Lower Extremity Joints Flashcards
which bones are involved in the knee joint
femur
tibia
patella
name the two articulation of the knee joint
femorotibial and patellofemoral
what are the two separate joint surfaces of the femorotibial
medial and lateral
what kind of joint is the femorotibial
modified hinge (type of synovial joint)
what kind of joint is the patellofemoral joint
plane type of synovial joint
what is the weight bearing axis of the knee joint
passes through center of femoral head, through middle of knee, to middle of ankle
what is genu varum
bow leg
what is genu valgum
knock knee
what are the motions of the knee joint
flexion/extension
medial and lateral rotation
when does knee rotation not occur
when knee is extended
how many ligaments contribute to knee stability
7
what do tears of MCL often also tear
medial meniscus
the MCL is what kind of collateral ligament
tibial
the LCL is what kind collateral ligament
fibular
what are the functions of the ACL
- Resists anterior translation of Tibia on Femur
- Resists Hyperextension of Knee
- Stabilizes Knee during Rotation
which ligament is stronger and thicker than ACL
PCL
what is the function of the PCL
Resists posterior translation of Tibia on Femur
what is the function of the APL (arcuate popliteal ligament)
stabilizes posterior capsule
what is the function of the OPL (oblique popliteal ligament)
stabilizes posterior capsule
the tibiomeniscal ligaments include what ligaments?
coronary ligaments
what is the function of the tibiomeniscal ligaments
attach menisci to tibia
what ligaments tighten when the knee is locked
collateral and portions of the cruciate ligaments
the combined efforts of ___________ and ____________ provide stability of the knee
ligamentous structures and muscle activity
what kind of joint is the proximal tibiofibular joint
planar type of synovial joint
what are the articular surfaces of the proximal tibiofibular joint
head of fibula and lateral condyle of tibia
what ligaments strengthen the proximal tibiofibular joint
anterior and posterior tibiofibular ligaments
what is the posterior band of the proximal tibiofibular ligament covered by
popliteus tendon
describe the movement that occurs when proximal tibiofibular joint is in use
slight movement occurs during dorsiflexion/plantarflexion of ankle and pronation/supination of subtalar joint
what fibrous joint is essential for ankle joint stability
distal tibiofibular joint
what are the articular surfaces for the distal tibiofibular joint
medial surface of inferior end of fibula and facet on inferior end of tibia
a high ankle sprain stretches/tears ____________
syndesmosis
a “regular” ankle sprain is a stretch/tear of ________
anterior talofibular ligament (most common)
calcaneofibular ligament
posterior talofibular ligament
what kind of joint is the ankle
hinger joint
most of the stability of the ankle is due to __________
bony architecture
what motion does the ankle joint allow
allows dorsiflexion/plantarflexion
what does the deltoid ligament of ankle resist
valgus (medial) angulation
what is the function of the lateral collateral ligaments of the ankle
generally opposes inversion of ankle
which of the 3 lateral collateral group of ligaments is most commonly sprained
anterior talofibular
which joint is more stable in extreme dorsiflexion due to wedging of talus between the medial and lateral malleoli
talocrural joint
what kind of joint is the subtalar (talocalcaneal) joint
plane synovial joint
what are the articular surfaces of the subtalar (talocalcaneal) joint
talus and calcaneus
what movement is allowed by the subtalar (talocalcaneal) joint
- Triplane movement in foot/ankle (non-weight bearing)
- Supination = Inversion + Adduction + Plantarflexion
- Pronation = Eversion + Abduction + Dorsiflexion
Metatarsophalangeal (MTP) joint is what kind of joint
condyloid type of synovial joints
what motion does MTP joint allow
flexion/extension, some abduction/adduction, circumduction
what kind of joint are the interphalangeal joints (IP, PIP, DIP)
hinge type of synovial joints
what motion do the interphalangeal joints allow
flexion/extension
what is the degree of alignment of the knee joint for women vs men
women - 7 degrees
men - 9 degrees
what are the 4 main (out of 7 total) ligaments of the knee
MCL (medial collateral ligament)
LCL (lateral collateral ligament)
ACL (anterior cruciate ligament)
PCL (posterior cruciate ligament)
what portion of knee is attached to medial meniscus
deep portion of MCL
when is the ACL taut
when knee is extended
when is the ACL flexed
when the knee is flexed
