Between each thoracic vertebra lies a fibrocartilagenous structure called the intervertebral disc. This disc is present at all levels of the thoracic spine. The intervertebral disc is comprised of a series of outer fibrous rings (annulus fibrosis) and a gelatinous center (nucleus pulposus). The walls of the disc are thinnest and weakest posterior laterally where the spinal nerves exit the spinal column. The disc serves as a joint between the vertebrae, functions as a cushion and allows movement between the vertebrae.
Inflammation, damage or degeneration of a thoracic disc can cause a range of symptoms, which vary based on the severity of the problem. Disc pathology may produce a loss of back motion, back pain, pain that radiates from the back around the ribs and chest, numbness, tingling, muscle spasm or some combination of these symptoms. The thoracic level with the highest rate of disc degeneration and bulging is T8-T12. The incidence of thoracic disc problems is far lower than in the lumbar and cervical area.
What is a Bulging Disc?
When the outer walls (annulus) of the disc become weak the nucleus polposus can push the walls out creating a bulge. Bulging discs are common and may be asymptomatic. They can occur as part of the aging process. If the bulge does put pressure on the nerves and surrounding soft tissue it can become symptomatic.