The Knee Part 1: Exam 3 Flashcards
What type of joint is the knee?
Hinge with rotational component
What stabilizes the knee?
- ligaments
- joint capsule
- muscles
What is the knee designed for?
Stability with weight bearing and mobility in locomotion
2 joints of the knee
- tibiofemoral
- patellofemoral
Bones in the tibiofemoral joint
- tibia
- femur
Actions of the tibiofemoral joint
- flexion and extension
- little rotation
Bones of the patellofemoral joint
- patella
- femur
Actions of the patellofemoral joint
-gliding
Appearance of the meniscus
Wedge
Shape of medial meniscus
C shape
Shape of lateral meniscus
O shape
Function of meniscus
- shock absorption
- stabilization
Extracapsular ligaments
-Medial Collateral Ligament
-Lateral Collateral Ligament
(Outside of capsule)
Intracapsular ligaments
-Anterior cruciate ligament (ACL)
-Posterior cruciate ligament (PCL)
(Inside capsule)
Tendons of the knee
- quadriceps
- patella (ligament)
Retinaculum
Connective tissue that holds down tendons
Where is the quadriceps group?
Anterior surface of the leg
4 muscles in the quads group
- rectus femoris
- vastus medialis
- vastus lateralis
- Vastus intermedius
What do these 4 muscles feed into?
One tendon
What is the quad group responsible for?
Knee extension
Where is the hamstring group?
Posterior surface of the leg
What is the hamstring group responsible for?
Knee flexion
What are the 3 muscles of the hamstring group?
- Bicep femoris (lateral)
- semitendinosis (medial)
- semimembranosus (medial)
What is critical in assessing a knee injury?
Determining the mechanism of the injury
Observing a knee injury
- walking, squatting, going up and down stairs
- swelling, ecchymosis
- leg alignment
- knee symmetry
- leg length
tests for the knee
- manual muscle tests
- special tests
- neurological
Special tests for the knee
- joint stability
- ligament
- meniscus
Neurological tests
- sensation
- foot drop
- reflexes
Translation
Refers to the glide of tibial plateau relative to the femoral condyles
What does knee laxity include?
Straight and rotary instability
What increases as the damage to stabilizing structures increases?
Laxity and translation
Special tests for knee instability
- use endpoint feel
- MRI
- Classification of joint instability
Q-angle
Lines which bisect the patella relative to the ASIS and the tibial tubercle
What is the normal Q-angle for females?
15 degrees
Normal Q-angle for males
10 degrees
What can elevated angles lead to?
Pathological conditions associated with improper patella tracking
