The thoracic spine refers to the upper- and middle-back. It joins the cervical spine and extends down about five inches past the bottom of the shoulder blades, where it connects with the lumbar spine. The thoracic spine is made up of twelve vertebrae, labeled T1-T12. While the cervical spine is built for flexibility (e.g. turning the head) and the lumbar spine is built for power and flexibility (e.g. lifting heavy objects, touching the toes), the thoracic spine is built for stability. This stability plays an important role in holding the body upright and providing protection for the vital organs in the chest.
UPPER Back Pain AND THE THORACIC SPINE
The thoracic spine is an intricate construct of bones, connective tissues, nerves, muscles, spinal segments, and joints. While the thoracic spine has a solid construction and is relatively stable, it can also be a source of pain.
- Muscular problems. Upper back pain is most commonly caused by muscle irritation or tension, also called myofascial pain. The cause may be poor posture or any type of irritation of the large back and shoulder muscles.
- Joint Dysfunction. Pain caused by joint dysfunction, where the ribs attach to the spine at each level of the thoracic spine, can cause pain.
- Herniated or degenerative discs. While less common in the thoracic spine, degenerative disc disease or a thoracic herniated disc can be a source of pain.
- Arthritis. Swelling due to arthritis in the spine can cause tenderness, pressure to the nerve, and limited range of motion. Often due to wear and tear of the aging process, the cartilage in the facet joints can become thin or disappear or can produce an overgrowth of bone spurs and an enlargement of the joints. Facet joint disorders of the thoracic spine can result from osteoarthritis.
- Vertebral fractures. Compression fractures due to osteoporosis are a main cause of thoracic spine pain in the elderly. While compression fractures can occur anywhere in the spine, they typically occur in the lower vertebrae of the thoracic spine (T9-T12).
- Kyphosis (hunchback). In addition to vertebral fractures, kyphosis can be caused by many factors, such as poor posture or a deformity, such as ankylosing spondylitis or Scheuermann's kyphosis. While kyphosis is primarily a deformity, it can also be a source of pain.
- Scoliosis. Scoliosis is a condition in which the spine abnormally curves sideways and can sometimes produce upper back pain.
Occasionally, pain felt in the thoracic spine can be a symptom of a more serious underlying disease or problem. Both musculoskeletal diseases and non-orthopedic conditions (such as a cancerous tumor exerting pressure on the spine) can cause upper back pain, as well as certain diseases of the heart, lungs, abdominal organs, or kidneys.