1
2
3
4
5
100

Bone that starts as mesenchymal tissue --> cartilage --> bone
- Axial skeleton
- Long bones 

Endochondral 

100

By what age will children have most of their secondary ossification centers that develop distal to the center of the bone? 

5 yo

100

At what age are the growth plates fused? 

25 yo

100

What is the transition to the end of the bone called? 

Metaphysis 

100

What is the growth plate itself called? 

Physis 

200

Osteoblasts are short bones or long bones? 

Short bones 

200

Bone that goes from mesenchymal tissue --> bone
- Flat bones
- Cranial bones
- Clavicle 

Intramembranous 

200

What is the end of the bone called? 

Epiphysis  

200

What is the middle portion of the bone called? 

Diaphysis 

200

Age range: 

Ossification of long bones is beginning 

3rd month of embryonic development 

300

- Begins 6-7th week of embryonic development
- Completes by age 25
- 2 types: intramembranous (cranial bones, clavicle) and endochondral (axial skeleton, long bones) 

Osteogenesis 

300

Do chondrocytes produce short or long bones? 

Long bones 

300

Age range:

Most primary ossification centers have formed in diaphysis 

4th month of embryonic development 

300

Age range: 

Ossification rapidly occurs as most long bones are developing 

5-12 yo in females, 5-14 in males 

300

Age range: 

Secondary ossification centers appear in epiphysis 

Birth-5 years ** 

400

Age range: 

Sternum, clavicle, vertebrae are becoming completely ossified 

23-25 yo 

400

Age range: 

UE bones are scapulae becoming completely ossified 

17-20 yo 

400

Age range: 

Full ossification has occurred 

25 yo *** 

400

Age range: 

LE bones and coccyx are becoming completely ossified 

18-23 yo 

400

High impact jumping activities with GRF of 3.5-8.8x body weight increases bone mass and mineral density
 - High school footballers > swimmers and cyclists
 - Gymnastics is one of the best osteogenic activities
Intensity of activity > duration
 - Best for osteogenesis was > 3.5x body weight and duration of 0.1 seconds
Moderate-vigorous activity most effective
 - Ages 11-13
 - > 15 mins 

Physical activity and osteogenesis 

500

What are the guidelines for moderate-vigorous exercise for children? 

% of youths that meet these guidelines? 

60 min/day 

25-30% 

500

- Leafy vegetables, lean protein (chicken/fish), low-fat dairy, whole grains, and nuts/seeds
- Breast feeding as infant
- Mother and patient diet of milk, phosphorus, magnesium, potassium, protein, folate, calcium and vitamin D 

Increased bone density and mass -- Diet and osteogenesis 

500

Only ___% of PE classes showed to meet threshold for moderate to vigorous physical activity? 

40% 

500

- High fat
- High inflammatory diet
   - High fat
   - High sodium
   - Processed foods 

Reduction in bone formation and density -- diet and osteogenesis 

500

The evidence suggests that incorporating muscle and bone strengthening activities at least 3 days per week is beneficial. What % of adults meet this recommendation? 

18%