Ligament And Joint Injuries

Question 1

What are ligaments composed of?

Answer 1

Collagen, elastin, proteoglycan, and other proteins

Question 2

Risks associated with ligament injuries

Answer 2

• Ligament scars (weaker tensile strength and viscoelastic properties)
• high risk of reinjury
• decreased proproception

Question 3

At what percentage of length increase will the collagen fibres begin to rupture?

Answer 3

4% (permanent microdamage)

Question 4

Example of intra-articular ligaments

Answer 4

Crucial ligaments of knee (inside capsule)

Question 5

Example of extra-articular ligaments

Answer 5

Calcaneofibular (outside joint capsule)

Question 6

Example of capsular ligaments

Answer 6

Anterior talofibular (thickens capsule)

Question 7

How do ligaments adapt to increased loading?

Answer 7

Slowly increase cross-sectional area

Question 8

What percentage can systematic training increase ligament strength

Answer 8

10-20%

Question 9

Passive subsystem

Answer 9

Non-contractile connective tissues

Question 10

Active subsystem

Answer 10

Controlled by neural subsystem to provide dynamic joint stability

Question 11

Valgus

Answer 11

Buckling inward (think “g” colliding)

Question 12

Virus

Answer 12

Outward, bow legs (think “r” for rarely touch)

Question 13

‘Felt my knee cap go out”

Answer 13

Patellar dislocation/subluxation

Question 14

Hit from lateral side (valgus)

Answer 14

MCL, ACL

Question 15

Valgus/external rotation (with or without contact)

Answer 15

ACL, MCL, lateral meniscus, bone bruise

Question 16

Direct blow to anterior tibia

Answer 16

PCL

Question 17

Hyperextension injury

Answer 17

ACL

Question 18

Minor twist in older individual

Answer 18

Degenerative meniscal tear

Question 19

Injuries that cause hemarthrosis (bleeding in the joint)

Answer 19

ACL tear, peripheral meniscus tear, osteochondral injuries, fractures

Question 20

Injuries that should not usually cause hemarthrosis

Answer 20

MCL tear, central meniscus tear, PCL tear, cartilage injury

Question 21

ACL bundles

Answer 21

1) anteromedial (resist anterior translation)
2) posterolateral bundle (resist rotation)

… no pain fibres, but proprioceptive

Question 22

When is MRI imaging necessary?

Answer 22

All dislocated knees, surgical planning, bone damage, multiple ligaments involved

Question 23

When is the ACL graft the weakest?

Answer 23

Right when you start to feel okay (3 to 6 months)

Question 24

Modifiable risk factors in the prevention of ACL injuries

Answer 24

• Weak hip abductors and external rotators
• increased knee abduction during cutting and landing

Question 25

Subluxation

Answer 25

Partial dislocation of articulating bones

Question 26

Dislocation

Answer 26

Complete separation of articulating bones

Question 27

Mechanisms for glenohumeral (shoulder) dislocation

Answer 27

• Direct blow to shoulder
• landing on outstretched arm

Question 28

Labrum injuries (slap tear)

Answer 28

Surrounds socket for stability and is a connection point long head of biceps tendon

Question 29

Are shoulder injuries at a high risk of recurrence?

Answer 29

Yes, 50 - 90 %