ossification (primary/secondary)

Introduction

The formation of bone or a change into bone. Typical vertebrae begin to ossify toward the end of the embryonic period (8th week) & ossification continues throughout the fetal period.

3 primary centers of ossification:

• one in the centrum
• one in each half of the vertebral arch

5 secondary centers of ossification (develop during puberty):-

• one at the tip of the spinous process
• one at the tip of each transverse process

All secondary ossification centers usually unite with the vertebra by the 25th year; however the times of the union are variable.

[Latin: ossification, from os = bone; facio = to make]

More general terms

• physiology

Additional terms

• bone turnover; bone repair; bone remodeling
• ectopic/dystrophic calcification
• incomplete ossification
• lack of ossification