Station 5: The Knee Flashcards
What is normal Knee Flexion ROM?
155 degrees
What might limit knee flexion
Tight hamstrings and quads
What is normal knee hyperextension ROM?
3 degrees
What is laxity?
When ligaments are loosest
When do knee ligaments have greatest laxity (looseness)?
30-40 degrees flexion
What are the intrinsic structures of the knee
ACL
PCL
Lateral and medial meniscus
Articular capsule
What is the meniscus made of?
Fibrocartilage
What are the actions of the knee?
Flexion/Extension and Abduction/Adduction
What plane of motion is the most common at the knee?
Sagittal plane - flexion/extension
What is the screw home mechanism?
Lateral rotation of the tibia on the femur during extension
If there is absence of rotation of the tibia during extension what might this mean?
Torn meniscus or patellofemoral dysfunction
Which way does the patella move during flexion of the knee
Medially
Starts moving laterally again at 130 degrees of flexion
What are the functions of the patella?
Anterior protection of the knee
Leverage for the quads
Shock absorption/dissipate force
Sliding reduces friction
What are some causes of abnormal patella tracking?
- muscle imbalance of knee muscles: vastus lateralis dominant to vastus medialis. Causes patella to sit more lateral than it should
- meniscus tear
- trauma injury
What is the Q-angle?
Position of the tibial tuberosity affects the line of pull of quad muscles and therefore the tracking of the patella
Measurement of the angle between the rectus femoris ligament and patella ligament
