which of the following describe the function of the menisci in the knee?
1. provides blood supply to the peripheral 1/3 of the knee joint
2. provides stability to the knee joint
3. distributes force across a larger area to decrease pressure
4. slows the rate at which articular cartilage at the knee breaks down
-1 + 2
-2, 3, + 4
-1, 3, + 4
-all of the above
2, 3, + 4
-EXPLANATION:
-1 is not correct because the menisci do not supply blood, they RECEIVE blood flow; the peripheal 1/3 of the meniscus is vascularized
-2 is correct because the menisci support the round femoral condyles on the flat tibial plateaus, increasing joint congruity + thus stability
-3 is correct because the menisci increase the surface area of contact between the femur + tibia; pressure = force/area, so the more surface area the less pressure
-4 is correct for the same reason as 3, just more application based; because there is less pressure at the joint, the breakdown of cartilage slows
in which of the following MOI (mechanisms of injury) would you most likely expect the patients PCL to be injured?
-valgus force to the knee
-varus force to the knee
-dashboard injury in MVC in which the tibia is pushed backwards on the femur
-hyperextension injury in which the tibia is pushed forwards on the femur
dashboard injury in MVC in which the tibia is pushed backwards on the femur
-EXPLANATION: C is correct because the PCL is the primary restraint that prevents posterior translation of the tibia on the femur
-A is incorrect because a valgus force to the knee would likely cause injury to the MCL
-B is incorrect because a varus force to the knee would likely cause injury to the LCL
-D is incorrect because a hyperextension MOI would likely cause injury to the ACL
you are doing an open chain knee extension at the gym. which of the following is happening arthrokinematically at the knee as you move from flexion into extension?
-the femoral condyles roll anteriorly + glide posteriorly on the tibial plateaus
-the femoral condyles roll posteriorly + glide anteriorly on the tibial plateaus
-the tibial plateaus glide anteriorly on the femoral condyles
-the tibial plateaus glide posteiorly on the femoral condyles
the tibial plateaus glide anteriorly on the femoral condyles
-EXPLANATION: in the open chain extension of the knee, the tibia is moving on the femur, so A + B are incorrect
-A -> closed chain extension
-B -> closed chain flexion
-D -> open chain flexion
which of the following correctly match patella alta/baja to the associated patellar tendon length? 2 answers are correct
-patella alta/patellar tendon too short
-patella alta/patellar tendon too long
-patella baja/patellar tendon too short
-patella baja/patellar tendon too long
B + C (patella alta/patellar tendon too long + patellar baja/patellar tendon too short)
-EXPLANATION:
-patella baja is when the patella sits too low in the knee joint, characterized by a shortened patellar tendon
-patella alta is when the patella sits too high in the knee joint, characterized by a lengthened patellar tendon
if the meniscus has sustained an injury, what part of the meniscus has a better chance of healing due to its vascularity?
-medial 1/3 (white zone)
-anterior horn
-lateral 1/3 (red zone)
-lateral horn
lateral 1/3 (red zone)
-EXPLANATION: the lateral 1/3 of the meniscus is referred to as the “red zone”; this is because it is the only part of the meniscus that has some sort of vascularization
-so if an injury were to occur in this area, the chance of it recovering are much higher than any other part of the meniscus
-slide 9 of knee TF lecture
during the last 20-30 degrees of knee extension, the tibia will externally rotate. what is the mechanism behind this?
-screw home mechanism
-patellar tension mechanism
-Q angle mechanism
-symmetry of the femoral condyles
screw home mechanism
-EXPLANATION: the screw home mechanism is due to the asymmetry of the femoral condyles + how the tibia will move on it as it goes into extension or flexion
-since the medial condyle of the femur is larger than the lateral condyle, as the tibia continues to slide forward it will stop on the lateral condyle before the medial
-since there is much more room to go on the medial side, the tibia will then begin to rotate to fix it into place on the femur to give the knee stability when in extension
-slide 4 of TF movement lecture
if a patient presents to the EAC clinic with a genu varum stance, where would most of their weight bearing force be located?
-towards the front of the joint space
-towards the medial part of the joint space
-towards the lateral part of the joint space
-the weight bearing force is equal
towards the medial part of the joint space
-EXPLANATION: genu varum is when the knees are in a varus position, meaning the legs are starting to go outwards
-as a result, the force for weight bearing will be in the medial part of the joint space as the line of force is now disturbed + must now run from the center of the hip to the medial side of the knee as opposed to a knee having the force run from the center of the hip to the medial aspect of the knee
-slide 5 of knee TF lecture
a patient presents to you in the clinic following an injury while playing soccer. they tell you that someone had tried going for the ball + in doing so had kicked your knee from the outside instead thus causing your leg to cave in. what is the most likely structure that is affected?
-LCL
-arcuate ligament
-quadriceps
-MCL
MCL
-EXPLANATION: remember that the MCL is the primary resistor for any sort of medial force of the knee; so if an injury occured where it caused the knee to buckle, the first most likely to go would be the mcl
-after it would be the secondary restraint which is the ACL + then if all else fails the dynamic stabilizer would be all that left stabilizing medial force of the knee would be the pes anserinum
-slide 17 of knee TF lecture
which joint primarily allows dorsiflexion + plantarflexion of the foot?
-subtalar joint
-talocrural joint
-midtarsal joint
-tarsometatarsal joint
talocrural joint
-EXPLANATION: the talocrural joint is a hinge joint, which means it allows for rotation around a single axis
-in addition to dorsiflexion + plantarflexion, the talocrural joint may also allow for small amounts of inversion (turning the sole of the foot inward) + eversion (turning the sole of the foot outward)
-however, these movements are primarily controlled by other joints in the foot, such as the subtalar joint
which muscles are the primary plantarflexors of the ankle? (select all that apply)
-gastrocnemius
-soleus
-tibialis posterior
-fibularis (peroneus) longus
gastrocnemius + soleus
-EXPLANATION: they are responsible for the main power in moving the ankle to point the toes downward, as in standing on your tiptoes + are essential for propulsion during activities like running + walking
-other muscles that also assist in plantarflexion include the tibialis posterior, flexor digitorum longus, flexor hallucis longus, + peroneus longus + brevis
T/F- the medial malleolus is posterior compared to the lateral malleolus
false
-EXPLANATION: the lateral malleolus is positioned more posteriorly than the medial malleolus
-this specific anatomical arrangement helps form the ankle “mortise” (socket), which provides stability to the ankle joint during movement
which movement combination occurs at the subtalar joint during pronation in the open-chain motion?
-calcaneal dorsiflexion, abduction, inversion
-calcaneal plantarflexion, adduction, inversion
-calcaneal dorsiflexion, adduction, inversion
-calcaneal plantarflexion, abduction, eversion
calcaneal dorsiflexion, abduction, eversion
-EXPLANATION: in an open-chain movement, the distal segment (the calcaneus) is free to move on the relatively fixed proximal segment (the talus)
-as it everts, the lateral side of the foot lifts
-abduction occurs as the foot moves away from the midline (toes point outward)
-dorsiflexion occurs as the calcaneus tilts upward on the talus
put yourself in the shoes of the LA chargers AT this past sunday. star offensive tackle Joe Alt just went down so you run out to tend to him. Alt immediately says “my mortise feels completely unstable!”. what ligament do you suspect is damaged? (hint: Joe Alt suffered a high ankle sprain)
-deltoid ligament
-anterior inferior tibiofibular ligament (AITFL)
-anterior talofibular ligament (ATFL)
-anterior superior tibiofibular ligament (ASTFL)
anterior inferior tibiofibular ligament (AITFL)
-EXPLANATION: the AITFL stabilizes the inferior articular between the tibia + fibula, which forms the mortise where the talus sits
-also the AITFL is the most commonly injured ligament in a high ankle sprain
you just ran from HPNP to CLC to make it in time for functional because you had cadaver lab D today. you noticed when you were running, every time your toes planted (fully extended), you felt a tight stretch on the bottom of your foot. because you regularly stretch your toe flexors, you suspect it is your ____
-long plantar ligament
-spring ligament
-plantar aponeurosis
-achilles tendon
plantar aponeurosis
-EXPLANATION: the plantar aponeurosis attaches from the heel to the proximal phalanx + is stretched on toe extension
a patient presents with limited knee extension ROM. they describe it as “my kneecap feels stuck when I straighten my knee”. what type of treatment intervention may help this patient?
-force their knee into extension because they’re being soft
-inferior patellar glide
-superior patellar glide
-inferior pole palpation
superior patellar glide
-EXPLANATION: the patella glides superiorly when the knee is extended, so doing a superior patellar glide on this patient would help facilitate knee extension
it’s bottom of the 9th inning in the Grad Cup softball finals. Bryce Cota reluctantly takes the plate to drive in Jeter from 3rd for the game winning run to beat law. the law school pitcher throws the worst ball you have ever seen + Bryce stands up to regain his composure trying not to laugh. what is happening at Bryce’s knees in the terminal part of his transition from a batting stance to standing up?
-internal rotation of the tibia
-external rotation of the tibia
-external rotation of the femur
-internal rotation of the femur
internal rotation of the femur
-EXPLANATION: during closed chain knee extension, the last 20-30 degrees of knee extension invovle the femur internally rotating on the tibia due to the medial condyles of each being larger
-this is the opposite of open chain knee extension in which the tibia externally rotates
a 22 year old soccer player presents to EAC with complaints of his knee “giving way” after sudden stops or changes in direction. upon examination, there is increased anterior translation of the tibia relative to the femur. which structure is most likely injured, leading to anterior instability of the knee?
-PCL
-MCL
-ACL
-LCL
ACL
-EXPLANATION: the primary restraint for anterior joint stability of the knee is the anterior cruciate ligament, so if this patient was experiencing anterior instability the ACL would most likely be injured
-slide 15 of knee TF lecture
you walk into functional anatomy early + witness Demi Lovato attempting to teach Dr. Bishop how to perfect his disney knees. what does his stance functionally mimic?
-genu varum
-genu valgum
-genu recurvatum
-genu flexum
genu valgum
-EXPLANATION: the “disney knees” pose creates a valgus alignment, aka knees angle inward
-A is incorrect because genu varum is knees angled outward
-C is incorrect because genu recurvatum is hyperextension of the knee
-D is incorrect because genu flexum is persistent knee flexion
you are attempting to palpate your partner’s semitendinosus in lab. what characteristics would you look for when palpating?
-superficial, have pt flex knee + IR tibia, medial thin tendon
-deep, have pt flex knee + IR tibia, broad muscle belly
-posterolateral, have pt flex knee + ER tibia, lateral thin tendon
superficial, have pt flex knee + IR tibia, medial thin tendon
-EXPLANATION: when palpating semitendinosus, locate posteromedial thigh + have pt flex their knee + IR their tibia (turn foot inward)
-a thin, cord-like tendon will become visible on the medial side of the popliteal fossa
-B is incorrect because it is for semimembranosus (deeper, larger muscle belly)
-C is incorrect because it is for biceps femoris (more lateral + ER vs IR)
which of the following ligaments of the knee is intra-articular (within the knee joint)?
-MCL
-LCL
-oblique popliteal ligament
-PCL
PCL
-EXPLANATION: the ACL + PCL are the only ligaments of the knee that lie within the joint capsule (intra-articular)
-slide 11 of knee TF lecture
T/F- the lateral femoral condyle is larger + extends further distally than the medial femoral condyle
false
-EXPLANATION: the medial femoral condyle is larger + extends further to maintain contact with the tibial plateau throughout knee movement to contribute to the screw-home mechanism
which if the following hamstring muscles attaches to the meniscus (+ which meniscus)?
-semitendinosus; lateral meniscus
-biceps femoris; medial meniscus
-semimembranosus; medial meniscus
-semitendinosus; medial meniscus
semimembranosus; medial meniscus
-EXPLANATION: as your hamstrings pull the tibia backwards, they are also pulling the meniscus backwards with the tibia
-this allows the tibia to stay between the tibia + femur to maintain its position + provide stability
what does the subtalar joint consist of?
-talus + navicular
-talus + calcaneus
-calcaneus + cuboid
-talus + cuboid
talus + calcaneus
-EXPLANATION: most of the motion occurring at this joint includes inversion + eversion
what is happening arthrokinematically during the eccentric phase of a squat in the tibiofemoral joint?
-the tibia rolls anteriorly + glides posteriorly on the femur; femur spins internally
-the tibia rolls posteriorly + glides anteriorly on the femur; femur spins externally
-the femoral condyles roll posterior + glide anteriorly on the tibia; femur spins externally
-the femoral condyles roll anterior + glide posterior on the tibia; femur spins externally
the femoral condyles roll posterior + glide anteriorly on the tibia; femur spins externally
-EXPLANATION: remember the convex vs convave rule + this is a closed chain exercise
-convex on concave: the roll + glide are in opposite directions
-closed chain: distal tibia is fixed
-external rotation due to screw home mechanism
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PALPATION EXAM103
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UE Mechanisms of Injury47
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Dr. Hayes- The Vertebral Column31
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Vertebral Column Function26
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Vertebral Column Structure41
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Dr. Hayes- Regional Variations in the Spinal Column40
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Trunk Structure + Function QUIZ6
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Regional Structure + Function of the Sacrum/Pelvis22
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Hip Biomechanics in SLS21
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Hip Biomechanics60
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Knee Joint69
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Tibiofemoral Movement27
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Patellofemoral Movement44
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Ankle-Foot Complex71
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Foot Function26
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Lower Extremity Structure + Function QUIZ9
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TA Session #423
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TA Session #524
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Exam 2 Practice Quiz8
