Age related changes in bone occur before birth till death. The changes from utero to childhood to maturity and till adults are presented here.
Age related changes in bone is a must know topic for all orthopedic surgeons. It is equally important to all residents for gaining knowledge and passing exams as well.
We present here the order of bone changes from embryonic to adult life through the stages of childhood and adolescence.

18 age related changes in bone
Embyronic: Pass through the stages of condensation — > chondrification — > ossification in order
- Embryonic development begins with appearance of arm buds 4 weeks from fertilization and leg buds shortly afterwards
- 5 weeks – finger and toe ray differentiate
- 6 weeks – vascularized and primary ossification center appear
- 7-8 weeks: joints start appearing, cartilaginous epiphyseal precursor become vascularized
- 8-12 weeks: primitive joints and synovium defined
- Till birth: Bone formation continues along diaphysis and epiphyseal ends remain unossified until after birth
After birth
7. Soon after birth – secondary ossification center begins to appear
Childhood
8. Endochondral ossification continues till adolescence via growth in epiphysis, physis and diaphysis
Adolescence
9. Longitudinal growth continues until the epiphysis fuses with the diaphysis
10. Periosteal bone formation / appositional ossification also occurs
11. Physis closes (usually 14 years for girls and 16 years for boys) ending bone growth.
Adults
12. Bone do not grow, but remodeling continues throughout the life
13. Peak bone mass is the amount of bony tissue present at the end of the skeletal maturation. Occurs between 16 and 25 years of age. After this period, bone loss starts. However, remodeling continues till death.
You may also like
External Links