What is Thoracic Anatomy?
The thoracic spine anatomy is the middle section of the spinal column between the neck and the lower back. The thoracic spine has a natural front to back curve, or kyphosis, providing balance to the entire spine and creating the space for the chest cavity. Similar to the anatomy of the lower, or lumbar spine, the thoracic vertebrae and disc structure is thinner and less flexible; this is due to the support the thoracic spine provides to the rib cage which has the important job of protecting vital organs. Each thoracic vertebrae attaches to its corresponding rib. There are 12 thoracic vertebrae ranked T1 to T12, top to bottom. These have the common structural components of vertebrae including bone, disc, and facet joints. The thoracic spine houses the spinal cord on its route to the L1 vertebrae where it leaves the body center and extends out to the entire lower body. Injury, degeneration or compression of the thoracic spine can affect the lower body as well as the chest which is also connected to thoracic spinal nerve roots. As a neurosurgeon, Dr. Ernest Braxton offers non-surgical and advanced minimally invasive surgical treatments for patients with conditions impacting the thoracic spine.
What Nerves are in the Mid Back?
The thoracic spine has 12 nerve root pairs each corresponding to the thoracic vertebrae above it. For example, the T2 nerve is below the T2 vertebrae and above the T3 vertebrae. The final thoracic nerve root, the T12, is between T12 and L1 at the top of the lumbar spine. All 12 thoracic nerve roots exit their vertebrae through the foramen, a bony hole within the vertebral structure. The thoracic nerve roots branch out into the front and back of the body typically in this pattern:
- T1 and T2 – top of chest into the arm and hand
- T3, T4, T5 – chest wall and pulmonary structure
- T6, T7, T8 – lower chest and abdomen
- T9, T10, T11 and T12 – abdomen and lower back
The structure and function of the thoracic spine can create issues for the thoracic nerves. Inflammation, compression, degeneration, and even severe muscle strain between ribs can create symptoms for patients both in the location of the nerve root and in the areas reached by the branching nerve endings. Symptoms can include pain, weakness, numbness, tingling and in some cases, breathing difficulty.
What Do Spinal Discs in the Thoracic spine Do?
There are 12 discs of the thoracic spine corresponding to the 12 thoracic vertebrae. All spinal discs are cushion-like and provide shock absorption for the spine. Thoracic discs are normally thinner than other spinal discs which helps contribute to the stability of the mid back. Only the top 10 discs interface with ribs. Each thoracic disc has the typical outer layer of tough collagen rings and the cushion-like center with its gel like interior. Spinal discs do not have blood vessels and therefore no blood flow. Uniquely, a super-thin structure between the disc and the vertebrae called the vertebral end plate does allow the flow of nutrients to the disc.
What are the Vertebrae in the Thoracic Spine?
There are 12 vertebrae in the thoracic spine. More than both the cervical and lumbar spine, the thoracic vertebrae have the unique function of connecting the ribs and providing stability to the upper body and a protective barrier for the critical organs within. With its normal outward curve, or kyphosis, the thoracic spine has a unique design for stability for the entire body. The vertebral body is a thick, bony structure located at the front of each vertebrae. The vertebral arch contains and protects the spinal canal. The facet joints at the back of each vertebrae connect each vertebrae, one to another. The costovertebral joints articulate to each rib, and functions to promote thoracic stability.
Are you experiencing spinal pain? Contact Dr. Braxton today.
What Causes Mid Back Pain?
The thoracic spine is more resistant to back pain than the cervical and lumbar spines. This can be partially attributed to the stabilizing function that the thoracic spine provides to the rib cage and rest of the body. Thoracic spinal pain is most often due to posture issues over time or to an injury that disrupts the sturdiness of the mid back. Rib cage muscles can become irritated by repetitive motion or deconditioning contributing to mid back pain; this is often diagnosed as intercostal muscle strain. Just like other sections of the spine, facet joints within the thoracic spine can develop dysfunctions, usually due to aging which can create thoracic pain. Aching muscles in the mid back along the shoulder and into the neck can be a type of thoracic pain that causes burning and sharp sudden pain in a specific location. If thoracic back pain limits a patient’s normal activities, an evaluation with Dr. Braxton can be beneficial.