piercing the muscle on posteromedial border at junction of proximal and middle thirds Divides into superior and inferior branches Rotation point is 7cm below inguinal ligament Muscle is necessary for fully functional knee extension, so is not expendable except in spinalpatients (when gracilis or TFL can be used) Skin paddle is based over lower 2/3 of muscle Skin paddle sensation is supplied by intermediate anterior cutaneous nerve of thigh 9. Vastus lateralis Type II muscle with dominant proximal pedicle from LCFA augmented by multipleperforators from the posterior compartment Origin: Greater trochanter, lateral lip of linea aspera of femur Insertion: Tibial tuberosity via patella. Middle layer of quadriceps tendon Innervation: Br of femoral nerve (L2,3,4), deep group Action: Extends knee Descending br LCFA runs down behind anterior edge of VL with nerve supply andterminates in muscle in 90%, skin in 10% As branches enter the muscle, multiple neurovascular hila are formed. One intoproximal third, three in proximal and middle third 60% cases, branches pierce deep fascia over anterior part of muscle and supply skin 40% cases septocutaneous perforators given off in intermuscular septum to reach deep fascia (see ALT flap) Main use is in repair of trochanteric pressure sores and salvage of hip wound Can be raised as a free flap Raised as from an incision slightly lateral to a line from ASIS to superolateralaspect of patella 10. Anterolateral thigh flap Type B fasciocutaneous flap Supplied by descending branch of lateral circumflex femoral artery, usuallyassociated with 2 vcs Length 8 16cm, diameter 2-3mm Pedicle transverses obliquely in groove between rectus femoris and vastuslateralis along with nerve to vastus lateralis Cutaneous perforators usually found in inferolateral quadrant of 3cm circlewith centre at midpoint ASIS to superolateral corner of patella Can be septocutaneous or musculocutaneous perforators Can be raised as super thin, fasciocutaneous or musculocutaneous flap Maximum dimensions 12x8cm, with most distal part of flap at least 4cmabove proximal end of patella Can incorporate anterior branch of lateral cutaneous nerve of thigh to createsensory flap 11. Profunda femoris artery 12. Gracilis Origin inferior pubic ramus, just below fascia lata Insertion subcutaneous surface of tibia, just behind sartorius Innervation obturator nerve Single nerve with multiple fascicles to different portions of muscle (so usefulin facial reanimation) Action adduct thigh, flexes leg, assists medial rotation Type II muscle Adductor branch of profunda femoris or descending branch of MCFA Main pedicle 1-2mm diameter, paired vcs One or to minor pedicles from superficial femoral artery enter muscle distally Pedicle courses from medial to lateral, and enters the deep surface about10cm inferior to pubic tubercle (junction of upper 1/3 and lower 2/3) pivotpoint Usually used as muscle only flap, but can be used as musculocutaneousflap with skin island over superior half of muscle 13. Hamstring flaps Hamstring musculocutaneous flapswere developed for treatment ofischial pressure sores, but can betransposed to anterior thigh VY musculocutaneous unitadvancements have the advantage ofbeing able to be re-elevated andadvanced should pressure sores recur Can be raised on all 4 hamstringcomponents or only biceps orsemitendinosis Can be constructed to maintaininnervation via posterior cutaneousnerve of thigh Large skin islands up to 12x35cmextending past the muscle borders canbe raised 14. Biceps femoris Semitendinosis Origin: Long head from ischial Origin: Ischial tuberosity tuberosity, short head from linea Insertion: Medial surface of aspera of lateral supracondylar linesuperior part of tibia, just below of femurgracilis Insertion: Lateral side of head of Innervation: Tibial part of sciatic fibula. Tendon is split by fibularnerve (L5-S2) collateral ligament of knee Action: Extend thigh, flex leg and Innervation: Long head is tibialrotate medially, extend trunk division of sciatic nerve (L5-S2),when thigh and leg are flexed short head is common peroneal Arterial supply: Type II. Primary branch of sciatic nerve (L5-S2) dominant pedicle from first Action: Flex leg and rotate profunda perforator and smaller laterally, extends thighpedicle superior to this from Arterial supply: Type II. Major MCFA. Also small branches from branches from the first profundainferior gluteal to origin, and perforator at upper third junction. inferior medial genicular to Branches from second perforator insertion to lower part of long head and to short head. No anastomoses between short and long head. Further minor supply from inferior gluteal artery, MCFA, sup lat genicular artery 15. Lateral thigh flaps Lateral thigh flaps are based on the perforators from profunda femoris, each of whichterminates by dividing into two branches at the point of the insertion of the lateralintermuscular septum into the femur (deep to origin of short head of biceps femoris) One of these branches pierces lateral intermuscular septum to supply vastus lateralis, theother runs on posterior aspect of intermuscular septum towards the iliotibial tract Consistent large perforator from 1st profunda perforator within 3cm of lower border ofgluteus maximus (may be through the muscle), often the largest of the perforators Can raise skin flaps of up to 8x25cm, usually pedicled (superior lateral thigh flap) due to the relationship to gluteus insertion Also branch from 3rd profunda perforator (ED 1-1.5mm) at midpoint between greatertrochanter and lateral femoral condyle (middle thigh flap) Usually raised as a free flap due to long pedicle length Raised without deep fascia, so small area but thin and can be innervated As most perforators run anteriorly, best to plan this flap with only 1/3 behind lateral intermuscular septum Venous drainage is by paired vcs of the cutaneous perforators that tend to join as theyapproach the femur Nerve supply of the area is the lateral femoral cutaneous nerve Emerges from beneath lateral end of inguinal ligament and divides into 2 branches that run down the iliotibial tract 16. Popliteal artery 17. GastrocnemiusOrigin Medial head Popliteal surface of femur, superiorto medial condyle Lateral head Lateral aspect of lateral condyle offemurInsertion Posterior surface of calcaneus via tendocalcaneus (Achilles tendon)Innervation Tibial nerve (S1,2)Action Plantarflexes ankle, raises heel during walking, flexes knee joint 18. Mathes + Nahai Type I for each head Each head supplied by a sural artery, which arises frompopliteal artery at or slightly above the joint line and is 2-5cmlong Occasionally arises from common trunk, or lateral sural arises withinferior lateral or middle genicular artery Artery to medial head run directly to muscle Artery to lateral head passes anterior to popliteal vein and tibialnerve, may give off branches to plantaris and soleus as well as a smallvessel accompanying surely nerve 3mm diameter with paired vcs, one of which can be up to4mm diameter Enters each head at level of tibial condyles (pivot point), withnerves posterior to artery in 90% cases Within the muscles each sural artery divides into twobranches which run longitudinally between muscle fibrebundles and often subdivide furtherMedial head can reach to lower third femur, whereas lateral head has a smaller arc of rotation 19. SoleusOrigin Inferior end of lateral supracondylar line of femur and oblique popliteal ligamentInsertion Posterior surface of calcaneus via tendocalcaneus (Achilles tendon)Innervation Tibial nerve (S1,2)Action Plantarflexes ankle and steadies leg on foot 20. Mathes + Nahai Type II muscle Dominant proximal supply from popliteal arterybranches and a secondary distal supply frombranches of posterior tibial artery Reverse flap has been described to cover heeldefects, but its reliability is questionableUsed to cover middle third tibial defectsBipennate muscle, so can be split into larger medial flap and a smaller lateral hemisoleus flap 21. Popliteo-posterior thigh flap Inconstant vessel from proximal part ofpopliteal artery, so Doppler assessment isimportant Generally reaches deep fascia 8-10cmabove plane of knee with paired vcs andascends in midline May anastomose with br of inferior glutealartery that accompanies the posteriorcutaneous nerve of the thigh Can raise flap as high as gluteal crease, anddefect can be primarily closed if width