Though you might think of your spinal cord as one single piece, it's actually a column of nerves protected by a sheath of myelin and then further secured by 31 butterfly-shaped vertebrae (singular: vertebra).
Medical providers divide the spinal cord into four distinct regions. Knowing the region in which the injury is located is often the key to understanding diagnosis and treatment. The four spinal cord regions are:
The cervical spinal cord: This is the topmost portion of the spinal cord, where the brain connects to the spinal cord, and the neck connects to the back. This region consists of eight vertebrae, commonly referred to as C1-C8. All spinal cord numbers are descending, so C1 is the highest vertebra, while C8 is the lowest in this region.
The thoracic spinal cord: This section forms the middle of the spinal cord, containing twelve vertebrae numbered T1-T12.