lower limb- fascia, vessels, cutaneous nerves

Question 1

describe the attachments of the fascia lata (5 points)

Answer 1

• the fascia lata is the deep fascia of the thigh.
• antero-superiorly attaches to the inguinal ligament, body of pubis and pubic tubercle as well as to the the superficial fascia/subcut tissue of the abdominal wall
• supero-laterallylaterally to the iliac crest
• supero-posteriorly to the sacrum, coccyx, sacrotuberus ligament and ischial tuberosity
• inferiorly to the exposed parts of bones around the knee and deep fascia of the leg

Question 2

what is the iliotibial tract? (2 points)

Answer 2

• thickening of the fascia lata laterally. is the conjoint aponeurosis of the tensor fascia lata and the gluteus maximus muscles. extends from the iliac tubercle to the anterolateral tibial tubercle.

Question 3

what are the three compartments in the thigh and the septa that separate them (2 points)

Answer 3

• the three septae are the lateral IM septum (the strongest) and the posterior and medial septae
• these create anterior, posterior and medial compartments.

Question 4

what is the saphenous opening? (3 points)

Answer 4

• and opening in the fascia lata inferior to the medial part of inguinal ligament.
• medial margin is smooth and lateral/superior/inferior margins form the sharp falciform margin
• the opening is covered by the fibre-fatty cribiform fascia which is pierced by a number of openings for lymphatic vessels and for the great saphenous vein and its tributaries.

Question 5

what are the compartments and septae of the lower leg? (2 points)

Answer 5

• compartments are anterior, posterior and lateral
• the tibia and fibula are joined by the interosseous membrane, anterior and posterior IM septae attach to the fibula (creating the lateral compartment, the posterior compartment is divided into deep and superficial layers by the transverse IM septum.

Question 6

what are the major superficial veins in the lower limb? (1 point)

Answer 6

• the great and small saphenous veins.

Question 7

describe the path and tributaries of the great saphenous vein (7 points)

Answer 7

• formed by union of the dorsal vein of great toe and the dorsal venous arch
• ascends anterior to the medial malleoulys
• passes posterior to the medial condyle of the femur
• anastomoses freely with the small saphenous vein
• traverses the saphenous opening in the fascia lata
• empties into the femoral vein
• significant tributaries include the accessory saphenous vein (posteromedial thigh), lateral and anterior cutaneous veins, superficial circumflex iliac, superficial epigastric, external pudendal

Question 8

describe the path and tributaries of the small saphenous vein (6 points)

Answer 8

• arises on the lateral side of the foot from the union of the dorsal vein of the little toe with the dorsal venous arch
• ascends posterior to the lateral malleoulus
• passes along the lateral border of the calcaneal tendon
• inclines to the midline of the fibula and penetrates the deep fascia
• ascends between the heads of the gastrocnemius muscle
• empties into the popliteal vein in the popliteal fossa

Question 9

what are the deep veins of the leg? (1 point)

Answer 9

• in the lower leg the medial and lateral plantar veins become the posterior tibial and fibular veins. the dorsal venous arch and the perforating veins drain into the anterior tibial vein. the three major deep lower leg veins drain into the popliteal vein which then becomes the femoral vein. the femoral vein passes deep to the inguinal ligament to become the external iliac vein. some perforating veins in the upper leg drain first into the deep vein of the thigh which also drains into the femoral vein

Question 10

describe the lymphatic drainage of the lower limb.

Answer 10

• divided into superficial and deep systems
• superficial system accompanies the saphenous vessels and drains into superficial inguinal lymph nodes
• from the superficial inguinal lymph nodes drainage is mainly to the external iliac lymph nodes but also to the deep inguinal lymph nodes
• some also accompany the small saphenous and drain into popliteal lymph nodes
• deep lymph vessels accompany the deep veins and eventually drain into the external and common iliac lymph nodes and are received by the lumbar lymphatic trunks.

Question 11

what are the clunial nerves

Answer 11

• the superficial gluteal nerves,
• supply all the skin in the gluteal region
• superior, middle and inferior branches exist

Question 12

what do the deep gluteal nerves do

Answer 12

• these are the superior and inferior gluteal nerves, the sciatic nerve, the nerve to quadratus femoris, posterior cutaneous nerve of thigh, nerve to obturator interns and pudendal nerve
• superior gluteal nerve runs laterally b/w gluteus medius and minimus, supplies both these muscles
• ingeferior gluteal nerve leaves pelvis through greater sciatic foramen inferior to piriformis, provides motor innervation to gluteus maximus
• the sciatic nerve is very large, also emerges out the greater sciatic foramen, runs under gluteus maximums, midway between the greater trochanter and ischial tuberosity. supplies posterior thigh muscles + all of leg and foot muscles and skin. becomes two branches- common fibular nerve and tibial nerve
• nerve to quadratus femoris supplies quadratus femoris and inferior gemellus
• posterior cutaneous nerve of thigh supplies skin of inferior buttock, thigh and some perineum
• pudendal nerve exits pelvis through the greater sciatic foramen then enters perineum through lesser sciatic foramen. is principal nerve to perineum
• nerve to obturator internus supplies obturator internus