Vertebrae: Diagram, Classification, and Features

The bones of the vertebral column, also called the spine or backbone, support our body and protect the spinal cord. Each human vertebrae diagram typically shows 33 vertebrae in a developing spine, which later fuse into 26 distinct bones in most adults.

The vertebrae are divided into five major regions:

1. Cervical Vertebrae (C1–C7)

• Located at the top of the spine, just below the skull.

• Each cervical vertebrae has a vertebral foramen, where the spinal cord and blood vessels pass through.

• The first cervical vertebra (atlas, C1) and the second (axis, C2) allow head movement.

• Spinous process of C7 (called vertebra prominens) can be felt at the base of the neck.

2. Thoracic Vertebrae (T1–T12)

• Found in the mid-back region, connecting to the ribs.

• Characterised by transverse processes with costal facets that articulate with the ribs.

• The vertebral body is generally heart-shaped and broader than in the cervical region.

3. Lumbar Vertebrae (L1–L5)

• Located in the lower back, bearing much of the body’s weight.

• Each lumbar vertebrae has a large, kidney-shaped body for support.

• The spinous process here is broad and strong.

4. Sacral Vertebrae (S1–S5)

• These five segments fuse into one triangular bone called the sacrum.

• Forms part of the pelvis and connects with the hip bones on either side.

• Often fused between the ages of 18 and 30.

5. Coccygeal Vertebrae (Co1–Co4/5)

• Commonly known as the coccyx or tailbone, formed by three to five fused vertebrae.

• It has minimal movement but serves as an attachment site for ligaments and tendons.

Well-Labelled Diagram of all the Vertebrae in a Vertebral Column

Anatomy of a Typical Vertebra

A standard vertebra includes the following parts:

• Vertebral Body: A thick, cylindrical region in front that supports weight.

• Vertebral Arch: Composed of pedicles and laminae, forming a protective ring behind the vertebral body.

• Spinous Process: A bony projection at the back for muscle and ligament attachment.

• Transverse Processes: Two lateral projections used for muscle attachments and rib articulation (especially in thoracic vertebrae).

• Articular Processes: Joints that connect one vertebra to another, allowing controlled movement.

Quick Quiz (With Answers)

1. Which vertebra is known as the atlas?
A. C1
B. C2
C. T1
Answer: A (C1 is called the atlas.)

2. Which region of the spine bears most of the body’s weight?
A. Cervical
B. Lumbar
C. Thoracic
Answer: B (The lumbar region supports a large portion of our body weight.)

3. Which vertebrae form the tailbone?
A. Cervical
B. Thoracic
C. Coccygeal
Answer: C (The coccygeal vertebrae fuse to form the tailbone or coccyx.)

Importance of Maintaining a Healthy Spine

• Posture Support: Proper alignment of the bones of the vertebral column helps prevent back pain.

• Protecting the Spinal Cord: The foramen in each vertebra safeguards the spinal cord from injury.

• Movement and Flexibility: Joints between vertebrae allow bending and twisting in various directions.

• Shock Absorption: Intervertebral discs act like cushions, reducing the impact on the spine during activities.

Also Read: 

• Human Skeleton System

• Bones Anatomy

Conclusion

By understanding the human vertebrae diagram and each region’s features, you can appreciate how the spine maintains balance, flexibility, and protection for the spinal cord. A healthy spine is key to performing everyday activities with ease. If you have concerns about back pain or spinal alignment, it is always a good idea to consult a healthcare professional.