Movements of the Knee

Question 1

What are the 5 movements of the knee?

Answer 1

1. flexion
2. extension
3. internal rotation
4. lateral rotation
5. locking/unlocking

Question 2

What muscle group primarily flexes the knee?

Answer 2

hamstrings

semitendinosus, semimembranosus, biceps femoris, Sartorius, gracilis (weakly)

Question 3

What limits knee flexion?

Answer 3

soft tissue between calf and thigh

Question 4

What muscle group primarily extends the knee?

Answer 4

quadriceps

rectus femoris, vastus lateralis, vastus medialis, vastus intermedius

Question 5

What limits extension in the knee?

Answer 5

cruciate (ACL, PCL) and collateral ligaments

Question 6

What internally rotates the knee?

tiba on femur, the point of reference for rotation of the knee is the TIBIA!

Answer 6

semitendinosus, semimembranosus, sartorius, popliteus.

Question 7

What checks internal rotation of the knee?

Answer 7

cruciate ligaments (ACL & PCL)

Question 8

What externally rotates the knee?

tiba on femur, the point of reference for rotation of the knee is the TIBIA!

Answer 8

biceps femoris

Question 9

What checks external rotation of the knee?

Answer 9

collateral ligaments

Question 10

When the knee is extended while standing, the knee passively “locks” by internally rotation of the femur on the tibia (same as external rotation). In the locked position, muscles can relax without making joint too unstable. To unlock the knee, the femur externally rotates so that flexion can occur. What muscle does this?

Answer 10

popliteus