The adult spinal column consists of 33 vertebrae. Beginning at the neck, there are 7 vertebrae in the cervical spine (topmost portion of the spine), 12 vertebrae in the thoracic spine (middle portion of the spine), 5-6 vertebrae in the lumbar spine (second last portion of the spine) and 3 vertebrae in the coccyx (tailbone).
The vertebra is separated by intervertebral disc, which house a gelatinous material within themselves called the nucleus pulposus. When these discs degenerate due to age or injury, they can rupture, allowing the gelatinous material within to seep into the spaces between vertebrae. Compression of the spinal nerve roots can result if this material pushes against the nerves exiting the spinal column. This can lead to symptoms such as pain, tingling, numbness, and loss of mobility.
Pain that can be caused due to various factors affecting changes in the thoracic spine with the main symptom onset as and of pain is referred to as thoracic disc pain.
The pain can be as a result of a herniated disc, thoracic degenerative disc disease or trauma to the upper back. The trauma in turn can result in the former two problems developing over time or immediately.
Classification And Types of Thoracic Disk Pain
Herniated Disc: A herniated disc can occur when the inner gelatinous material of an intervertebral disc leaks out of the inside of the disc. A thoracic herniated disc can cause upper back pain and other symptoms, such as radiating pain or numbness.
Specific symptoms of a thoracic herniated disc are usually different depending on where the disc herniates, as the herniated disc material in the upper back can either impinge on an existing nerve root or on the spinal cord itself.
Thoracic Degenerative Disc Disease: Thoracic disc disease is conceptually similar to disc disorders in the cervical and lumbar spine, but symptomatic lesions (anatomical problems related to the symptoms) are far less common.
The most common location for thoracic disc disorders is at the thoracolumbar junction (T8-T12) in the mid back. The true incidence is unknown because many thoracic disc disorders do not cause thoracic back pain or other symptoms, and they comprise only a very small percent of all herniated disc treatment surgeries.
Epidemiology of Thoracic Disk Pain
Recent review states that range of prevalence estimates thoracic back pain in general population to be extremely broad due to many factors, which includes different definitions and length of thoracic back pain.
Results of Review for Thoracic Disk Pain Are As Following:
- Studies reported thoracic back pain being highly prevalent in children and teenagers, especially females.
- In children and teenagers, this pain was associated mostly with females as well as postural changes, backpack use, weight of backpack, musculoskeletal symptoms, participation in sports, chair height in school, and problems with homework. Compromised mental health and transitioning from early to late adolescence also posed significant risk.
- In adults, this pain was associated with underlying other musculoskeletal symptoms and difficulty with performing ADLs.
Pathophysiology of Thoracic Disk Pain
Herniated Disc: Importance of “chemical radiculitis” is now recognized in production of back pain. Primary focus of surgery is to eradicate pressure or reduce compression on neural element, either spinal cord or nerve root, but it is also recognized that back pain instead of being only due to compression cam also be as a result of chemical inflammation. There is evidence pointing to specific inflammatory mediator of this pain. This inflammatory molecule named tumor necrosis factor-alpha is released not only in cases of herniated discs, but also annular tears by facet joints. In addition to causing pain, TNF also contributes to degeneration of disc.
Thoracic Degenerative Disc Disease: A normal intervertebral disc contains nucleus pulposus surrounded by anulus fibrosus. Both anulus and nucleus contain collagen and proteoglycans. Nucleus contains slightly more proteoglycans giving it a looser gelatinous texture. It blends with surrounding anulus without clear demarcation. Anulus has more collagen and this collagen becomes progressively compact and tough at its periphery. The outer anulus is connected to adjacent vertebral bodies at the site of fused epiphyseal ring by Sharpey’s fibers and to anterior and posterior longitudinal ligaments. Normal discs are adequately hydrated with nucleus containing about 85% water and anulus about 75%.
Along with cartilaginous endplates of adjacent vertebral bodies, intervertebral disc forms a disc complex, which gives structural integrity to interspaces and cushions mechanical forces applied to spine.
Due to aging, certain chemical and structural changes start to occur in intervertebral discs with resultant increased ratio of keratan sulfate to chondroitin sulfate and as a result proteoglycans lose their close connectivity with disc collagens. Disc also loses its water-holding capacity and water content start to decrease.
Vertebral endplates also start to become thin. This degree of degeneration is considered to be a normal part of aging.
With more advanced degeneration, dense fibrous tissue replaces normal fibrocartilaginous structure of nucleus pulposus leaving no difference between nucleus and anulus fibrosus. Development of anular tears weakens anulus and allows nucleus to extend into defect. Tears that extend through outer anulus induce growth of granulation tissue and hasten degenerative process. Advanced degeneration also leads to gas formation or calcification within disc. Also, fissures develop in cartilaginous endplates and regenerating chondrocytes and granulation tissue form in that area.
Etiology And Risk Factors of Thoracic Disk Pain
- Thoracic back pain maybe as a result of trauma, injury, strain or poor posture with time.
- Most general reason for thoracic back pain appears to stem from muscular irritation or other soft tissue issues. These can come up due to lack of strength, poor posture, sitting in front of a computer for prolonged periods, use of a backpack, overuse, trauma.
- Asymptomatic form of this disc herniation is quite common but symptomatic forms are rarely found.
- Thoracic spine is quite a common site for inflammatory, degenerative, infective, and neoplastic conditions.
- Thoracic back pain is associated with conditions like osteoporosis, ankylosing spondylitis, osteoarthritis etc.
Signs And Symptoms of Thoracic Disk Pain
Signs And Symptoms of Herniated Disc
Herniation of uppermost thoracic discs can mimic cervical disc herniations. Symptoms affect back of skull, neck, shoulder girdles, scapula, shoulders, arms, hands. The nerves of cervical plexus and brachial plexus may get affected whereas herniation of other discs mimics lumbar herniation.
Herniation of lower thoracic discs mimics lumbar herniation. Symptoms affect lower back, buttock, thigh, genital areas, and can also radiate into foot or toe. Most commonly affected nerve is sciatic nerve resulting in symptoms of sciatica. Femoral nerve can also get affected causing patient to experience numb and tingly feeling in legs or feet. There may even be a burning feeling in hips and legs.
Signs And Symptoms of Thoracic Degenerative Disc Disease
- Pain upon twisting of the back.
- Muscle spasms.
- Bowel or bladder dysfunction.
- Slumped posture.
Treatment for Thoracic Disk Pain
Treatment for Herniated Disc
In most instances, spinal disc herniation does not require invasive procedures. A study conducted about sciatica that is generally caused by spinal disc herniations found after about three months of symptoms around 75% of people showed considerable improvement without invasive procedures.
In the beginning, treatment is usually done with nonsteroidal anti-inflammatory medications but again prolonged use of these medications in people with persistent back pain is complicated by possible cardiac and GI toxicity. An alternative for this which is often done is cortisone injection into spine adjoining suspected pain generator. This is called ESI or epidural steroid injection. ESI generally results in improvement in pain when assessed after a month post injection. In certain settings, however, these injections may cause serious complications.
Rehabilitation, PT, chiropractic, antidepressant medications, etc… are all useful alternatives to anti-inflammatory approaches.
Treatment for Thoracic Degenerative Disc Disease
Degenerative disc disease treatment options range from simple bed rest to extensive surgery, so the treatment plan recommended for your case can depend on several factors such as your age, your overall health, and how significantly the pain is limiting your life and activities.
Examples Of Degenerative Disc Disease Treatment Possibilities Include :
- Physical therapy
- Chiropractic and alternative treatments.
Prognosis for Thoracic Disk Pain
Herniated Disc: Most people will improve with treatment. However, you may have back pain even after treatment. It may take several months to a year or more to go back to all of your activities without having pain or straining your back. People who work in jobs that involve heavy lifting or back strain may need to change their job activities to avoid injuring their back again.
Thoracic Degenerative Disc Disease: Thoracic disc degeneration is chronic and irreversible. Acute episodes of pain and weakness may be self-limiting, not exceeding a few weeks. The outcome depends on the activity level of the individual and adherence to recommendations for exercise and maintenance of normal activity. The prognosis for relief of symptoms with conservative treatment is good for most individuals. The presence of chronic illness such as osteoporosis or osteoarthritis, or pre-existing spinal deformity, may accelerate or complicate disc degeneration.