spinalsegmenten

Spinal segments are the distinct, repeating units that make up the vertebral column, or spine. Each segment comprises a vertebral body, a vertebral arch, and several processes. The vertebral body forms the weight-bearing anterior portion, while the vertebral arch encloses the spinal cord posteriorly. From the vertebral arch, various processes project, including spinous processes, transverse processes, and articular processes, which facilitate muscle attachment and articulation with adjacent vertebrae.

There are typically 33 vertebrae in the human spine, divided into five regions: cervical (7 vertebrae), thoracic (12 vertebrae), lumbar (5 vertebrae), sacral (5 fused vertebrae forming the sacrum), and coccygeal (4 fused vertebrae forming the coccyx). While the sacrum and coccyx are fused, the upper regions consist of individual, articulating vertebrae. The number and structure of spinal segments can vary slightly between individuals and species.

These segments are crucial for spinal mobility, stability, and protection of the central nervous system. Intervertebral discs, made of fibrocartilage, are located between the vertebral bodies, acting as shock absorbers and allowing for movement between segments. Spinal nerves exit the spinal cord through intervertebral foramina, which are formed by the articulation of adjacent vertebrae. Disorders affecting spinal segments can lead to pain, neurological deficits, and mobility issues.