Musculoskeletal Changes Across the Lifespan

Question 1

Cartilage types

Answer 1

• Hylaine/Articular Cartilage
  
  • fetal skeleton, joints, trachea, larynx
• Fibrocartilage
  
  • Meniscus, pubic symphysis, intevertebral discs.
• Elastic Cartilage:
  
  • ​Ear & epiglotis

Question 2

Types of cartilage growth:

Answer 2

• Appositional: New surface
• Interstitial: Increased internal mass
• Limited growth/repair after childhood

Question 3

Cartilage properties:
nutrients from?

Answer 3

• Lack of innervation, vascularization
  
  • Nutrients from diffusion
  • Compression/Decompression

Question 4

Cartilage: Over Time

Answer 4

• Thinning
• Atrophy
• Decreased water content
• Decreased number of Chondrocytes
• Rougher surface → decreased efficiency

Question 5

Bone is formed by endochondral ossification except:

Answer 5

Clavicle, carpals and tarsals, mandible, skull

Question 6

Diaphysis is ossified at

Answer 6

birth

Question 7

Bony maturity by

Answer 7

20 y

Question 8

Epiphyseal plate forms in

Answer 8

early childhood

Question 9

Interstitial bone growth:

Answer 9

• Growth in lenght (occurs befor growth in diameter)
• Compression forces (ideally symmetrical, perpendicular)

Question 10

Appositional bone growth:

Answer 10

• Growth in diameter
• Most rapid during prenatal period

Question 11

Joints form at _____ weeks gestation

Answer 11

6-8

• Change in response to loading and movement
• Acetabulum shows significant changes

Question 12

Femoral anteversion ________(decreases or increases?) over time

Answer 12

decreases

new born is 25 -30 deg

adult 10 -15 deg

Question 13

knee aligment development

Answer 13

• new born: peak varum
• 1-2 yr: straight
• 2-4 yr: peak valgum
• 16 yr: straight

Question 14

Bone in infancy and childhood:

Answer 14

• Growth is dynamic at this point
• Spontaneous resolution
• Relatively rapid response to ortho intervention
• Epiphysis vulnerable:
  
  • Infection or fracture
  • Asymmetrical growth

Question 15

Growing pains

Answer 15

• 4-12 year olds
• Late evening or night, resolve by am
• Muscle grows slower than bone

Question 16

Growth spurts at what age?

Answer 16

• 12-13 y for girls
• 14-16 for boys
• Decreased flexibility
• Length grows faster than cortical strength

Question 17

The role of hormones testosterone and strogen in bone growth

Answer 17

• Estrogen: Slows bone resorption (inhibits osteclasts activity)
• Testosterone: Enhances calcium absorption (increases osteoblast activity)

Question 18

Bone: Activity Related Concerns

Answer 18

Question 19

Salter-Harris fractures

Answer 19

Epiphyseal Injury

Question 20

Answer 20

Greenstick Fracture

in children

Question 21

Adolescent Bone Concerns:

Answer 21

• Scoliosis
• Apophysitis
• Apophyseal avulsion
• Stress fracture

Question 22

Cobb angle

Answer 22

• Named for convex side
• curve in scoliosis measurement
• Structural vs. Non structural
• 0-20: Monitor
• 20-40: Bracing & Exercise
• 40: Surgical stabilization

Question 23

Risser sign

Answer 23

• Bone Maturity measurement
• 0 to 5 scale
• 5 is completely closed

Question 24

Growth plates begin closing in ______ . And are complete by ____.

Answer 24

• childhood
• Complete by 25 years
• Vertebra close last
• Remodeling continues

Question 25

Annulus Fibrosis: Increasingly fibrotic Peak lost:

Answer 25

20-40y

Question 26

Adult Bone Concerns:

Answer 26

* Back pain/Disc changes * Nucleus Pulposus: Loss of volume * Annulus Fibrosis: Increasingly fibrotic

Question 27

Pre-natal and 1st year: \_\_\_\_\_(increases or decreases) **number of fibers**

Answer 27

**Increased**

Question 28

After 1st year: Increased fiber \_\_\_\_\_\_\_

Answer 28

size

Question 29

muscle maturation is achieved when

Answer 29

* Relaxation speed improves * Adult speeds reached by 10

Question 30

Bone growth is faster or slower than muscle?

Answer 30

faster

Question 31

Boys have a longer ___________ and sharper acceleration in growth

Answer 31

“growing period”

Question 32

Strength training can decrease speed of loss but not \_\_\_\_\_\_

Answer 32

prevent it

Question 33

**Sarcopenia:**

Answer 33

* Muscle wasting: decline in number and size of muscle fibers * Not typical! * Reported by 6-15% of older adults ∗ Activity level ∗ Hormonal level ∗ Loss of contractile properties

Question 34

Strength over the Lifespan: **adults**

Answer 34

* Continued increase into 20s * Peaks in the 30s * Declines into the 50s * Strength training can decrease speed of loss but not prevent * Frailty and advanced age **are not** contraindications for strengh training.

Question 35

cobb angle of 18 deg

Answer 35

just monitor

Question 36

cobb angle of 25 deg

Answer 36

bracing and exercise

Question 37

cobb angle of of 45 deg

Answer 37

surgical stabilization

Question 38

Pt presents with a cobb angle of 22 deg and you decide to: ## Footnote a. continue to monitor the curve b. recommend bracing and therapeutic exercises c. refer to a doctor for surgery

Answer 38

bet 20 -40 deg = bracing and exercise

Question 39

a 3 y/o has ## Footnote a. straigh legs b. peak valgum c. varum

Answer 39

peak valgum