lecture 6: therapeutic exercsies for the knee Flashcards
what is a large seasamoid bone in the quad tendon
patella
in the knee what ligaments provide anterior posterior stability
ACL and PCL
in the knee what provides medial lateral stability
MCL and LCL
what is the menisci connected it
connected to tibial condyle and capsule by coronary ligaments
each menisci are connected by what
trasnverse ligament
what is the medial meniscus firmly attached to the
joint capsule and MCL ,ACL , PCL and semimembranosus mm
what is the lateral meniscus attached to
PCL and popliteus tendon via capsule capsular connections
which ligament resist valgus force
MCL (sMCL primarily)
sMCL resists what
tibial ER at 30° flexion
when is the sMCL taut
at end range of flexion and extension
what are the 2 main bundles of the ACL
Anteromedial bundle (smaller)
Posterolateral bundle (larger)
{Intermediate bundle} (maybe
when is each anteromedial bundle and posterolateral bundle taut
anteromedial- flexion
posterolateral - extension
what is the function of the ACL
percent anterior translation of tibia
provide stability during tibial rotation
limit hyperextension
what becomes taut with IR and ER of tibia with the most notes at 30° flexion
ACL
in knee extension when ACL bundle provides restraint to rotational forces
posterolateral is taut
AMB is slack
in knee flexion when ACL bundle provides restraint to anterior translation
AMB is taut
PLB is slack
if the AMB is gone then there will be more anterior translation
what are the 2 bundles of the PCL
ALB (larger)
PMB
when is the ALB of the PCL taut and lax
taut in knee flexion
lax in knees extension
when is the PMB of the PCL taut and lax
Taut in knee extension
Lax in knee flexion
when is the PCL vulnerable to injury
to a posterior force to the proximal tibia when the knee is FLEXED
what is the main function of the PCL
resist excessive posterior translation of the tibia
what is the medial menisci attached to , what shape is it and is it mobile or not mobile
dMCL
Semimembranosus
Quadriceps
C shaped
not mobile
what is the lateral menisci attached to , what shape is it and is it mobile or not mobile
Popliteus
Quadriceps
Arcuate ligament
Circular Shaped
Mobile
what is the articulation of the patellofemoral joint
patella within femoral groove
how does the femur move not he patella in CKC
under the patella
how much does the patellofemoral joint more in relation to femorla condyle
7-8 cm
pertaining to patella tracking what happens as the knee extends
patella moves superiorly
what are some malaligment and tracking problems
Increased Q-angle
Short ITB
Weak hip abd/ER
Foot pronation
Lax medial patellar
retinaculum
Insufficient VMO?
Deficits in lateral aspect
of intercondylar groove
Pelvic Dysfunction
what is the normal knee ROM for extension and flexion
extensions: 0°
flexion: 135°
what is open packed and closed pack for the knee
open packed: 25° of flexion
closed packed: full knee extension
how much ROM is needed to make a full revolution on a bike
~110°
in CKC the patellar compression raised between what degrees of flexion
between 30-60°
during OKC when is there patellar compression
greatest joint reaction force is at 30°
how much tibia rotation is there for IR and ER
IR and ER is 20-30°
IR of the tibia causes what ligaments to become taut
AMB of ACL and sMCL
what wraps around what during IR of the tibia
ACL wraps around the PCL
during ER what stretches over what
ALC stretches over the lateral condyle
with the knee flexed what casues the ER of the tibia
TFL and BF
what provides a MR (unlock) from a full extension
popliteus
what does joint effusion of the knee lead to
inhibiton of the quadriceps
what does joint effusion results in during walking
low sustained quadriceps activator and prolonged hamstring activation
___ rupture can lead to bruising in the calf with
no significant joint effusion
PCL
in what position/activity is the patellofemoral join reaction forces the highest
deep squat
for every 1 lb of weight loss , there is a __lb reduction in knee load per step
4
what is the main knee extensor in the leg
quads
what does the quads do in closed chain activities
the quads control the amount of knee flexion , also causes knee extension thru reverse mm pull on th femur
in the erect posture , wehn the knee is locked , the quads does not need to function when the gravity line is where a
dallas anterior to the axis of motion
what is the qaud function in open chain activities
a strong contraction of the quad mms is required to overcome the physiological and mechanical disadvantages of the mm to complete the final 15° of motion
what is the main knee flexor in the knee
hamstrings
what does the hamstrings do in closed chain
can assist w knee extension by pulling on the tibia
what is the gastrocnemius main function at the knee
during WB is to support the posterior capsule against hyperextension forces (can also assist with knee flexion)
what mm supports the posterior capsule adn acts to unlock the knee (screw home mechanism)
popliteus
what is in the pes anserinus mm group
sartorius , gracilis , semtendiniosus
what is the function of the Pes anserinus muscle group (sartorius, gracilis, semitendinosus)
provides medial stability to the knee , affects rotation of the tibia in a closed chain
Lack of hip IR , hip flexion contracture and lack of ankle DF ROM can cause pain where
the knee
