knee joint

ACL

anterior tibia posterior femur restrains hypertension mechanism of injury

q angle

asis to center of patella (line of pull for entire quadriceps) runs fromcenter of patella to center of tibial tuberosity (pull of patellar tendon) males 10-15 females 15-20

sagittal plane

axis patella anterior posterior flexion and extension

transverse plane

axis tibial tuberosity medial lateral external rotation internal rotation

recurvatum

back knees

varum

bow legged

popliteus

contracts unlock knee tibiofemoral joint allowing knee to flex from full extension

When looking at the femur, you notice that the ______ _______ is ______ and extends more ________ than the _______ one.

distal femur medial laterally

extension and flexion

extension 0 deg hyperextension 10 deg or more flexion about 140 deg

The knee joint is the largest joint in the body and one of the most complex. It is also one of the most commonly injured joints due to the torque experienced as a result of the two long bones articulating: the _____ and the _____.

femur tibia

scew home

fully extend shape of medial femoral condyl tension in anterior cruciate li lateral pull of quads (for external rotation and extension)

patella functions (5)

improve effciency and increase torquw for knee extensors centralize the forces o2f the four quadriceps provide smooth gliding mechanism for quadriceps muscle and tendon to reduse compression contribute to stability provide bony protection from trauma to femoral condyles when knees flexed

infrapatellar fat pad

posterior patellar tendon insertion point for synovial folds of tissue (plica) an anatomical variant that may be irritated or inflamed with injuries or overuse of the knee

PCL

posterior tibia anterior femur strongest lig restrains hyperflexion

patellectomy

removal of patella

joints of knee

tibiofemoral patellofemoral tibiofibular (not in knee joint capsule)

When considering the knee joint, we discuss two joints: the _____________ joint and the _______________ joint. There is another joint in this area that lies outside of the knee joint capsule called the _________ _____________ _____ but it has limited function with the knee as the _______ and the _______ have no direct articulation. This joint will be discussed more when we cover the ankle.

tibiofemoral patellarfemoral

unhappy triad

torn MCL and ACL

A third bone seen in this joint is the _______. The ________ is the largest ________ bone in the body. In general, _________ bones are ____- _________ bones that lie within a ______ and they function to protect the tendon and change the tendon's _____ __ ____. The _______ is shaped like an ________ ________ with the ____ at the bottom and the ____ on the top. It is located in the __________ tendon at the _________ ______. We name the part of the tendon _______ to the _______ the __________ tendon while we call the tendon ______ to the _______ the ________ ______.

patella patella seasamoid tendon angle of pull patella inverted triangle apex at top base at bottom patellar ligament center

patellofermoral joint

patella moves inferiorly during flexion patella moves superiorly during extension

bursae

10 around knee and in connected tissue

knee joint function

2 degrees of freedom flexion, extension rotation (20-30 of flexion)

LCL

Maintains lateral stability femur to fibula

Patella

Sesamoid bone imbedded in quadriceps and patellar tendon apex (bottom, inferior) Base (top, inferior)

fibiofibular joint

The proximal tibiofibular joint is a synovial joint that functions in dissipating lower leg torsional stresses and lateral tibial bending moments and in transmitting axial loads in weight-bearing

rotation

knee is flexed 20-30 degrees internal 30 deg (leg laterally away from midline) external 40 deg (leg medially toward midline)

valgum

knock knees

meniscus

lateral medial Deepen joint socket Improve joint congruency-stability Ability to distribute forces of impact Promote joint lubrication Prevent joint capsule from intruding on joint space Partial protection from knee hyperextension Injury Mechanism

patella bja

lower patella

MCL

maintains stability femur to tibia, medial meniscus

synovial cavity

supplies knee with synovial fluid lies under patella and between surface of tibia and femur

patella alta

upper patella