Vertebral Column Anatomy and Bones [Cervical, Thoracic, Lumbar, Sacral Spine]

Recent questions

• What are the types of vertebrae?

  The human vertebral column is composed of 33 vertebrae, categorized into two main types: mobile and fused vertebrae. There are 24 mobile vertebrae, which include 7 cervical vertebrae in the neck region, 12 thoracic vertebrae in the upper back, and 5 lumbar vertebrae in the lower back. These mobile vertebrae allow for flexibility and movement. In addition, there are 9 fused vertebrae, which consist of 5 sacral vertebrae that form the sacrum and 4 coccygeal vertebrae that make up the coccyx or tailbone. The mobile vertebrae are positioned superiorly, while the fused vertebrae are located inferiorly in the spinal column, providing structural support and stability to the body.

• How do vertebrae support the body?

  Vertebrae play a crucial role in supporting the human body by providing a strong and flexible framework. The cervical vertebrae, which are the uppermost vertebrae, support the head, which weighs around 10 to 12 pounds. The thoracic vertebrae protect vital organs such as the heart and lungs while also anchoring the rib cage, which is essential for respiratory function. The lumbar vertebrae, being larger and more robust, are designed to bear the weight of the upper body and assist in lifting heavy objects. This structural arrangement allows for a balance between mobility and stability, enabling the spine to absorb shock and distribute loads effectively during various activities.

• What is a herniated disc?

  A herniated disc is a common spinal condition that occurs when the nucleus, or gel-filled center, of an intervertebral disc protrudes through the annulus, which is the fibrous outer layer of the disc. This protrusion can compress nearby spinal nerves, leading to pain, numbness, or weakness in the affected area. Herniated discs often occur in the lumbar region due to the significant weight-bearing demands placed on the lower back. Symptoms can vary depending on the location of the herniation and the nerves affected. Treatment options may include physical therapy, pain management, and in some cases, surgical intervention to relieve pressure on the nerves and restore normal function.

• What is the function of intervertebral discs?

  Intervertebral discs serve as crucial components of the vertebral column, providing cushioning and support between the individual vertebrae. Each disc consists of two main parts: the annulus, which is the tough, fibrous outer layer, and the nucleus, which is the soft, gel-filled center. These discs absorb shock during movement and help maintain the flexibility of the spine, allowing for a range of motions such as bending and twisting. They also play a role in distributing loads across the vertebrae, which is essential for preventing injury. Notably, there is no intervertebral disc between the first and second cervical vertebrae, which allows for a greater range of motion in the neck.

• What are the cervical vertebrae?

  The cervical vertebrae are the seven vertebrae located in the neck region, designated as C1 through C7. They play a vital role in supporting the head and facilitating its movement. The first cervical vertebra, known as the atlas (C1), supports the skull and allows for nodding motions, while the second cervical vertebra, called the axis (C2), enables rotational movement of the head. The cervical vertebrae are unique in that they feature transverse foramina, which are openings that allow for the passage of arteries and nerves. This anatomical structure is essential for maintaining blood flow to the brain and providing nerve function to the upper body. Overall, the cervical vertebrae are crucial for both structural support and mobility of the head and neck.