Vertebral Column - Introduction | 3D Anatomy Tutorial

Recent questions

• What is the axial skeleton?

  The axial skeleton is a crucial part of the human body that includes the vertical column, which supports body weight and protects the spinal cord. It consists of 24 articulating vertebrae, categorized into 7 cervical, 12 thoracic, and 5 lumbar vertebrae, along with 9 fused vertebrae made up of 5 sacral and 3-4 coccygeal vertebrae. This structure not only provides stability and support but also plays a vital role in the overall function of the skeletal system, allowing for movement and flexibility while safeguarding the central nervous system.

• How do intervertebral discs function?

  Intervertebral discs serve as essential components of the spine, acting as shock absorbers between each vertebra. They are composed of two main parts: the outer fibrous ring known as the annulus fibrosis and the inner gelatinous center called the nucleus pulposus. This unique structure allows the discs to withstand pressure and provide cushioning during movement. However, if the annulus fibrosis tears, it can lead to disc herniation, which may compress the spinal cord or nerve roots, potentially causing pain and requiring medical attention to address the issue.

• What are spinal nerves?

  Spinal nerves are critical components of the nervous system that emerge from the spinal cord and are named based on their exit level from the vertical column. There are 31 pairs of spinal nerves, with 8 cervical spinal nerves corresponding to 7 cervical vertebrae. For instance, the first cervical spinal nerve exits above the first cervical vertebra (C1), while the L3 spinal nerve exits between the third and fourth lumbar vertebrae (L3 and L4). These nerves are responsible for transmitting sensory and motor information between the body and the central nervous system, playing a vital role in bodily functions and responses.

• What are the curvatures of the spine?

  The adult vertical column features four distinct curvatures that contribute to its overall structure and function. These include cervical lordosis, which is an anteriorly convex curve in the neck region; thoracic kyphosis, a dorsally convex curve in the upper back; lumbar lordosis, another anteriorly convex curve in the lower back; and pelvic curvature, which is concave anteriorly. These curvatures are essential for maintaining balance and posture, as well as allowing for various movements such as flexion, extension, rotation, and lateral flexion, all of which are influenced by the morphology of the vertebral joints and the surrounding ligamentous structures.

• What causes disc herniation?

  Disc herniation occurs when there is a tear in the outer fibrous ring of an intervertebral disc, known as the annulus fibrosis, allowing the inner gelatinous center, or nucleus pulposus, to protrude out of its normal position. This condition can exert pressure on the spinal cord or nearby nerve roots, leading to pain, numbness, or weakness in the affected areas. Factors contributing to disc herniation include age-related degeneration, excessive strain or injury, and improper lifting techniques. Understanding the mechanics of the spine and the role of intervertebral discs is crucial for preventing and managing this common spinal issue.