How does my spine fit together?

• The spine is also known as the backbone and it is present in the central portion of the human body on the backside.
• The human spine consists of small multiple bones joined together by ligaments in a particular alignment.
• The spine is a very complex structure that has multiple functions in the human body.

The human spine consists of –

Vertebrae

There is a total of 33 vertebrae present in the human body. Those vertebrae are divided into five sections. Cervical, Thoracic, Lumbar, Sacral and coccyx.

Cervical (Total 7)

1. It is the topmost part of the vertebrae present in the neck.
2. They range from C1 toC7 (C=Cervical).
3. This vertebra allows us to tilt our head in different directions.

Thoracic (Total 12)

1. It is the second part of the vertebral column situated just below the cervical spine.
2. They range from T1 to T12 (T=Thoracic).
3. Their prime work is to hold ribs for the making of the thoracic cage which protects the lungs and heart.
4. They are less flexible as compared to the cervical spine.

Lumbar (Total 5)

1. It is the next part of the Vertebral column.
2. They range from L1 to L5 (L=Lumbar).
3. They bear the responsibility of lifting body weight.
4. They also help in the stress lifting of objects.
5. Along with weight-bearing, they also support the upper two parts of the spine.

Sacrum (Total 5)

1. They are triangular in shape.
2. They range from S1 to S5 (S=Sacrum).
3. These five bones are fused together and do not move in any direction.
4. Their main function is to the joint the spine to the hip joint.
5. Pelvic Girdle is the ring-like bony structure formed by Sacrum and hip joints.

Coccyx (Total 4)

1. It is the last part of the vertebral column.
2. The coccyx is also called the tailbone.
3. It is made up of four fused coccygeal vertebrae.
4. Its main function is to provide a surface attachment for ligaments and muscles.

Intervertebral Disc

• The space between the two vertebrae is filled up by a soft cushion-like structure called an intervertebral disc.
• They serve as a shock absorber for those two vertebrae.
• They also prevent the rubbing of two vertebral surfaces in the spine.
• They also provide protection for the nerves running within them.

Facet Joints

• They allow back movement in the human spine.
• All vertebra has four facet joints – two above and two below.
• The above portion of the facet joint is attached to the vertebrae above and below ones are attached to the next vertebrae.
• They allow the easy sliding of one vertebra to the next and provide flexibility and stability.
• They allow the spine to be perfectly aligned with each other.

Spinal Cord and Nerves

• The spinal cord starts from the brain stem and extends to the first lumbar vertebrae.
• The passing of messages from different body parts to the brain and vice versa is done by the spinal cord and nerves

Ligaments

• Ligaments are a band of strong fibrous connective tissue.
• They are covered around the vertebral column
• The presence of ligaments in the vertebral column minimizes the extra movement of vertebrae.
• It also protects the disc and stabilizes the spine.

Fun Facts:

1. Our Spinal cord is about 18 inches long and the width of our finger.
2. The spine has about 120 muscles in it.
3. The total weight of the spinal cord is about 35 grams.

Additional Questions:

1. What are the parts of the vertebrae?
2. How many pairs of the spinal cord are present in the human body?
3. What are the key points for differentiation of thoracic and lumbar vertebrae?

True or False:

1. There are 33 pairs of vertebrae present in the human body.
2. The uppermost part of the vertebral column is the thoracic vertebrae.
3. The cervical spine is a fused spine.
4. The thoracic spine allows a limited range of motion.
5. The spinal cord starts from the brain stem till the first lumbar vertebrae.

Objective Quiz:

1. There are _________ total vertebrae in human body.
   1. 33
   2. 14
   3. 40
   4. 34
2. Vertebrae are divided in ________ sections.
   1. 4.
   2. 5.
   3. 3.
   4. 6.
3. Spinal cord passes through the ________.
   1. Spinal canal.
   2. Brain canal.
   3. Lumbar canal.
   4. All of the above.
4. Intervertebral disc are present between _________.
   1. Two vertebrae.
   2. Five vertebrae.
   3. One vertebra.
   4. They are coated on the whole vertebral column.
5. There is _______ number of facets present in each vertebra.
   1. 4.
   2. 2.
   3. 6.
   4. 8.