Knee Joint Flashcards
What is the unhappy triad?
Medial collateral ligament
Medical meniscus
ACL
Why is the white zone of the menisci white?
It’s avascular
What is contained in the intercondylar notch?
The ACL
Which tendons reinforce the capsule medially?
The pes anserinus
Which movements does the ACL resist?
Femur posterior in relation to the tibia
Tibia anterior in relation to the femur
When is the patella more likely to be pulled laterally?
When the vastus medialis is weak
Which bones articulate in the knee joint?
Femur-Patella
Femur-Tibia
Is the patella inside or outside the knee joint?
Inside
What does the medial colateral ligament blend with?
Capsule
Medical meniscus
Which structures constitute the pes anserinus?
Sartorius
Gracilis
Bursa
Semi-Tendinosus
(Say grace before tea)
What is the name of the muscle required for initiation of unlocking?
Popliteus
Are the ligaments tight in extension or flexion?
Extension
What is Baker’s Cyst?
Inflammation of the bursa deep to the popliteus muscle
What are the three support structures at the knee joint?
The collateral ligaments
The cruxiate ligaments
The menisci
What is the origin and insertion the ACL?
Anterio-medial aspect of tibia to the posterio-lateral aspect of the femur
Which ligament is at risk in a bumper bar impact (where the tibia is impacted on)
PCL
What is the function of the menisci?
Shock absorption
Weight distribution
Which movement does the PCL resist?
Tibia posterior in relation to the femur
Femur anterior in relation to the tibia
In what position can rotation occur?
Flexion
Why isn’t the lateral collateral ligament damaged as much?
It’s separated from the meniscus by the popliteus muscle
Whhen is the ACL at particular risk?
When a laterally rotating force is apply against the passive locking medial rotation of the femur
What is the origin and insertion of the PCL?
Posterio-lateral aspect of tibia to the anterio-medial aspect of femur
How does the articular surfaces of the femur and tibia differ?
The femur has a rounded condyle while the tibia has a flat plateau
Which condyle of the femur is longer?
The medial one
Around what axis does the femur lock and unlock?
ACL
What is useful about the suprapatella bursa?
Expansion of it is a clinical sign of effusion of synovial fluid
Infectious material can enter the joint through it
What is the direction of pull of the popliteus?
Pulls the femur from tibia
Which movements does the medial collateral ligament resist?
Abduction and lateral rotation of the tibia
Anterior displacement of tibia
Are the menisci and cruciate ligament intrasynovial and intracapsular?
No, only intracapsular
Which menisci is more commonly injuried?
Medial
What knee position is valgus?
Force on the lateral side of the knee and feet outwards
Knocked knees
What knee position is varus?
Force on the knee medially
Feet are inwards
Bow legged
