The Knee Complex

Question 1

Tibio Femoral Joint

Answer 1

1 DOF
ext/flx 0-135 deg
Rotary degree

Question 2

tibiofemoral end feels

Answer 2

flx -soft
ext-firm

Question 3

what defines the tibiofemoral double condyloid joint?

Answer 3

the medial and lateral articular surfaces

Question 4

Femur

Answer 4

bicondylar, CONVEX

Question 5

Q angle

Answer 5

normally 10-15 deg

as Q angle increases comprssion forces in the vastus lateralis will increase risk for lateral dislocation

forms a line connecting the ASIS to midpoint of patella, as well as midpoint of patella to tibial tuberosity

Question 6

genu valgum

Answer 6

Increase in Q angle
compression laterally

Question 7

genu varum

Answer 7

decrease in Q angle
compression medially

Question 8

genu recurvatum

Answer 8

knee extension greater than 5 deg

can be due to muscle imbalances, systemic hypomobility, previous injury, nuerological deficit

Question 9

What is the function of the cartilage support in the tibiofemoral joint ?

Answer 9

distribute the load

reduce friction between the tibia and the femur

Question 10

medial meniscus

Answer 10

C shaped

Question 11

lateral menisicus

Answer 11

4/5 of a circle

Question 12

Surgeons “red zone”

Answer 12

external 1/3 recieves highly vascularized

surgical repair has high likelihood to heal

Question 13

MCL

Answer 13

primary restraint to excessive valgus

is pulled taut in extension
given slack in flexion

Question 14

LCL

Answer 14

primary restraint to excessive varus

attatches to fibular head
is pulled taut in extensions
slackened in flexion

Question 15

ACL

Answer 15

primary restraint against anterior translation of tibia on the femur

taut in extenson

Question 16

What muscle may resist anterior translation of the tibia?

Answer 16

Hamstrings

Question 17

PCL

Answer 17

primary restraint to posterior displacement of the tibia on the femur

taut in flexion

Question 18

IT Band

Answer 18

an extension of the TFL and gluteus maximus

function: passive lateral support to the knee

Question 19

Patella

Answer 19

flat triangular shaped bone embedded with the quadriceps tendon

largest sesamoid in the body

function: an anatomical pulley for the quadriceps muscle

Question 20

What motions can the patella do?

Answer 20

medial and lateral shift
media and lateral tilt
medial and lateral rotation

Question 21

full extension

Answer 21

only the inferior pole of the patella makes contact with the femur

20 deg

Question 22

patella and femur relation during flexion

Answer 22

as flexion continues the contact area between the two moves superiorly and laterally

Question 23

full flexion

Answer 23

only the lateral and odd facets are making contact with the femur

Question 24

In open kinetic chain what is the kinematics of the tibiofemoral joint

Answer 24

concave on convex

Question 25

In closed kinetic chain what is the kinematics of the tibiofemoral joint

Answer 25

convex on concave

Question 26

closed chain flexion

Answer 26

posterior roll with anterior glide

Question 27

closed chain extension

Answer 27

anterior roll with posterior glide

Question 28

screw home mechanism

Answer 28

occurs in last 20-30 deg of knee extension an integral rotation to achieve full knee extension for stability of the joint

Question 29

Initiation of knee flexion

Answer 29

tibia IR femur ER

Question 30

Completing knee extension

Answer 30

tibia ER femur IR

Question 31

Medial rotators of the knee

Answer 31

politeus semimembranous semitendinous sartorius gracilis

Question 32

lateral rotators of the knee

Answer 32

biceps femoris

Question 33

Knee extenstors

Answer 33

rec fem crosses two joints not all fibers are oriented in same direction

Question 34

what is the function of the patella?

Answer 34

lengthens the moment arm of the quads to increase distance of quadriceps tendon and patellar tendon of the knee joint

Question 35

when is peak torques of the knee observed?

Answer 35

45 to 60 deg of knee flexion

Question 36

patellofemoral pain syndrome

Answer 36

most accurate test is to reproduce the symptoms of squatting ex. stair climbing and kneeling

Question 37

what are the 4 types of patellofemoral pain syndrome

Answer 37

1. overuse 2. PFP with muscle performance deficits 3.PFP with movement cord deficits 4.PFP with mobility deficits

Question 38

Bursitis

Answer 38

a direct blow or prolonged compressive or tensile forces

Question 39

chondromalacia patella

Answer 39

cartilaginous changes seen on lateral surface of patellar facet debated to be the same as PFP they say cartilage is aneural, thus damage may extend beyond that tissue articular cartilage

Question 40

What does genu recurvatum cause

Answer 40

compensatory lumbar lordosis

Question 41

What part of the meniscus heals best

Answer 41

outer