Nivelsäikeet

Nivelsäikeet, also known as ligamenta flava, are a specific type of elastic ligament found in the vertebral column. They connect the laminae of adjacent vertebrae, forming a portion of the posterior wall of the vertebral canal. These ligaments are predominantly composed of elastic fibers, which give them their name and characteristic yellowish color. This elasticity is crucial for their function.

The primary role of the ligamenta flava is to help maintain the posture of the vertebral column and assist in extending it back to the anatomical position after flexion. Their elastic nature allows them to passively recoil, pulling the vertebral arches back and narrowing the vertebral canal during extension. This recoil also plays a significant role in preventing excessive flexion of the spine, thereby protecting the spinal cord and intervertebral discs from injury.

During spinal flexion, the ligamenta flava are stretched. As the spine moves back towards extension, these ligaments contract, providing an elastic pull that aids in the return to an upright posture. This constant interplay between stretching and recoil contributes to the dynamic stability of the spine. They also help to seal the vertebral canal, preventing the dura mater from being impinged during spinal movements. Pathological changes or ossification of the ligamenta flava can lead to spinal stenosis, a condition where the vertebral canal narrows, potentially compressing the spinal cord or nerve roots.