Hard Tissue (Bone), Cartilage, Tendons/Ligaments, Nerves/Joints

Question 1

What makes up bone tissue?

Answer 1

Collagen, ground substance, and minerals

Question 2

Is bone tissue vascular?

Answer 2

Highly vascular

Question 3

Why is it important for bone to be highly vascular?

Answer 3

Excellent capacity for self-repair

Question 4

What kind of bone is tougher: cortical or trabecular?

Answer 4

Trabecular

Question 5

What is the term referring to how bone tissue exhibits distinct mechanical properties when loaded along various axes because its structure differs in the transverse and longitudinal directions?

Answer 5

Anisotropic

Question 6

Which can cortical bone tolerate more: longitudinal loads or transverse loads?

Answer 6

Longitudinal loads

Question 7

What are the two general ways in which a bone fracture can occur?

Answer 7

Single load that exceeds the ultimate strength of the bone OR repeated applications of lower-magnitude loads

Question 8

What type of stress is cortical bone BEST at withstanding: tension, shear, or compression?

Answer 8

Compression

Question 9

What type of stress is cortical bone the WORST at withstanding: tension, shear, or compression?

Answer 9

Shear

Question 10

What is the concept referring to how bone has the ability to remodel by altering its size, shape, and structure to meet the mechanical demands placed on it?

Answer 10

Wolff’s Law

Question 11

What happens to bone that is not needed for reasons such as disuse or aging?

Answer 11

Resorbed

Question 12

Is cartilage vascular?

Answer 12

No (semi-exception = articular cartilage with minimal blood supply)

Question 13

What makes up cartilage?

Answer 13

Collagen, chondrocytes, and ground substance

Question 14

What are the three types of cartilage?

Answer 14

Articular, hyaline, and fibrocartilage

Question 15

What are the three main functions of cartilage?

Answer 15

Increase joint stability
Shock absorption
Protection of bone

Question 16

What property of articular cartilage makes it more susceptible to creep and relaxation?

Answer 16

It is viscoelastic

Question 17

What is the range of the forces present at the joint surface during joint articulation?

Answer 17

0-10X body weight

Question 18

What allows cartilage to experience minimal wear under varied load?

Answer 18

Synovial lubrication

Question 19

For what reason is cartilage considered to be unlike any man-made material?

Answer 19

Near frictionless properties

Question 20

What is interfacial wear of articular cartilage?

Answer 20

Interaction of bearing surfaces

Question 21

What causes interfacial wear of articular cartilage?

Answer 21

Adhesion or abrasion

Question 22

What is fatigue wear of articular cartilage?

Answer 22

Bearing deformation under load

Question 23

What causes fatigue wear of articular cartilage?

Answer 23

Repetition of high loads over short period OR repetition of low loads of extended period

Question 24

Why does articular cartilage have a limited capacity for repair and regeneration?

Answer 24

Small blood supply

Question 25

What two things determine the magnitude of the stress sustained by articular cartilage?

Answer 25

Total load on the joint AND how the load is distributed over the articular surface contact area

Question 26

What is the term for the fibrous tissue that connects muscle to bone?

Answer 26

Tendon

Question 27

What is the term for the fibrous tissue that connects bone to bone?

Answer 27

Ligament

Question 28

What makes up tendons and ligaments?

Answer 28

Collagen and fibrocytes

Question 29

What is the location where tendons join to skeletal muscle?

Answer 29

Musculotendinous junction

Question 30

What are the three characteristics stages for the healing of strains and sprains?

Answer 30

``` 1 Inflammation (Up to 72 hours) 2 Repair (28 hours to up to 6 weeks) 3 Remodeling (3 weeks to 12 months) ```

Question 31

In what stage of sprain/strain healing do we see the collagen changing to increase function?

Answer 31

Remodeling stage

Question 32

What is the definition of a strain?

Answer 32

Overexertion of stress on CONTRACTILE tissues

Question 33

What kinds of muscles are most at risk for a strain?

Answer 33

Fusiform muscles crossing 2 joints (examples = hamstrings, rectus femoris, biceps brachii)

Question 34

Are muscle strains more common in the upper or lower extremity?

Answer 34

Lower

Question 35

In what grade of a strain or sprain are only a few fibers torn (less than 1/4) with only minor weakness and no palpable defect?

Answer 35

Grade One

Question 36

In what kind of strain or sprain is about 1/4-1/2 of the muscle/tendon torn with moderate to major weakness and loss of function?

Answer 36

Grade Two

Question 37

In what kind of strain or sprain are all fibers torn with minor to no pain and possible increased range of motion?

Answer 37

Grade Three

Question 38

What is the term for overexertion or stress on NON-CONTRACTILE tissues?

Answer 38

Sprain

Question 39

What two things can be sprained?

Answer 39

Ligament or capsule

Question 40

What two types of damage to nerves can produce mechanical deformation on them?

Answer 40

Trauma or nerve entrapment

Question 41

What are the two most common modes of nerve injury?

Answer 41

Stretching (tensile forces) and compression

Question 42

What is the maximal elongation elastic limit of nerves?

Answer 42

About 20%

Question 43

At what percentage of elastic limit does complete structural failure occur to a nerve?

Answer 43

Approximately 25% to 30%

Question 44

What comes first: severe intraneural tissue damage of a nerve or nerve failure/rupture?

Answer 44

Severe tissue damage (long before)

Question 45

What is usually the cause for tensile nerve injuries?

Answer 45

Result of accidents

Question 46

What symptoms can result from nerve compression?

Answer 46

Numbness, pain, muscle weakness

Question 47

At what level of local nerve compression can we see functional changes?

Answer 47

30 mmHg

Question 48

At what level of local nerve compression can we see complete cessation of intraneural blood flow and complete ischemia?

Answer 48

80 mmHg

Question 49

Can blood flow to neural tissue be restored even after over two hours of compression?

Answer 49

Yes

Question 50

What is the term for the resting position of a joint when it has the most slack?

Answer 50

Loose pack position

Question 51

What is the term for the position of a join when its surfaces are in the closest approximation and the capsule and ligaments are maximally stressed?

Answer 51

Close pack position

Question 52

What is the clinical term for when a joint becomes excessively restricted due to adhesions in the capsule?

Answer 52

Adhesive capsulitis

Question 53

What is unique about the limitation of range of motion in a joint?

Answer 53

Always found to be in a specific pattern

Question 54

What kinds of abnormalities can cause non-capsular patterns of joints?

Answer 54

Joint mice Impingements Plica Other internal derangements