- 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 –
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)
- It is the topmost part of the vertebrae present in the neck.
- They range from C1 toC7 (C=Cervical).
- This vertebra allows us to tilt our head in different directions.
Thoracic (Total 12)
- It is the second part of the vertebral column situated just below the cervical spine.
- They range from T1 to T12 (T=Thoracic).
- Their prime work is to hold ribs for the making of the thoracic cage which protects the lungs and heart.
- They are less flexible as compared to the cervical spine.
Lumbar (Total 5)
- It is the next part of the Vertebral column.
- They range from L1 to L5 (L=Lumbar).
- They bear the responsibility of lifting body weight.
- They also help in the stress lifting of objects.
- Along with weight-bearing, they also support the upper two parts of the spine.
Sacrum (Total 5)
- They are triangular in shape.
- They range from S1 to S5 (S=Sacrum).
- These five bones are fused together and do not move in any direction.
- Their main function is to the joint the spine to the hip joint.
- Pelvic Girdle is the ring-like bony structure formed by Sacrum and hip joints.
Coccyx (Total 4)
- It is the last part of the vertebral column.
- The coccyx is also called the tailbone.
- It is made up of four fused coccygeal vertebrae.
- Its main function is to provide a surface attachment for ligaments and muscles.
- 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.
- 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 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.
- Our Spinal cord is about 18 inches long and the width of our finger.
- The spine has about 120 muscles in it.
- The total weight of the spinal cord is about 35 grams.
- What are the parts of the vertebrae?
- How many pairs of the spinal cord are present in the human body?
- What are the key points for differentiation of thoracic and lumbar vertebrae?
True or False:
- There are 33 pairs of vertebrae present in the human body.
- The uppermost part of the vertebral column is the thoracic vertebrae.
- The cervical spine is a fused spine.
- The thoracic spine allows a limited range of motion.
- The spinal cord starts from the brain stem till the first lumbar vertebrae.
- There are _________ total vertebrae in human body.
- Vertebrae are divided in ________ sections.
- Spinal cord passes through the ________.
- Spinal canal.
- Brain canal.
- Lumbar canal.
- All of the above.
- Intervertebral disc are present between _________.
- Two vertebrae.
- Five vertebrae.
- One vertebra.
- They are coated on the whole vertebral column.
- There is _______ number of facets present in each vertebra.