Lower extremity Flashcards
What’s function is to bear weight, provide locomotion, and requires strong bones and mobile joints?
lower extremity
Where is the center of gravity in the lower extremity?
anterior to edge of SII vertebra in pelvis
Where is the leg?
between knee and ankle joint
Where is the foot?
Distal to the ankle joint
What muscles flex the thigh?
iliopsoas (MOST POWERFUL), with sartorius, rectus femoris, pectineus
What muscles extend the hip/thigh?
gluteus maximus and hamstring muscles (semitendinosus, semimembranosus, biceps femoris)
What muscles abduct the thigh?
gluteus medius and minimius (most powerful) with the piriformis and tensor fasciae latae
Also important in stabilizing contralateral hip when walking
What muscles adduct the thigh?
adductor longus, adductor brevis, adductor magnus, gracilis (POWERFUL)
assited by pectineus
What muscles medially rotate the hip?
gluteus medius and minimus and adductors (longus, brevis, magnus)
What laterally rotates the hip?
gluteus maximus (MP), w/ piriformis, obturator internus and externus, gemelli, and quadratus femoris
What is flexion of the leg?
flexion at the knee
What muscles flex the leg?
sartorius, gracilis, hamstrings, gastrocnemius, plantaris
What muscles extend the leg (extend knee)?
quadriceps
When is the ankle most stable?
dorsiflexion
Where does inversion/eversion of the foot mainly take place?
transverse tarsal joint – talonavicular and calcaneocuboid
What muscles invert the foot?
tibialis anterior w/ tibialis posterior
What muscles evert the foot?
fibularis longus, brevis, tertius
Valgus is ___________ and varus is _________
knock-kneed (cLose) and bowleg
What is the massive bone of the thigh and homologue to the humerus?
femur
What is regarded to as a sesamoid bone and increases leverage of quads by making them act at a greater angle?
patella
What is the main weight bearer of the leg?
tibia – easily bruised
T/F: the fibula bears weight
false – NO weight
What’s between the tibia and fibula?
interosseus membrane
“tibiofibular union”
What has:
- resilient arches for shock absorption
- adjustments for uneven ground
- can transfer weight acting as levers?
feet
How many units does one foot have?
3
What makes up the posterior foot unit?
talus and calcaneus
What makes up the middle foot unit?
cuboid, navicular, and 3 cuniforms
What makes up the distal foot unit?
metatarsals (5) and phalanges (14 - 5, 4, 5)
Where can fractures occur when sole of foot is heavily compressed; such as falls landing on the heel?
Talus – can disrupt blood supply and cause necrosis
Where is the most common site of fracture in the talus?
talar neck from direct trauma, or landing from a height
What’s the heel bone?
calcaneus
What does the calcaneus articulate with?
cuboid and talus bones
What is the most common TARSAL fracture?
calcaneal fractures, mostly intra–articular when the talus is driven down into the calcaneus
What is the order of bones in the feet, proximal to distal?
tarsals -> metatarsals -> phalanges
What dislocation is common in athletes and dancers?
1st metatarsal from hyperdorsiflexion
What can occur because of stress on the fibularis brevis tendon?
5th metatarsal avulsion fracture
What can gout cause?
growth in 1st metatarsal of uric acid, caused by undersecretion of urate by kidneys
What is bursae?
small sac w/ synovial lining that contains fluid – reducing friction
What are examples of bursae?
gluteus maximus & greater trochanter
gluteus maximus & ischial tuberosity
gluteus maximus & vastus lateralis
What runs through the femoral triangle?
VAN! and femoral lymphnodes
Femoral artery and nerve
Great saphenous vein
What makes up the lateral compartment of the femoral triangle?
iliopsoas muscle and femoral nerve
What makes up the medial compartment of the femoral triangle?
veins, arteries, lymph nodes
What allows the femoral vein to expand when venous return from LL increases, and contains the Cloquet node?
femoral canal
What is the chief artery of the lower limb and a continuation of the external iliac?
femoral artery
How does the femoral artery become the popliteal artery?
exits adductor canal thru adductor hiatus to become popliteal artery
What is the chief artery of the THIGH with many branches?
profunda femoris
What are the branches of the profunda femoris?
perforating arteries which wrap around femur, supply adductor magnus, hamstring, vastus lateralis
circumflex femoral arteries - medial (head and femur neck), lateral (muscles laterally)
What is the largest branch of the lumbar plexus?
femoral nerve –> saphenous nerve through the adductor canal
What does the obturator artery supply?
From internal iliac!
obturator externus, pectineus, adductors of thigh, gracilis
posterior branch supplies head of femur
What are the contents of the adductor canal?
femoral artery, vein, saphenous nerve
femoral artery easily approached here during surgery
Where is the saphenous opening?
just inferior to the inguinal ligament where great saphenous vein exits (femoral hernia can occur here!)
What are the superficial veins of the leg?
great saphenous vein –> femoral
small saphenous –> popliteal
Where does the superficial inguinal nodes drain into and recieve lymph from?
external iliac
from abdominal wall below umbilicus, vagina, anus, ex. genitalia
Where does the deep inguinal nodes drain into and recieve lymph from?
external iliac
from popliteal, glans penis and clitoris
What is the elastic stocking that forms compartments w/ 3 fascial intermuscular septa that attach to the linea aspera of the posterior femur?
fascia lata
What is the septum in the fascia lata and what it is continuous w/?
lateral intermuscular septum that is continuous with the IT band
What makes up the anterior compartment of the fascia lata?
- extensors of knee - quads
- flexors of hip - sartorius, pectineus, iliopsoas
nerve: femoral
What makes up the medial compartment of the fascia lata?
- adductors of hip - adductor longus, brevis, magnus
- gracilis
nerve: obturator
What makes up the posterior compartment of the fascia lata?
- flexors of knee, extensors of hip: hamstrings
nerve: sciatic
What is the aponeurosis of the tensor fasciae latae and gluteus maximus and extends from iliac tubercle to anterolateral tibial tubercle?
IT band
What helps knee extension?
IT band
What is the syndrome that presents as lateral knee pain caused by inflammation of distal IT band and is caused by excessive friction from repition?
IT band syndrome
Why are fascia lata grafts useful?
high conc. of connective tissue and can be surgically harvested w/ most fibre intact
When does compartment syndrome develop?
significant trauma, involving long bone fractures, minor trauma, anything that decreases compartment space, increasing pressure
Where does compartment syndrome normally occur?
leg, forearm, or foot, thigh, gluteal region
In who is compartment syndrome most common?
<35 yrs of age, men>women, after fractures of tibial diaphysis and distal radius
What nerve passes above the piriformis muscle?
superior gluteal nerve (between medius and minimus and terminates in tensor fascia latae) supplies these!
deep!
What nerve passes below the piriformis muscle?
inferior gluteal nerve and supplies gluteus maximus
deep!
What nerve is inferior to the piriformis?
sciatic nerve! – supplies posterior thigh muscles, leg, and foot
divides into tibial and common peroneal nerves
What is inferior to the piriformis and posterior to the sacrospinous ligament and enters the lesser sciatic foramen into the perineum?
pudendal nerve
What artery is:
* an internal iliac branch
* thru greater sciatic foramen
* superior to piriformis
* nutrient artery to ilium
* supplies maximus, medius, minimus ?
superior gluteal artery
What artery is
* an internal iliac artery branch
* thru greater sciatic foramen
* inferior to piriformis
* supplies maximus and sciatic nerve ?
inferior gluteal artery
What artery is
* internal iliac artery branch
* lateral to the pudendal nerve
* exits thru lesser sciatic foramen
* supplies perineal structures ?
internal pudendal artery
What is the trendelenburg sign?
weakness of gluteus medius and minimus (thigh abductors) – pelvis drops on contralateral side
What is the diamond shaped space behind the knee and an exception to the VAN arrangement?
popliteal space (nerve is most superficial)
What descends through the popliteal fossa to the posterior compartment of the leg and passes behind medial mallelous to reach sole of foot where it divides into medial and lateral plantar nerves?
tibial nerve
What nerve winds around the neck of the fibula, can be easily palpated and easily injured?
common peroneal nerve (superficial and deep), injured by compression or laceration, causing foot drop!
What is the terminal branch of the popliteal artery?
posterior tibial artery –> peroneal artery, anastomoses with arcuate artery of dorsum of foot, terminates into medial and lateral plantar arteries
Where is the dorsalis pedis artery?
space between first two metatarsals, and then divides into deep and arcuate arteries
What attaches to the anterior and medial borders of the tibia and divides the LEG into 3 compartments?
crural fascia/deep fascia of leg
- anterior (dorsiflexor)
- lateral (fibular)
- posterior (plantarflexor)
What foot muscles abduct the toes (dorsal)?
extensor hallucis brevis and extensor digitorum brevis
What foot muscles adduct the toes (plantar) in the 1st layer?
abductor hallucis
flexor digitorum brevis
abductor digiti minimi
What foot muscles adduct the toes (plantar) in the second layer?
quadratus plantae and lumbircal muscles
What foot muscles adduct the toes (plantar) in the third layer?
flexor hallucis brevis, adductor hallucis, flexor digiti minimi brevis
What foot muscles adduct the toes (plantar) in the 4th layer?
dorsal interossei and plantar interossei
What nerve are the nerves of the sole of the foot branches of?
tibial nerve –> medial and lateral nerves
What does the lateral femoral cutaneous nerve innervate (L2-L3)?
skin anterior and lateral thigh
What does the clunial nerve supply? L1-S3
gluteal region
What does the posterior femoral cutaneous nerve supply? S1-S3
lower edge of skin of butt, thigh, to calf
What does the saphenous nerve supply? L3-4
medial leg and foot (vulnerable to injury in varicose vein repair)
What does the lateral sural cutaenous nerve supply? L2-S2
skin on posteriorlateral leg by knee
What does the medial sural and sural nerve supply? S1-S2
back of leg, lateral ankle, heel and foot
What does the superficial peroneal nerve supply? L4-S1
lateral lower leg and dorsum of foot
What does the deep peroneal nerve supply? L4-L5
anterior muscles of leg and foot, skin of first and second toes
