Unit 4 Knee

Question 1

Femur Function

Answer 1

• Transmits force from pelvis through knee

Question 2

Tibia Function

Answer 2

• Weight baring

Question 3

Fibula Function

Answer 3

• Rotational stability

Question 4

Patella Function

Answer 4

• Increase force production at joint

Question 5

Joints of Knee

Answer 5

• Femorotibial
• Patellofemoral
• Tibiofibular (proximal/superior)

Question 6

Knee Joint

Answer 6

• Combination of femorotibial & patellofemoral joints
• Shared joint capsule

Question 7

Knee Functions

Answer 7

• Transition zone (connects thigh to shank)
• Standing & locomotion (stability/mobility)

Question 8

Stability/Mobility Factors

Answer 8

• Shape & arrangement of articulating surfaces
• Ligaments crossing joint
• Tone of surrounding muscles

Question 9

Bony Contacts

Answer 9

• Low stability
• Small area
• High force transmission
• Femoral condyle & tibial plateau

Question 10

Menisci

Answer 10

• Deepen & stabilize articulating surfaces
• Fibrocartilage absorbs shock
• Protects hyaline cartilage & bone

Question 11

Medial Collateral Ligament (MCL)

Answer 11

• Attached to medial meniscus
• No space between

Question 12

Lateral Collateral Ligament (LCL)

Answer 12

• Separated from lateral meniscus
• Connects femur to fibula

Question 13

Cruciate Ligament Characteristics

Answer 13

• Midline of joint
• Crossed
• Named based on tibial attachment

Question 14

Anterior Cruciate Ligament

Answer 14

• Attachment at anterior tibia
• Attachment at posterior femur
• Intracapsular
• Extrasynovial

Question 15

ACL Function

Answer 15

• Prevents femur from moving posteriorly on tibia (foot planted)
• Prevents tibia moving anteriorly under femur (free foot)

Question 16

Posterior Cruciate Ligament

Answer 16

• Attachment at posterior tibia
• Attachment at anterior femur

Question 17

PCL Function

Answer 17

• Prevents femur moving anteriorly on tibia (foot planted)
• Prevents tibia from moving posteriorly under femur (free foot)

Question 18

PCL Rupture

Answer 18

• Hyperextension of knee
• Blow to tibial tuberosity
• Moves tibia posteriorly on femur

Question 19

ACL Rupture

Answer 19

• Rotation of knee (foot medial & thigh lateral)
• Blow to lateral femur

Question 20

Unhappy Triad

Answer 20

• Tearing of MCL, ACL, medial meniscus

Question 21

Patellar Dislocation

Answer 21

• Laterally
• Pull on vastus lateralis
• Resisted by vastus medialis & high lateral femoral condyle

Question 22

Knee Movements

Answer 22

• Flexion/extension
• Minimal rotation

Question 23

Standing

Answer 23

• Knee joint locks
• Promote stability & efficiency

Question 24

Mechanisms of Standing

Answer 24

• Femur internally rotates
• Greater translation of medial femoral condyle

Question 25

Unlock Knee

Answer 25

• Femur rotates laterally

Question 26

Popliteus Muscle

Answer 26

• Triangular shaped
• Lateral aspect of femur
• Attaches to medial tibia

Question 27

Popliteus Muscle Function

Answer 27

• Unlocks knee
• Rotation of tibia & femur in opposite directions

Question 28

Popliteus Innervation

Answer 28

• Tibial nerve

Question 29

Patella

Answer 29

• Largest sesamoid bone
• Exists within tendon
• Extends moment arm of quads (further from joint line)
• Increased force produced when moving shank

Question 30

Muscle Groups Acting on Knee

Answer 30

• Anterior thigh
• Posterior thigh
• Medial thigh
• Shank
• Popliteus

Question 31

Shank Muscles

Answer 31

• Gastrocnemii
• Plantaris

Question 32

Knee Bursa

Answer 32

• Provide protection to tendon & skin crossing bony elements
• Fluid filled sacs
• Reduce friction

Question 33

Subpatellar Bursa

Answer 33

• Protect patella from femur

Question 34

Prepatellar Bursa

Answer 34

• Protect skin from anterior knee (knee bending)

Question 35

Infrapatellar Bursa

Answer 35

• Superficial and deep locations
• Protect patellar tendon