Middle back pain is defined as any type of pain or discomfort in the area between the upper and lower back. Health professionals refer to the middle back as lower thoracic or thoracic spine. Upper thoracic spine makes up the upper back area while the lumbar spine makes up the lower back.
The mid back area consists of nerves, spinal cord, spinal column, blood vessels, tendons and ligaments, and these structures can become irritated or inflamed in response to different mild to serious conditions. The discomfort may last briefly or may be chronic, lasting more than three months.