Anatomy & Background
The thoracic spine, or mid back, is the largest section of the back and includes 12 vertebrae, with an intervertebral disc in-between each. The vertebrae are the bony building blocks of the back and spine. They are designed to protect the spinal cord, provide support and structure to the spine, and carry the weight of the head, neck and trunk. The vertebrae of each section of the spine are slightly different and specific to the function of that area.
Spinal and Facet Joints
All thoracic vertebral levels consist of three joints. There is one joint consisting of the intervertebral discs which connect the bodies of the vertebra. There are also two posterior and lateral joints with one on each side called facet joints. The facet joints provide support, stability and facilitate motion of the thoracic spine.
Facet joints are synovial joints, which have a smooth shiny contact surfaces called articular cartilage. The articular cartilage allows the bones to slide freely over each other with reduced friction and stress. Each joint is also surrounded by a protective sleeve called a capsule, and is lubricated by synovial fluid. The facet joints can become irritated and inflamed producing pain and dysfunction.
Each thoracic vertebra has a pair of ribs, one on each side. The twelve ribs form the thoracic cage and serve to protect the vital organs of the body (lungs, heart, liver, kidneys etc.) The nerves of the thoracic spine provide sensory and muscle innervations to the trunk and part of each arm. Additionally, the internal organs of the body supply these nerves.
The thoracic spine has less movement than the cervical and lumbar spine. The greatest amount of movement is forward bending or flexion. The ribs limit side bending and rotational, or turning, motions of the mid back.
Degenerative joint disease
Arthritis is a non-infectious, progressive disorder of the joints. The normal articular joint cartilage is smooth, white, and translucent. In early arthritis or joint degeneration, the cartilage becomes yellow and opaque with localized areas of softening and roughening of the surfaces. As degeneration progresses, the soft areas become cracked and worn, exposing bone under the cartilage. Eventually, osteophytes (spurs of new bone) covered by cartilage form at the edge of the joint. As mechanical wear increases, the cartilage cells are unable to repair themselves.
Degenerative joint disease is a common cause of back pain. The spinal facet joints, like other synovial joints of the body, are susceptible to wear-and-tear, degeneration, inflammation and arthritic changes. Inflammation and degenerative changes to the facet joints may result in pain, loss of motion, and severe encroachment or pinching of the nerve exiting the spinal column. Common causes of facet joint irritation include the following:
- Degeneration, arthritic changes, or general wear-and-tear of the joint over time.
- Disc degeneration may cause a loss of height between the vertebra placing a greater compression force on the posterior facet joints, increasing and accelerating wear-and-tear on these joints.
- Backward motions can produce compression on the facet joints, which can lead to degenerative, and eventual arthritic changes.
- A sudden fall or trauma, like a motor vehicle accident, can result in a facet joint irritation, increasing and accelerating wear-and-tear on joints.
- Ligament damage causing instability at the joint level and a subsequent increase in wear and stress on the spinal joints.
- Genetic factors can contribute to the likelihood of degenerative joint disease.
- Repetitive stress injuries like lifting or carrying heavy loads can cause facet joint irritation and degenerative joint disease.
- Chronic long term scoliosis or curvature of the spine can result in increased wear on the spinal facet joints.
The symptoms of degenerative joint disease will depend on the location of the joint and what structures are affected. Symptoms can vary from mild to severe and may mimic the symptoms of a disc problem:
- Pain in the back or radicular symptoms to the trunk or rib cage.
- Pain and tenderness localized at the level of the involved facet joint.
- Muscle spasms and changes in posture in response to the injury.
- Loss of motion, like the inability to bend backward, move sideways to the effected side, or stand erect, in addition to poor tolerance for sitting.
- Standing and walking can be difficult if the irritation is severe.
- Stiffness in the joints after a period of rest.
- Pain with excess activity and relief with rest.
- Localized swelling at the joint level may be present.
Treating Degenerative Joint Disease
Treatment of degenerative joint disease or injury will depend on the severity of the condition. When treating acute back problems:
- Rest. Avoid the activities that produce the pain (bending, lifting, twisting, turning, bending backwards, etc).
- Anti-inflammatory drugs and other pain medications.
- Apply ice in acute cases to the thoracic spine to help reduce pain and associated muscle spasm. Apply it right away and then at intervals for about 20 minutes at a time. Do not apply directly to the skin.
- Moist heat may be helpful to reduce pain and improve any feelings of stiffness.
- An exercise regiment designed specifically to address the cause of the symptoms associated with the degenerative joint disease and improve joint mobility, spinal alignment, posture, and range of motion.
- The use of a brace or other support may be necessary to reduce stress on the facet joints, muscles and thoracic spine.
- Steroidal medication to reduced inflammation in moderate to severe conditions.
- Facet joint injections directly to the involved joint.
- Physical therapy to reduce inflammation, restore joint mobility, improve motion, and help the return of full function.
In mild cases patients often found that rest, ice and medication were enough to reduce the pain. Physical therapy is recommended to develop a series of stretching and strengthening exercises to prevent re-occurrence of the injury. Return to activity should be gradual to prevent a flare up of symptoms.
Moderate to Severe Cases
If the problem persists, consult with your health care provider. Your physician will perform a thorough evaluation to determine the possible cause of your symptoms, the structures involved, the severity of the condition, and the best course of treatment.
In addition to performing a thorough examination your physician may order the following tests to make a more concise diagnosis:
- X-ray to determine if there is any joint degeneration, fractures, bony malformations, arthritis, tumors or infection present.
- MRI to determine any soft tissue involvement, including visualization of the discs, spinal cord and nerve roots.
- CT scans, which can give a cross section view of the spinal structures.
Medications to consider
Your physician may recommend several medication options individually or in combination to reduce the pain, inflammation and muscle spasm that may be associated with facet joint injuries.
- Over the counter medications for mild to moderate pain.
- If over the counter medications are not effective your physician may prescribe stronger pain medication.
- Anti-inflammatory drugs or prescription NSAIDS to reduce inflammation following acute injury.
- Muscle relaxers to reduce acute muscle spasm.
- Injections like facet injections, nerve blocks or an epidural. These may involve the injection of corticosteroids to a specific structure to reduce local inflammation.
Severe or Non-responsive Conditions
In the case of conditions that do not respond to conservative care, surgery may be indicated. If you continue to experience some of the following symptoms:
- Increase in radiating or radicular pain
- Pain or nerve irritation that gets worse
- Associated disc involvement
Injections like facet injections, nerve blocks or an epidural. These may involve the injection of corticosteroids to a specific structure to reduce local inflammation.
- Caudal Epidural Injections
- Facet Joint Injections
- Interlaminar Caudal Epidural Steroid Injections
- Medial Branch Blocks
- Selective Nerve Root Blocks
Surgical Procedures to reduce the affects of degeneration on pain producing structures of the spine.
- Endoscopic Decompression
- Endoscopic Foraminotomy
- Laser Facet Rhizotomy
- Facet Thermal Ablation
- Radiofrequency Ablation