Week 5 - The Knee

Question 1

what are the 3 articulating bones of the knee. What are the two joints?

Answer 1

Tibia
Femur
Patella

Tibiofemoral joint (the knee)
Patellofemoral joint

Question 2

What the 6 knee ligaments?

Answer 2

ACL PCL
LCL MCL
L Meniscus, M Meniscus

Question 3

What are the Menisci for?

Answer 3

Provide knee joint w stability, lubrication, shock absorption. Medial meniscus and medial collateral ligaments are attached to each other.

Question 4

What is the patella?

Answer 4

Sésamo id bone
Imbedded in quadriceps and patella tendon
Protects anterior knee structures from trauma
Acts as a lever, inc lever arm of the quadriceps.
Inc torque of quads by inc distance from axis of motion.
10-30% contribution to quadriceps torque. More in extension.

Question 5

4 quads, 3 hams

Answer 5

Rectas femora’s
Vastus - medialis, intermedius, lateralis

Biceps femoris
Semi - tendinosus, membranosus

Question 6

Other knee flexors

Answer 6

Gastrocnemius
Popliteus
Sartorius
Gracilis

Question 7

Explain Kinesiology of Biarticular Muscles.

Answer 7

When a muscle w multiple joint actions is activated it attempts to shorten and pull the original muscle closer to insertion.
Therefore it applies = force at O and I generating a torque at both joints. Attempting to perform all of its actions.

Question 8

What are the malalignments of the knee?

Answer 8

male 12-13 degrees
Female 16-18 degrees

Question 9

What is chondromalacia patella (runners knee)

Answer 9

Mist racking of patella and damage to patellofemoral cartilage
Risk factors:
Gene Valgum (high Q angle)
Pronation
High patella
Weak vastus medialis

Question 10

How does an ACL rupture occur?

Answer 10

70% of all ACL injuries are non contact - result from excessive anterior tibial translation
From video review of injuries:
-Typically occurs in cutting or landing movements
-relatively extended knee joint position
- Often with some knee valgas
_ internal rotation of the tibia
- Often very soon after ground contact.