medial fem condyle to upper tibia posterior and pens anseranus
MCL ant fibers are seperate from ___, post fibers blend w___, superficial band blends w ___
- the capsule
- border of the medial meniscus
- posteromedial corner of the capsule / post. oblique lig
posteromedial corner of the knee's joint capsule is referred to as the
posterior oblique ligament
- lat aspect of lat condyle to head of fibula
- it's free of the capsule
arcuate ligamentous complex is a combo of what 4 items? what does it prevent?
LCL, biceps femorus, IT band, popliteous
ant intercondylar fossa of the tibia --> internal aspect of lat condyle ... runs sup, post, lat
ACL takes what percent of the load with ant translation in the extended knee?
ACL and PCL rel to capsule and synovium
they're intracapsuar, but extra synovial due to attachment to tibia. Though extrasynovial at tibia, as they go to femur they enter synovium and get a very rich vasuclar supply there bc they're bathed by synovial fluid
mechanoreceptors in ACL and PCL
they have some, so if you tear them you lose sense of where knee is in space
where is the ACL maximaly taut?
at 0-20 and 70-90 degrees flexion
ACL's anteromeial band (AMB) and posterolateral band (PLB) - when are they taut and lax?
- AMB: lax in ext, max taut at 70 degrees flex
- PLB: taut in ext, lax at 70
so, max excursion is at 30 degrees bc neither are taut there
- post part of posterior intercondylar fossa of tibia and post rim of upper tibia --> lat surface of med condyle
- runs med, ant, sup
bands in the PCL in ext and flex
- AMB or ant lat band: lax in ext, max taut at 80-90 flex
- PLB or post md band: taut in ext, relaxed at 80-90
like with the ACL, the ant band is relaxed in ext, and the post is taut in ext
rel of capsule to cruciate ligs, and length rel of PCL to ACL
- they're considered thickenings o the casule
- PCL is 3/5ths height of ACL
pos of ACL and PCL when keen is in flexion
- PCL is vertical
- ACL is horizontal
what do cruciates do to fem condyles?
pull back on them, making thm side on the tibial plateau in the direction opposite to the rolling motion
during flexion, the ACL moves the femur how and where? same qs for the PCL in ext?
- flex - acl makes the femur slide ant
- ext - pcl makes the femur slide post
how does the semiembranosus muscle affect the capsule?
its tendinous expansion, known as the oblique popliteal ligament reinforces the posteromedial aspect of the capsule
arcuate popliteal (arcuate) ligament supports what aspect of the capsule?
medial rotation does what to the collateral and cruciate ligs?
- relaxes the collateral ligs
- tightens the cruciates
lateral rotation dos what to the collateral and cruciate ligs?
- tightens the colatrals
- relaxes the cruciates