Overview Of Lower Extremity

Front 1

Great Saphenous Vein Course

Back 1

1. union of dorsal and plantar veins and dorsal venous arch of foot

2. medial side of foot

3. anterior to medial malleolus

4. one hands width posterior to medial boarder of patella at knee

5. drains into femoral vein just below inguinal ligament

**distal site used to make skin incision for placement of a cannulla (saphenous cutdown)

Front 2

small saphenous vein

Back 2

1. lateral side of foot

2. exits posterior to medial malleolus

3. continues up posterior side leg

4. empties into popliteal vein in popliteal fossa

Front 3

accessory saphenous vein

Back 3

1. communication between greate and small saphenous

Front 4

varicose veins

Back 4

if walls lose elasticity may become weak and dilated under pressure gravity

incompetent or dilated valves

Front 5

superficial veins clinically

Back 5

may be harvested for coronary bypass surgery

superficial and deep veins in LE anastomose via clinically important perforating veins

Front 6

Lymphatics

Back 6

- both superficial and deep vessels

- most lymphatics follow superficial veins into superficial inguinal lymph nodes

- deep lymphatics:

accompany deep veins-> external iliac-> common iliac-> lumbar lyphatic trunks-> cisterna chyli-> thoracic duct

Front 7

Anterior and posterior divisions of the lumbar and sacral plexus

Back 7

- rotation of lower limb complicates neuromuscular relationships

- anterior division nerves supply those regions that represent the original ventral or flexor surface

- posterior divisions supply those regions that represent original dorsal or extensor surface

Front 8

Lumbar plexus

Back 8

- posterior abdominal wall

- L1, L2, L3, L4

- two anterior divisions: obturator and accessory obturator

- two posterior divisions: Femoral and lateral femoral cutaneous nerves

Front 9

sacral plexus

Back 9

- lateral wall of pelvis

- major contributions from L4, L5 (lumbosacral trunk)

- ventral rami S1, S2, S3, and part of S4

Front 10

posterior cutaneous nerve of the thigh

Back 10

- contains nerve fibers from both anterior and posterior divisions

- lies at boundary between original embryonic dorsal and ventral surfaces

Front 11

adductors and medial rotatiors of the thigh

Back 11

lie on the anteromedial surface and are innervated by an anterior division nerve OBTURATOR

- obturator also supplies secondary flexors of thigh

Front 12

principle flexors of the thigh

Back 12

- iliopsoas, sartorius, and rectus femoris

- lie on anterior surface (embryonic posterior surface)

- innervated by a posterior division nerve (FEMORAL)

Front 13

Extensors, abductors, and lateral rotators of thigh

Back 13

- lie on posterolateral surface

- innervated by posterior division nerves

- SUPERIOR AND INFERIOR GLUTEAL NERVES

Front 14

Extensors of the leg, foot, and toes

Back 14

- lie on the anterior surface

- embryonic posterior surface

- innervated by posterior division nerves

- FEMORAL, COMMON FIBULAR

Front 15

flexors of the leg, foot, and toes

Back 15

- lie on the posterior surface

- embryonic anterior surface

- innervated by anterior division nerve

- TIBIAL NERVE

Front 16

Myotomes: Hip Flexion

Back 16

L1, L2

Front 17

Knee extension

Back 17

L3, L4

Front 18

ankle dorsiflexion

Back 18

L4, L5

Front 19

ankle inversion

Back 19

L5, S1

Front 20

Ankle plantarflexion

Back 20

S1, S2

Front 21

Cutaneous innervation by lower extremity

Back 21

- L1-L5 segments represented as series of bands passing lateral to medial

**bands reflect the medial rotation of the leg and foot during development

-S1-S2 segements are represented as vertical strips that course inferiorly down posterior surface lower limb to foot

Front 22

Dermatomes

L1

Back 22

over inguinal ligament

Front 23

L3

Back 23

lower medial side of thigh to knee

**L3 to the knee

Front 24

L4

Back 24

medial side of ankle to great toe

**L4 to the floor

Front 25

L5

Back 25

dorsal surface over digit II

Front 26

S1

Back 26

little toe and lateral side of foot

Front 27

superficial fascia of thigh

Back 27

- continuous with abdomen and gluteal region

- contains superficial veins, lymphatics, cutaneous nerves, fat

- at knee superficial fascia of thigh blends with deep fascia

Front 28

deep fascia of entire lower limb

Back 28

- extensive and strong

- invests in limb and divides into multiple compartemnts

- limits expansion of contracting muscles

- muscle contraction can effectively compress veins and pump blood out of lower extermity towards heart

Front 29

deep fascia of the thigh

Back 29

- fascia lata

- thickened laterally by aponeurosis from gluteus maximus and tensor fascia lata muscles (IT band)

- thigh muscles separated into compartments by fascia lata and three intermuscular septa:
1. anterior
2. medial
3. posterior