The thoracic spine extends from the shoulders to the upper abdomen and articulates with the ribs and shoulders. It consists of 12 vertebrae separated by cartilaginous discs that serve as shock absorbers and facilitate movement between the vertebral segments. Between each set of vertebrae, spinal nerves emerge to supply nerve impulses to the muscles and organs of the body. A thoracic spine injury can cause symptoms in the immediate structures surrounding the injury, or to the organs supplied by the nerves that originate in that region.
Pain
The University of Maryland Medical Center notes that the lower thoracic spine is the most frequent area affected by compression fractures, which are fractures in which the body of the vertebrae collapses on itself. These fractures are often the result of too much load on the bone, which is a concern especially for those bones that have been weakened by osteoporosis. The pain caused by an acute compression fracture of the lower thoracic spine can be severe and can radiate into the lower back or legs. Movement may make the pain worse.
A more gradual erosion and compression of the lower thoracic vertebrae may cause milder pain or no pain at all.
Numbness
There is the possibility of injury to the spinal cord itself when the lower thoracic spine is subject to trauma. This can result in a loss of sensation, or the experience of a tingly pins-and-needles feeling known as paresthesia, according to the American Academy of Orthopaedic Surgeons.
Trauma to the thoracic spine can result in disc herniation, wherein a portion of the cartilaginous disc that separates two thoracic vertebrae ruptures and extends beyond the normal circumference of vertebrae. The herniated disc can press on nerves and cause numbness and tingling to extend down into the legs.
Bowel and Bladder Dysfunction
The nerve supply to the organs of excretion may be weakened due to injury to the lower thoracic spine, according to the AAOS. Urinary or fecal incontinence are a possible result of a herniated lower thoracic disc, as the impingement weakens nerve function and lessens the individual's ability to sense fullness in the bladder or bowels. This symptom should be regarded seriously, as it may indicate the need for immediate surgery, the University of Maryland Medical Center warns.
