Vertebral Column Notes

Functions: Protect spinal cord, support head, attachment site for muscles (back, upper limb, pelvic girdle, ribs).
Flexible rod, strong, allows movement and rotation.

Total: $26$ vertebrae (adult).
Breakdown: $7$ cervical, $12$ thoracic, $5$ lumbar, $1$ sacrum, $1$ coccyx.
- Mnemonic: $7, 12, 5$ (breakfast, lunch, dinner).

Adult: $4$ curves (cervical, thoracic, lumbar, sacral).
Infant (Born with): $2$ curves (thoracic, sacral) - primary curves.
Secondary Curves: Develop after birth.
- Cervical curve (when baby holds head up).
- Lumbar curve (when able to stand/walk).
Functions of curves: Balance, upright posture, increased column strength.

Located between bony vertebrae.
Composition: Outer rim of fibrocartilage (annulus fibrosus), inner pulpy substance (nucleus pulposus).
Functions: Form joints, allow flexibility, cushion, contribute to height.
Herniated/Slipped Disc: Rupture/protrusion of nucleus pulposus, pressing on spinal nerves.
- Symptoms: Pain, tingling, numbness.
- Most common in lumbar region due to bearing most body weight and frequent flexing/bending.
- Treatment: Physical therapy (minor), surgery (severe).

Body: Thick, weight-bearing part.
Vertebral Foramen: Hole for spinal cord.
Vertebral Arch: Formed by lamina and pedicles.
Intervertebral Foramen: Openings for spinal nerves.
Processes:
- Spinous process: $1$ , projects posteriorly, palpable along back.
- Transverse processes: $2$ , project laterally.
- Facets: $2$ superior and $2$ inferior, covered with hyaline cartilage, articulate with adjacent vertebrae.

Cervical Vertebrae (C1-C7):
- Smallest (except coccyx).
- Characteristic: $3$ holes (vertebral foramen and $2$ transverse foramina).
- Some have bifid (split) spinous processes (e.g., C3-C6).
- Atlas (C1): No body, no spinous process. Grooves for occipital condyles; allows