The spine provides both support and flexibility. It protects the spinal cord and allows upright posture, bending, twisting, and shock absorption.
Regions
- Cervical (7 vertebrae)
- Thoracic (12)
- Lumbar (5)
- Sacrum
- Coccyx
Structural Components
- Vertebral bodies
- Intervertebral discs
- Facet joints
- Ligaments
Intervertebral Discs
Act as shock absorbers with:
- Annulus fibrosus (outer ring)
- Nucleus pulposus (inner gel)
Ligaments
- Anterior longitudinal
- Posterior longitudinal
- Ligamentum flavum
- Interspinous
Movements
- Flexion
- Extension
- Lateral flexion
- Rotation
Different regions emphasize different motions:
- Cervical: high mobility
- Thoracic: rotation
- Lumbar: flexion/extension
Stability System
Core muscles support spinal health:
- Transversus abdominis
- Multifidus
- Diaphragm
- Pelvic floor
Functional Considerations
Poor posture, prolonged sitting, or weak stabilizers often lead to disc degeneration, herniation, or chronic back pain.
Movement Insight
Length before depth. Balanced mobility and stability protect the spine.