Knee Joint

Question 1

what type of joint is the knee joint

Answer 1

hinge type of synovial joint

Question 2

what does the stability of the knee depend on

Answer 2

strength and actions surrounding muscles and their tendons

ligaments connecting the femur and the tibia

Question 3

articulations of the knee joint

Answer 3

lateral femorotibial articulation

medial femorotibial articulation

femoropatellar articulation

Question 4

lateral femorotibial articulation

Answer 4

b/w lateral condyles of the femur and tibia

Question 5

medial femorotibial articulation

Answer 5

b/w the medial condyles of the femur and tibia

Question 6

femeropatellar articulation

Answer 6

b/w the patella and femur

Question 7

articular capsule of the knee joint

Answer 7

consists of an external fibrous layer and internal synovial membrane

Question 8

internal synovial membrane

Answer 8

lines all internal surfaces of the synovial cavity not covered w/ articular cartilage

Question 9

ligaments of the knee joint

Answer 9

extra-articular ligaments (outside of the joint capsule)

intraarticular ligaments (“w/in the joint capsule”, outside the synovial membrane)

Question 10

extra-articular ligaments

Answer 10

patellar ligament (patellar tendon)

tibial (medial) collateral ligament (MCL)

fibular (lateral) collateral ligament (LCL)

oblique popliteal ligament

arcuate popliteal ligament

anterolateral ligament (ALL)

Question 11

tibial (medial) collateral ligament (MCL)

Answer 11

runs on the medial side

fibers that attach to the medial meniscus

prevents valgus stress

tears easily

Question 12

fibular (lateral) collateral ligament (LCL)

Answer 12

prevents varus stress

runs on the lateral side

cord-like and is very strong

reinforcement from the IT-band

Question 13

arcuate popliteal ligament

Answer 13

arc-like shape

posterior

extension of the semitendinosus

arches over the popliteus muscle

Question 14

anterolateral ligament (ALL)

Answer 14

origin: lateral femoral condyle and anterior to origin of LCL

insertion: b/w Gerdy’s tubercle and apex of fibular head

function: limit internal tibial rotation

Question 15

intra-articular ligaments

Answer 15

cruciate ligaments

ACL and PCL

Question 16

anterior cruciate ligament (ACL)

Answer 16

more anterior

runs from the posterior lateral femur to the anterior medial tibia

Question 17

want does the ACL help resist

Answer 17

anterior displacement of the tibia (prevents hyperextension)

posterior displacement of the femur

Question 18

posterior cruciate ligament (PCL)

Answer 18

more posterior of the two

runs from the medial femoral condyle to the tibia on the posterior intercondylar tibia

stronger than the ACL (less likely to tear)

Question 19

what does the PCL help resist

Answer 19

anterior displacement of the femur

posterior displacement of the tibia

Question 20

menisci of the knee joint

Answer 20

coronary ligament

transverse ligament of the knee

medial meniscus

lateral meniscus

posterior meniscofemoral ligament

Question 21

coronary ligament

Answer 21

attach the menisci to the tibial condyle

on the front edges of the menisci

Question 22

transverse ligament of the knee

Answer 22

joints the anterior edges of the menisci

Question 23

medial meniscus

Answer 23

creates a deeper socket for the femoral condyles (better bony congruency, increasing bony congruency)

more c-shaped

fibrocartilaginous structure

shock absorber

Question 24

lateral meniscus

Answer 24

more circular shaped

creates a deeper socket for the femoral condyles (better bony congruency, increasing bony congruency)

fibrocartilaginous structure

shock absorber

Question 25

posterior meniscofemoral ligament

Answer 25

strong tendinous slip that attaches to the PCL

Question 26

movements

Answer 26

flexion/extension (main movement)

some rotation occurs when the knee is flexed

Question 27

“locking” the knee

Answer 27

medial rotation of the femur on the tibia

makes the knee more stable for weight bearing

more movement on the medial side

Question 28

“unlocking” the knee

Answer 28

lateral rotation of the femur on the tibia

allows for knee flexion

Question 29

vascular elements of the knee

Answer 29

genicular anastomosis

middle genicular anastomosis

Question 30

genicular anastomosis

Answer 30

from femoral –> popliteal –> anterior and posterior recurrent branches of anterior tibial and circumflex fibular arteries

Question 31

middle genicular branches of the popliteal artery

Answer 31

penetrate the fibrous later of the joint capsule and supply

-cruciate ligaments
-synovial ligaments
-peripheral margins of menisci

not a good blood supply for the knee itself

Question 32

neural elements of the knee

Answer 32

articular branches from femoral, tibial and common fibular nerves

obturator and saphenous nerves

Question 33

bursae of the knee

Answer 33

at least 12 bursae around the knee joint

Question 34

subcutaneous prepatellar and infrapatellar bursae

Answer 34

located at the convex surface of the joint

allow the skin to be able to move freely during joint movement

Question 35

bursae that communicate with the articular cavity of the knee joint

Answer 35

suprapatellar bursa

popliteus bursa

anserine bursa

gastrocnemius bursa

Question 36

unhappy triad

Answer 36

includes the MCL, medial meniscus, and ACL

ACL has fibers that attach to the medial meniscus

MCL has fibers that attach to the medial meniscus

usually happens when the foot is planted and there is a laterally directed force (forces knee into valgus)