knee 7

Question 1

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

Answer 1

Twist- internal rotation. Untwist- external rotation.

Question 2

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

Answer 2

Increased twisting and increased stress.

Question 3

What is the 3 column therory of rotational stability ?

Answer 3

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

Question 4

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

Answer 4

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

Question 5

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

Answer 5

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

Question 6

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

Answer 6

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

Question 7

What is the secondary stabilizers of the knee?

Answer 7

Dynamic stability of muscle contractions.

Question 8

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

Answer 8

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

Question 9

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

Answer 9

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

Question 10

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

Answer 10

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

Question 11

What muscle is most importatn to the patellar stability?

Answer 11

vmo

Question 12

What muscle is reflexivley faster the VMO or the VL?

Answer 12

vmo

Question 13

Which muscle will atrophy faster the VMO or the VL?

Answer 13

vmo

Question 14

What is the priamry and seconary stabilizer for anterior translation?

Answer 14

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

Question 15

What is the priamry and seconary stabilizer for posterior translation?

Answer 15

1- PCL, quads and popliteus.

Question 16

What is the priamry and seconary stabilizer for valgus?

Answer 16

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

Question 17

What is the priamry and seconary stabilizer for varus?

Answer 17

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

Question 18

What is the priamry and seconary stabilizer for flexion?

Answer 18

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

Question 19

What is the priamry and seconary stabilizer for extension?

Answer 19

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

Question 20

What is the priamry and seconary stabilizer for medial rotation?

Answer 20

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

Question 21

What is the priamry and seconary stabilizer for lateral rotation?

Answer 21

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

Question 22

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

Answer 22

Anterolateral rotational.

Question 23

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

Answer 23

Anteromedial rotational.

Question 24

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

Answer 24

Posteriolateral rotational.