Lower Limb Joints Flashcards
What are the 2 important joints of the foot? What are these joints important for?
subtalur joint
transverse joint
**important for: inversion, eversion
What are the bones that make up the subtalur joint?
the talus & calcaneus
What are the bones that make up the transverse joint?
the cuboid/navicular & talus/calcaneus
What makes up the actual ankle joint?
the tibia/fibula & the talus
What is an interesting feature of the ankle joint that allows it to be tightly packed in one position & loosely packed in another? Which positions are these?
The inferior articular surface for the trochlea of the talus is wider anteriorly & narrower posteriorly. The talus is also wider anteriorly & narrower posteriorly. In Dorisflexion, the joint is tightly packed. In plantar flexion, it is loosely packed.
In which position, are you likely to get an inversion/eversion sprain?
when you are in plantar flexion. Your joint is loosely packed & if you jump & land wrong or something–>sprain!
Which ligaments attach the tibia & fibula together?
interosseous membrane
anterior tibiofibular ligament
posterior tibiofibular ligament
In inversion the bottom of your foot points which way?
inward. You gotta remember this, Michelle!
How many axes does the ankle joint have? What are its actions?
1 axis. Uniaxial.
Flexion & extension are its actions.
So, if your ankle is uniaxial, how do you accomplish eversion & inversion?
thru the action @ the subtalar & transverse joint.
What are the ligaments that prevent abduction & adduction @ the ankle jt?
posterior tibiofibular ligament
posterior talofibular ligament
calcaneofibular ligament
Where is the deltoid ligament? What is its fcn?
this is located medially on the ankle jt
its fcn is to stabilize the ankle jt on its medial aspect
Is it common to tear the deltoid ligament? When you do tear it, how does it happen?
Not common. When it does happen–>it is serious.
Happens w/ eversion sprain. Turning the bottoms of your feet outward. Inversion sprains are more common.
What does the inferior fibular retinaculum hold?
the tendons of the fibularis longus & brevis.
What is the sustentaculum tali? What sits beneath it?
it is a ridge of bone that is a part of the calcaneus.
it holds the flexor hallucis longus tendon.
What is the journey of the flexor hallucis longus tendon? Who are his buddies?
tibialis posterior, flexor digitorum longus, an artery & nerve, and flexor hallucis longus start in the posterior compartment & then pass posterior to the medial malleolus & medially onto the plantar aspect of the foot.
Where does “pronation/supination” of the foot happen?
@ the tarsometarsal joint
**we won’t talk about it much.
Which joint is used for amputation?
the transverse tarsal joint
In the most common type of sprain (inversion) what is the most common injury? What is another injury that could happen?
Most common: tearing of the anterior talofibular ligament
Other one: can tear a bit of the 5th metatarsal off b/c of the actions of the fibularis longus & fibularis brevis.
What is the name of the most notable eversion injury? What is the ligament associated with this?
Pott’s fracture-dislocation
deltoid ligament tears
**malleoli might break off.
What are the 2 arches of the foot?
longitudinal arch
transverse arch
What are the 2 things that maintain the arch of the foot?
bones of the foot
ligaments of the foot
Which ligaments of the foot support the arch?
tibialis anterior tibialis posterior fibularis longus flexor hallucis longus flexor digitorum longus
Where is the longitudinal arch higher & lower?
Higher @ medial side
Lower @ lateral side (think footprint)
The tibialis anterior meets up with which tendon?
fibularis longus
What are the 3 important ligaments on the plantar aspect of the foot? These 3 provide some arch support.
Superficial–>Deep
Plantar Aponeuroses
Long & Short Plantar Ligaments
Spring Ligament
What is another name for the spring ligament?
calcaneonavicular ligament
Where does the long plantar ligament connect to?
the calcaneus
it then fans out to the metatarsals.
Where does the short plantar ligament connect to? What is another name for this ligament?
calcaneus–>cuboid
**called the calcaneocuboid ligament
Describe a flat foot & the different types of this.
loss of arch. particularly in the longitudinal direction.
need an arch support.
If flexible: have normal arch when not weight-bearing.
If rigid: have flat arch even when not weight-bearing.
What makes foot arches really cool?
they absorb shock.
What is the structure of the synovial membrane on the knee?
it doubles over & kind of acts like a bag.
Which ligaments are found in the intercondylar fossa? What are they considered? Are they covered in synovial fluid?
ACL & PCL (cruciate ligaments)
Considered intracapsular ligaments
NOT bathed in synovial fluid b/c the synovial membrane takes a different route.
What important thing attaches to Gerdy’s tubercle?
the IT band
What important thing attaches to the tibial tuberosity?
the patellar ligament
Note: The patellar tendon wraps around the superior aspect of the patella & then continues down & wraps around as the patellar ligaments to the tibial tuberosity.
The tibial plateau articulates with what?
with the condyles of the femur. This isn’t a super tight thing & thus the knee is a loose packed joint.
What are 2 close packed joints?
shoulder, hip
What is the fabella?
this is a little bone found in the lateral head of the gastrocnemius; it is a sesamoid bone
T/F The patellar ligament distance adjust with flexion & extension.
FALSE
Its length does NOT change.
the patella moves according to your action & the tension is put on the tendon of the quads.
What is the main purpose of the patella?
it is to increase the power, fulcrum of the joints…not really to protect the knee joint.
What are the 2 cruciate ligaments? Where do they attach?
ACL & PCL
go from femur to the tibia. Attach to the intercondylar eminence.
What are the 3 categories of ligaments around the knee?
Extracapsular ligaments
Intracapsular ligaments
Capsular ligaments
What is the LCL or fibular collateral ligament?
extracapsular ligament
**it is considered extra capsular b/c it doesn’t attach to the lateral meniscus.
What is the MCL or tibial collateral ligament?
capsular ligament
**It looks like a thickening of the capsule. Has portions attaching to the medial meniscus.
If you tear your MCL, what could also happen?
you could also tear off a portion of the medial meniscus.
T/F An LCL tear can NEVER damage the lateral meniscus.
False. Okay, so usu it won’t b/c it is extra capsular & not attached to the lateral meniscus. But sometimes, it can.
What are the collateral ligaments both considered?
supporting ligaments! How sweet of them!
What does genu varus look like? What ligament prevents this from happening?
bow legged
prevented by LCL
What does genu valgus look like? What ligament prevents this from happening?
knock kneed
prevented by MCL
Do men or women have a greater Q angle?
Women b/c they have wider hips.
Men have more varus usu.
In the valgus position, which way does the patella move?
it moves laterally.
Which ligament prevents abduction @ the knee?
MCL
Which ligament prevents adduction @ the knee?
LCL
Which is torn more: the LCL or MCL? Why?
The MCL is torn more b/c most knee injuries happen from the lateral side
Which ligament is theoretically stronger: the LCL Or MCL? Which is thicker?
the LCL is theoretically stronger, but the MCL is thicker.
The ACL limits ______ displacement of the tibia.
anterior
The PCL limits _______ displacement of the tibia.
posterior
Which ligament keeps the femur from sliding forward if you are walking & stop suddenly?
the PCL; it is stronger than the ACL ligament.
Describe how you can strain your ACL.
lateral posterior aspect of the knee is hit. the tibia is pushed forward–>this strains the ACL
Describe the relative positions that the ACL & PCL have on the tibia around the intercondylar eminence.
ACL attaches anteromedially.
PCL attaches posterolaterally.
Describe the relative positions of the ACL & PCL on the femur.
ACL attaches to the femur posterolaterally.
PCL attaches to the femur anteromedially.
Which meniscus attaches to a ligament?
the medial meniscus attaches to the MCL
Describe the medial meniscus.
C-shaped
firmly attached to the MCL
more fixed in place
extends farther/tracks farther
Describe the lateral meniscus.
O-shaped
free to move
T/F The knee can undergo rotation.
True. Up to 30 degrees.
best when flexed
moves more laterally than medially
T/F the lateral meniscus moves with the lateral femoral condyle as it is rotating.
True.
What are popliteal cysts?
fluid-filled herniations of the synovial membrane of the knee joint
goes to show that the synovial sac is large & has quite the ability to distend
ACTUALLY, THE GASTROCNEMIUS IS NOT THE ONLY POSTERIOR MUSCLE TO CROSS THE KNEE JT. There are 2 others. What are they?
Plantaris tendon/muscle
Popliteus muscle
Which nerve innervates the popliteus muscle?
the tibial nerve
What is the function of the popliteus muscle?
It unlocks the knee jt when it is fully extended. When the knee is fully extended, it is slightly medially rotated. With the popliteus, it is slightly externally rotated & unlocked!
Describe the origin & insertion of the popliteus muscle.
Origin: on the medial side of the tibia.
Insertion: on the lateral side of the femur.
put your hand behind your knee & it looks like this.
**will make the femur go lateral.
What is the test for the ACL? For the PCL?
ACL: test is anterior drawer test
PCL: test is the posterior drawer test
What is the acetabular labrum?
this is a cartilaginous piece that attaches to the limbus (margin of the acetabulum)
this is much deeper than the glenoid labrum, adds a lot more contact w/ the head of the femur
What is the lunate surface?
the area where the femur makes contact with the cartilage
What’s cool about the acetabular notch?
it gives you entrance into the acetabular fossa where the obturator artery & other fun things are located.
What is the greatest limiting factor for movement of the hip jt?
the capsular ligaments:
Iliofemoral, ischiofemoral & pubofemoral ligaments
Where do these capsular ligaments for the hip attach?
go from the pelvis (ileum, ischium, pubis) to the femur
When are the capsular ligaments of the hip strongest?
strongest when the hip is in fully extension, wind around each other
weakest @ 90 degrees of flexion (unwound)
Which position of the hip most predisposes it to dislocation?
flexion
Describe the blood supply to the femoral head.
Early in life there was an artery to the femoral head, but it regresses. Then there are perforating branches off the medial (esp) & lateral femoral circumflex that go to the head.
Which of the 3 capsular ligaments of the hip is the strongest?
the iliofemoral ligament
What does the ligament to the head of the femur do?
it holds the head of the femur in place.
A broken hip can often cause loss of blood supply to what?
femoral head & neck
How could a broken hip lead to AVN?
if the break in the femur is proximal to the blood supply–>avascular necrosis of the femoral head.
What is SCFE?
slipped capital femoral epiphysis
**widening & blanching of the epiphyseal plate
often happens to active overweight kids
destroys blood vessels to the head of the femur
considered an emergency if it slips
often treated with internal fixation of a screw.
