Week 5 The knee joint Flashcards
What are the acute injuries of the knee are presented to A&E?
Usually caused by Sports, fall, elderly
Fracture
Tear, sprain of ligament, soft tissue and cartilage
What acute swelling/pain can you get of the knee?
Acute gout or flare of osteoarthritis or rheumatoid arthritis
Septic joint
What are common caues of chronic knee pain/swelling?
Osteoarthritis or bursitis
What can severe damage of the knee cause?
Can result in reduction in movement, poor slep and reduced quality of life.
What type of joint is a knee joint?
Synovial hinge joint
What 3 bones are invovled in the knee joint?
Distal femur
Patella
Proximal tibia
What are the 3 articulations formed by the knee joint?
2 femorotibial –> lateral and medial
1 femorpatellar
Is the fibula part of the knee joint?
No it is not–> articulates with the tibia though
What are the expansions of the distal femoral called?
Lateral femoral condyle on the lateral side
Medial femoral condyle on the medial side
What does the lateral and medial femoral condyle articualte with?
They articualte with the lateral and medial tibial plateaus respectively of the tibia.
What are the movements of the knee joint?
Flexion
Extension
Medial rotation of leg when knee joint flexed 90 degrees
Lateral roation of leg when knee is flexed 90 degrees
When can knee roate?
Rotation can only occur when the knee is flexed and the collateral ligaments are relaxed
When do you loose some knee flexion?
When the pelvis is extended due to loss of tension on hamstring
what is locking of the knee?
As the knee joint aproaches full extension the femur undergoes few degrees of rotation on the tibia.
What is the effect of locking of the knee on the thigh muscles?
The locking of the knee is very stable and therefore allows the thigh muscles to relax
How is the knee joint unlocked?
The knee is unlocked by the popliteus muscle rotating the femur laterally
Where is the popliteal fossa and what is contained with in?
Is a space found at the back of the knee joint and contaisnt the popliteal artery
What are the slight expansions of the proximal tibia?
Medial and lateral tibial condyles
Is flexion or extension of the knee joint most stable? Explain why
Extension is most stable because the tibia and femur have the best fit –> most congruence
However in flexion there is least congruence –> why most injuries happen when knee is flexed
What deepens the plateaus?
The tibial plateaus are deepened by 2 plates of fibrocartilage – the menisci
Why are the tibial plateaus deepend?
The reason is because the flattened tibail pateaus are not a good fit for the femoral condyles .
By deepening them you are improving the fit
What sit he shape Meniscis?
2 C shaped wedges of fibrocartilage
What part of the menisci is thicker?
Thicker at the external margins
What are the functions of the menisci?
Increase joint congruency
Distribute weight evenly
Shock absorption
Assist in locking mechanism