The thoracolumbar spine describes the area containing both the thoracic and lumbar vertebrae of the spine, states Radiology Master Class. It is typically referred to in the case of a spinal injury.
Thoracic spine, also know as T-spine, pertains to the upper back and abdomen area, and is one of three major sections of the spinal column, states Healthline. It is found between the cervical spine in the neck and the lumbar spine within the lower back. The muscles that most affect the thoracic spine include the longissimus and spinalis. The longissimus is a long muscle that is found along the middle of the lumbar spine on each side of the spinalis, while the spinalis is made up of muscle ligaments that are attached to several thoracic vertebrae.
The lumbar spine, also known as the L-spine, refers to the lower back and is the bottom-most section of the spine, explains Healthline. This area of the spine is made up by the lumbar vertebrae, the sacrum and the coccyx. The lumbar vertebrae include the L1 through L5 vertebrae of the spinal column. Beneath it is the sacrum, which is a triangular-shaped vertebrae that is located behind the back of the pelvis. The coccyx is the small bone that is also popularly called the tailbone.