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