Knee muscles

Question 1

what is the knee locking mechanism in standing knee extension

Answer 1

• knee joint is Locked in closed pack position
• joint surfaces more congruent
• femoral condyle is longer anteriorly+posteriorly so continues to glide and locks in medial rotation
• popliteus initiates ‘unlocking’ by laterally rotating femur on fixed tibia and ‘locking’ by medial rotation

Question 2

what is the knee locking mechanism in sitting to standing

Answer 2

• femoral condyles roll anteriorly over tibial condyles
• femoral condyles glide posteriorly over tibial condyles
• shorter lateral femoral condyle movement stops first
• femur medially rotates around fixed lateral condyle to complete movement and spins until locked

Question 3

what is the knee locking mechanism in standing to sitting

Answer 3

• femur spins laterally on tibia
• femoral condyles roll posteriorly on the tibial condyles
• femoral condyles glide anteriorly on the tibial condyles and this stops femoral condyles from rolling off tibial condyles

Question 4

name the quadriceps muscles

Answer 4

rectus femoris
vastus medialis
vastus intermedius
vastus lateralis

Question 5

name the hamstring muscles

Answer 5

biceps femoris
semitendinosis
semimembranosis

Question 6

movements and degrees at knee joint and limits

Answer 6

flexion= 135 degrees
limit- soft tissue apposition, PCL

extension= 0, hyper e=0-5 degrees
limit- tension in antagonist, ACL, PCL

rotation in flexion
medial roation= 20-3- degrees
lateral rotation= 30-40 degrees
limits= tension in antagonist

Question 7

give knee flexion muscles and attachments

Answer 7

biceps femoris
semitendoinosis 
semimembranosis
sartorius
popliteus
gastrocnemius

Question 8

give knee extension muscles and attachments

Answer 8

rectus femoris
vastus intermedius
vastus lateralis
vastus medialis

Question 9

give knee medial rotation muscles and attachments

Answer 9

semitendinosus
semimembranosis
sartorius
popliteus

Question 10

give knee lateral rotation muscles and attachments

Answer 10

biceps femoris

Question 11

describe contents of the popliteus fossa

Answer 11

lateral border= biceps fem, lat head of gastrocnemius
medial border= semitendinosis, semimembranosis, medial head of gastrocnemius
floor= popliteal surface of femur
roof= fascia and skin

popliteal contents= popliteal artery and vein
common perineal and tibial nerve
lymph nodes and fat

Question 12

what is the pet anserines (goose foot)

Answer 12

semitendinosis
gracilis
sartorius

Question 13

what are the accessory movements at the patella femoral joint

Answer 13

longitudinal caudal excursion

med side glide, lat side glide

Question 14

what are the accessory movements at the knee joint

Answer 14

tibio femoral AP glide, PA glide (hands behind leg)

med side glide, lat side glide (head of fibula)