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Flashcards in knee 6 Deck (30):
1

Name the 5 parts of the posterolateral capsular complex of the knee?

1. Popliteofibular ligament. 2. LCL. 3. Arcuate ligament. 4. biceps femoris tendon and tendon expansion. 5. Popliteus.

2

What will the posterolateral capsular complex of the knee resist?

anterior translation, hyperextension, varus stress, medial rotation and lateral rotation extremes.

3

How is the posterolateral capsular complex of the knee palpated?

In a figure 4 pattern.

4

What happens to the posterolateral capsular complex of the knee during knee flexion?

LCL- lax, PFL- tense.

5

What will happen when the LCL is lax?

This allows the tibia to undergo its normal internal rotation(conjoint rotation).

6

What will happen when the PFL becomes tense?

It doesn’t interfere with internal rotation; half as strong as the LCL.

7

What is more resistant to anterior translation stability the LCL or PFL?

PFL.

8

What is the order of ligament failure with increased carus stress?

LCL---> PFL----> popliteus and acruate ligaments.

9

What are the 2 cruciate ligaments?

ACL and PCL.

10

Where are the cruciate ligaments found at in general?

Intracapsular and extrasynovial (outer lining by synovial membrane).

11

What is the blood supply like to the cruciate ligaments?

they are relatively hypovascular however the synovial lining is highly vascular.

12

What is the significance of a highly vascular synovial lining of the cruciate ligaments?

If the ligaments rupture then bleeding would occure and this is calle dhemarthrosis.

13

Where will the anterior cruciate ligament attach to?

anterior tibial plateau and anterior tibial spine to the medial aspect of the lateral femoral condyle.

14

Which cruciate ligament is largest?

Posterior is largest.

15

What are the parts of the ACL?

1. Anterior band. 2. Posterior band.

16

What will the tension be like on the ACL during different positions?

Always tense. Since the anterior band is tense when knee is flexed and posterior band is tense when knee is extended.

17

The ACL is primaraly resistint to what?

anterior tibial translation.

18

Why will 3/4 of all knee hemarthrosis involve the ACL?

Because it supports the blood vessels of the femur.

19

What is the name of the test for tibial translation joint play?

Anterior drawer test.

20

Where will the PCL attach to?

Attaches to the lateral aspect of medial femoral condyle to posterio proximal tibia (NOT TO THE TIBIAL PLATEAU).

21

The PCL crosses _______ to the ACL.

Posteromedial.

22

Which ligament is stronger the ACL or PCL and by how much?

PCL is 2X as strong as ACL.

23

The PCL is also always tense but it is least tense when?

with 25-40 degrees flexion.

24

What are the parts of the PCL?

smaller anterior and larger posterior bands.

25

The PCL is pramarily resistant to what?

Posterior translation.

26

What is the gravity sag sign and what will it mean?

It is posterior sagging of tibia when supine/ knee bent postion and it is a tear of the PCL.

27

What is the most serious ligmaentous injury of the knee?

ACL.

28

Which Cruciate ligament will be less likely to require corrective surgery when torn?

PCL.

29

Why will the PCL be less likely to requrie surgery if torn?

Massive contribution of quadraceps.

30

What is the test for posterior tibial translation joint play?

Posterior drawer test.