The Knee Joint Flashcards
What is the function of the patella?
Enhances the leverage that quadriceps tendon can exert on femur to aid extension.
Protects anterior knee from trauma.
Why are patellar dislocations more common in females than males?
Females have larger Q angle, central pull of quads is stronger. (Q angle = angle of femur coming into knee females have wider pelvis so larger angle).
What is ‘housemaids knee’?
Prepatellar bursitis caused by long periods of kneeling.
What is the role of the menisci?
Improves congruity to increase stability of joint
In which position is knee most unstable?
Flexion -least congruence.
What is the origin, insertion and main function of the ACL?
O: anterior intercondylar region of tibia
I: lateral femoral condyle
F: prevents posterior dislocation of tibia
What is the origin, insertion and main function of the PCL?
O: posterior intercondylar region of tibia
I: medial femoral condyle
F: prevents anterior dislocation of tibia
How are the cruciate ligaments typically injured?
hyperextension of knee
large force when knee flexed
What is the origin, insertion and main function of the MCL?
O: medial femoral condyle
I: medial tibia
F: prevents medial displacement
What is the origin, insertion and main function of the LCL?
O: lateral femoral condyle
I: lateral surface of fibular head
F: prevents lateral displacement
How are the collateral ligaments usually injured?
Force applied to side of knee when foot on floor. Lateral most commonly injured.
How do the collateral ligaments differ in appearance?
Medial = wide and flat, lateral = thin and round
Which muscles are flexors of the knee?
Hamstrings, sartorius, gracilis, popliteus
Which muscles are extensors of the knee?
Quadriceps
How does popliteus aid flexion?
Begins flexion by laterally rotating femur on tibia to unlock knee. Locked position = femur medially rotated.
