Flashcards in Lecture 9.1 Deck (32):
What joints are present in the knee complex?
Patellofemoral, tibiofibular, and tibiofemoral joints
What kind of joint is the knee joint?
Knee joint is a compound joint and a hinge joint
Is the knee joint weightbearing?
Yes weight of the body goes directly anterior to the knee joint but the knee carries a lot of the weight.
How does the knee joint deal with its poor congruence?
2 Menisci are prescent on the tibia which holds the femur in a socket.
What is the function of the articularis genus muscle?
This muscle pulls away the synovial membrane from the way of the patella to prevent impingement
What structures are present within the fibrous capsule of the knee?
The patella, menisci, ligaments, and bursae.
What deficiencies does the fibrous capsule contain?
Anteriorly the suprapatellar bursa
Posteriorly the popliteal tendon.
What is the origin and insertion of the popliteus muscle?
originates at lateral surface of the lateral condyle of the femur.
Inserts at proximal posterior surface of the tibia.
What structures reinforce the knee articular capsule?
Patellar ligament and retinaculae anteriorly.
oblique arcuate ligaments posteriorly.
LCL and ITB laterally
Coronary ligaments inferiorly.
many muscles also support the capsule
What is significant about the synovial membrane of the knee joint?
Knee joint contains largest synovial membrane in the body.
What structures does the synovial membrane contain?
Popliteus tendon, cruciate ligaments, and infrapatellar fat pad.
What bursae communicate with the knee joint?
suprapatellar, popliteus, and semimembranosus.
What bursae is named as the housemaid's bursa?
Which infrapatellar bursa is more likely to be inflamed?
The deep infrapatellar bursa
What are the ligaments of the knee?
oblique popliteal ligament
arcuate popliteal ligament
transverse genicular ligament
What is the function of the transverse genicular ligament?
prevents anterior movement of the anterior horns of the menisci.
What are the functions of the menisci?
Improve congruency and stabilize the knee.
Increases contact area by 1/3
Bears weight and protects articular surfaces
spreads synovial fluid
allow for locking and unlocking to take place
What separates the menisci?
the popliteal tendon
What test can be used for ACL and PCL injuries?
anterior and posterior draw test
What is conjunct and adjunct rotation?
conjunct rotation is the rotation that takes place during locking and unlocking.
adjunct rotation is rotation of a flexed knee via hamstrings
Is conjunct rotation active or passive?
locking is passive but unlocking is active and performed by the piriformis.
What direction is rotation during locking?
locking involves internal rotation of femur on tibia
What is the knee's blood supply?
the genicular branches of femoral popliteal artery form anastomoses around the knee
What is the knee's nerve supply?
HIlton's law; branches of obturator, femoral, and sciatic nerve
What is genu valgum and varum?
Genu valgum occurs when the lateral condyles of the legs touch each other and the knock-kneed position.
Genu varum is the opposite.
What is the function of the patellofemoral joint?
gives the vastus muscles more leverage. at start of extension it is a hindrance but then the leverage becomes a good thing.
What is the tracking of the patella?
tracking is the lateral orientation of the patella.
What factors prevent dislocation of the patella?
orientation of the vastus medialis
medial patella retinaculum
raised lip on lateral femoral condyle
Is the proximal tibiofibular joint intra or extracapsular?
What kind of joint is the proximal tibiofibular joint?
plane synovial joint which allows only gliding.
What ligaments support the distal tibiofibular joint?
Anterior, posterior, and interosseus ligaments