The spinal column, also known as the vertebral column or backbone, is a vital structure in the human body that provides support, protection, and flexibility. It is a complex assembly of bones, discs, nerves, and muscles. Below is a detailed description:

Structure of the Spine

The spine consists of 33 vertebrae, divided into five regions:

1. Cervical Spine (Neck Region)

• 7 vertebrae (C1–C7)

• Supports the head and allows for movement such as nodding and rotation.

• Notable vertebrae:

• C1 (Atlas): Supports the skull.

• C2 (Axis): Enables head rotation.

2. Thoracic Spine (Upper Back)

• 12 vertebrae (T1–T12)

• Attached to the ribs, forming the ribcage to protect organs like the heart and lungs.

3. Lumbar Spine (Lower Back)

• 5 vertebrae (L1–L5)

• Bears the weight of the upper body and provides flexibility and movement.

4. Sacral Spine (Pelvic Region)

• 5 fused vertebrae (S1–S5)

• Forms the back of the pelvis, providing stability and connecting the spine to the hips.

5. Coccyx (Tailbone)

• 4 fused vertebrae

• Acts as an attachment point for muscles and ligaments.

Intervertebral Discs

• Located between vertebrae, these cartilage structures act as shock absorbers and allow flexibility.

• They consist of:

• Nucleus Pulposus: The soft, gel-like core.

• Annulus Fibrosus: The tough outer layer.

Spinal Cord and Nerves

• The spinal cord runs through the spinal canal, protected by the vertebrae.

• It is part of the central nervous system, transmitting signals between the brain and the rest of the body.

Functions of the Spine

1. Support: Provides the framework for the body, supporting the head, shoulders, and torso.

2. Movement: Enables a wide range of motion, including bending, twisting, and stretching.

3. Protection: Safeguards the spinal cord and surrounding nerves.

4. Flexibility and Shock Absorption: Discs and curves in the spine absorb shocks during activities like walking and running.

Curves of the Spine

• The spine has natural curves that enhance its strength and balance:

• Cervical and Lumbar (Lordotic Curves): Inward curves.