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Flashcards in knee 7 Deck (24):
1

When will the cruciate ligaments twist around each other and then when will they untwist?

Twist- internal rotation. Untwist- external rotation.

2

Injury to the ACL increases pronation and this leads to what?

Increased twisting and increased stress.

3

What is the 3 column therory of rotational stability ?

There are three columns of rotational stability of the knee the central, medial and lateral.

4

What things are in the central column and what motions will they resist?

ACL and PCL and they resist primarily AP translation and secondary resists medial rotation.

5

What things are in the medial column and what motions will they resist?

Semimembranosis, posterior MCL and oblique popliteal. Primarily resists lateral rotation secondarily resists translation.

6

What things are in the lateral column and what motions will they resist?

Biceps femoris, PFL, Acruate, and popliteus. Primarily resists medial rotation, secondarily resists translation.

7

What is the secondary stabilizers of the knee?

Dynamic stability of muscle contractions.

8

What will happen to the knee with isometric contraciton during a sustained squat?

about 60% decrease in rotational laxity and about 300% increase in joint stiffness.

9

What is the difference between closed and open chain with the knee complex?

Closed- increases co-contraction compared with open chain (increased velocity ---> increased con-contraction of antagonists).

10

what is the difference between quads and hams with slow and fast contraction?

Q:H slow 60:40. Fast- 10:9

11

What muscle is most importatn to the patellar stability?

vmo

12

What muscle is reflexivley faster the VMO or the VL?

vmo

13

Which muscle will atrophy faster the VMO or the VL?

vmo

14

What is the priamry and seconary stabilizer for anterior translation?

1- ACL, PFL. 2- hams and ITB.

15

What is the priamry and seconary stabilizer for posterior translation?

1- PCL, quads and popliteus.

16

What is the priamry and seconary stabilizer for valgus?

1- MCL. 2- Medial retinaculum, poplteus, medial hams and pes anserine.

17

What is the priamry and seconary stabilizer for varus?

1- LCL. 2- lateral retinaculum, ITB, and biceps tendon.

18

What is the priamry and seconary stabilizer for flexion?

1- quadraceps (no ligaments). 2- ?.

19

What is the priamry and seconary stabilizer for extension?

1- ALL and cruciate ligaments. 2- hams, gastroc, popliteus.

20

What is the priamry and seconary stabilizer for medial rotation?

1- cruciates and posterior capsule. 2- lateral retinaculum, ITB, Biceps tendon.

21

What is the priamry and seconary stabilizer for lateral rotation?

1- collaterals and posteriomedial capsule. 2- medial retinaculum, poplieus, medial hams and pes anserine.

22

Damage to the ACL and lateral complex will lead to what type of instability?

Anterolateral rotational.

23

Damage to the ACL and medial complex will lead to what type of instability?

Anteromedial rotational.

24

Damage to the PCL and lateral complex will lead to what type of instability?

Posteriolateral rotational.