Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy Week #3 > Knee > Flashcards

Knee Flashcards

1
Q

Describe the articular surfaces of the knee joint.

A

-medial condyle extends farther inferiorly and laterally
-lateral condyle projects farther anteriorly
tibia
-medial condyle is larger to match femur condyle
patella
-larger lateral facet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the 2 articulations of the knee

A
  • tibiofemoral: poor congruence so increased number of ligaments and fibrocartilage to stabilize it
  • patellaofemoral: good congruence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where does the synovial joint capsule attach? When is it taut/loose?

A
  • about 1 cm away from articular border

- in flexion, anterior portion is taut and in extension, posterior portion is taut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the synovium of the knee?

A

-it invaginates the articular surfaces and does not include the ACL and PCL (so not nourished by synovial fluid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where are the 4 bursae in the anterior knee? 3 in posterior knee?
What is their function?

A
  • prepatellar: between skin and patella
  • suprapatella: deep to quadraceps tendon
  • deep infrapatellar:b/w patellar ligament and tibia
  • subcutaneous infrapatellar: b/w skin and patellar ligament
  • posterior are behind muscle bellies and tendon attachments
  • reduce frictional and compressional stresses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the function of the knee menisci?

A

1) improve bone congruency
2) assist in arthrokinematics
3) increase SA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe the structure of the knee menisci and all the ligaments surrounding them.

A
  • lateral edges are taller and highly vascularized
  • medial edges attach to intercondylar eminence and are not as vascularized

coronary (attach menisci to tibia)
transverse (attach anterior surfaces of both meniscus)
intercondylar (attach meniscal horns to intercondylar eminence)
posterior meniscofemoral (attach posterior horn of lateral meniscus to medial femoral condyle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe meniscal movement

A
  • in flexion, menisci move posteriorly
  • in extension, menisci move anterior
  • the lateral meniscus has more movement, because the medial meniscus is attached to the medial side of the joint capsule and medial collateral ligament
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What reinforces the knee anteriorly (in flexion)?

A

extensor mechanism reinforces knee in flexion

  • patella
  • patellar ligament
  • quadriceps
  • quadriceps tendon
  • patellar retinacula (medial/lateral side of patella lig’t)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What reinforces the knee medially? And describe its location and what type of action it resists.

A
  • MCL (medial collateral ligament)
  • runs from the medial epicondyle of femur to the medial aspect of the proximal tibia
  • thickening of the joint capsule and blends with medial meniscus
  • resists valgus loading (hit laterally and femur adducts/tibia abducts)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What reinforces the knee laterally? Describe their location and what type of action they resist.

A

LCL (lateral collateral ligament)
extracapsular/extrinsic lig’t; runs from lateral condyle posteriorly to the fibular head, under the biceps femoris attachment
-resists varus loading (hit medial and femur abducts/tibia adducts)
Iliotibial band formed by TFL/glut max fascia and inserts in to lateral tibial condyle
-resists varus loading and tibial IR
-a dynamic ligament- muscle tendon unit that when active acts like a ligament to support the joint
-when knee is extended, the IT band is anterior to axis of rotation and is knee extensor, and vice-versa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What reinforces the knee posteriorly? Describe their location and what type of action they resist.

A

oblique popliteal ligament
-runs from lateral condyle femur to medial condyle of tibia
arcuate ligament
-triangular pattern from lateral condyles of femur and tibia and head of fibula and also limits varus
-both limit extension/hyperextenstion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What characteristics do the ACL and PCL share?

A
  • intrinsic ligaments, but extrasynovial

- poor vascularization but extrasynovial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe characteristics of the anterior cruciate ligament: where it runs, unique factors, what it resists

A
  • runs from the medial aspect of the lateral femoral condyle to the anterior intercondylar fossa
  • well innervated, so can’t reproduce proprioception given by ligament when have surgery
  • resists anterior tibial translation and IR tibia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe characteristics of the posterior cruciate ligament: where it runs, unique factors, what it resists

A
  • run from intercondylar surface of the medial femoral condyle to the posterior intercondylar fossa; runs w/ meniscofemoral ligament
  • resists posterior translation of tibia or anterior translation of femur
  • least effect at 70-90 degrees flexion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the screw-home mechanism? What structures play a role in it?

A
  • femur rotates medially in full extension because of lateral femoral condyle is more anterior and “locks” knee joint so less muscles needed to be recruited to stand
  • popliteus muscle rotates femur laterally to unlock the medial rotation in knee flexion
17
Q

What is the patella embedded in and what does it articulate with?What is the patellar facet angle of the patellofemoral joint and the significance of smaller/larger angles? Which facet is larger?

A
  • embedded in the quadriceps tendon
  • articulates w/ the trochlea groove of femur
  • 138 degrees average, smaller angle means less movement w/i trochlear groove
  • lateral facet is larger
18
Q

Why is the lateral femoral condyle more anterior than the medial femoral condyle?

A

the patella will tend to be pulled laterally when the quads contract, so the lateral femoral condyle is longer to absorb more of the force

19
Q

What is the implication of the superior aspect of the trochlear groove being more shallow?

A

when the patella rides high on the femur, it is more likely to move outside of the groove

20
Q

Why do we have a patella?

A
  • increases the lever arm from axis of rotation to muscular effort, to increase torque
  • increases SA, so it can distribute the force of the quadriceps across the femur and decrease compressional stress
21
Q

What is patella alta?

A

when patellar ligament is too long (1.3x quad tendon), the patella rides too high in the trochlear groove and has increased mobility

22
Q

What is the Q angle and its implications?

A
  • angle of intersection b/w shaft of tibia and shaft of femur
  • angle of intersection b/w line from ASIS to patella and tibial tuberosity to patella
  • a larger Q angle gives us a larger pull laterally at the patella

Anatomy Week #3 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions