 |
 |
 |
 |
Spinal Compression Fractures
Most healthy bones can withstand substantial forces. If the force is too great for the vertebrae to sustain however, one or more of them can fracture. If the bone is too weak to withstand normal pressure, it may not take much force to cause the vertebral body to collapse.
Compression fractures of the spine usually occur at the bottom part of the thoracic spine and the first vertebra of the lumbar spine. They can be extremely painful and can cause neurological disfunction such as leg weakness or disturbances in bowel or bladder function.
Causes
Compression fractures of the spine are caused by excessive forces on the vertebral body. This usually results from a combination of bending forward and downward pressure on the spine. The fracture occurs when the bone actually collapses and the front (anterior) part of the vertebral body forms a wedge shape. The front of the vertebral body is crushed, or compressed. In very severe compression fractures (fortunately not a common occurrence), the back of the vertebral body may actually protrude into the spinal canal and put pressure on the spinal cord.
Underlying causes can include:
- Osteoporosis. Vertebral fractures most commonly arise due to severe osteoporosis, a progressive loss of bone mass most often seen in post-menopausal women. Osteoporosis thins the bones, often to the point that they are too weak to bear normal pressure. The thinning bones can collapse during normal activity, leading to a spinal compression fracture. Forty percent of all women will have at least one by the time they are 80 years old. These vertebral fractures can permanently alter the shape and strength of the spine. The fractures often heal without medical intervention and the pain eventually goes away. However, sometimes the pain can persist if the crushed bone fails to heal adequately.
In severe cases of osteoporosis, actions as simple as bending forward can be enough to cause a spinal compression fracture. This type of vertebral fracture causes loss of height and a humped back, especially in elderly women. This disorder (called kyphosis or a "dowager's hump") is an exaggerated forward curvature of the spine that causes the shoulders to slump forward and the top of the back to look enlarged and humped. - Trauma to the spinal vertebrae can also lead to minor or severe fractures. Such trauma could come from a fall, a forceful jump, a car accident, or any event that stresses the spine past its breaking point.
- Metastatic Disease. Another cause of vertebral fractures is a metastatic disease — the spread of cancer cells from their primary site into other areas of the body. The bones of the spine are a common place for many types of cancers to spread. A compression fracture of the spine that appears for little or no reason may be the first indication that an unrecognized cancer has spread to the spine. The cancer causes destruction of part of the vertebra, weakening the bone until it collapses.
Symptoms
If the fracture is caused by a sudden, forceful injury, you will probably feel severe pain in your back, legs, and arms. You might also feel weakness or numbness in these areas if the fracture injures the nerves or the spine. If the bone collapse is gradual — such as a fracture from bone thinning, the pain will usually be milder. There might not be any pain at all until the bone actually breaks.
Diagnosis
In order for a fracture to be diagnosed, your doctor will take your complete history and physical examination. There are many possible internal causes of pain. It is important to determine the root of the problem. After the physician has a better idea of what is causing your discomfort, diagnostic tests of some sort may be recommended.
Physical examination. If a compression fracture is suspected, the doctor will also test for point tenderness near specific vertebrae. Testing specific areas for unusual tenderness allows the doctor to narrow down the cause of your pain.
A neurological exam will also be given, allowing the doctor to test your reflexes, muscles, and sensory perception. Abnormalities on the neurological examination can point to nerve damage. The nerves of the spinal cord carry messages from the brain to the rest of the body. If there is damage to the spinal nerves, your body movement and neurological responses will be affected.
X-ray. If a fracture is thought to exist, an X-ray of the spine will generally confirm its presence. An X-ray is a painless process that uses radioactive materials to take pictures of bone. X-rays show bones, but not much soft tissue, so X-rays will definitely be used if fractures are suspected.
CAT (or CT) scan. Your doctor may also order a CAT scan to make sure that the fracture is stable. With a compression fracture, an up and down perspective of the spine will be pieced together for examination of stability. The CAT scan provides the most detailed view of the bones
MRI. If there is a chance that nerves are involved in the fracture, or if there is some question about what is causing the pain, an MRI might be recommended. The MRI is able to cut through multiple layers of the spine and show any abnormality of soft tissues, such as nerves and ligaments.
A nuclear bone scan is another diagnostic test that might be ordered. This test helps determine the age of a fracture. If the fracture is old and there appear to be other fractures that have healed, this may indicate osteoporosis (bone-thinning disease) is causing the fractures. In this case, treatment of the fracture will include preventive measures to try to stop other vertebral fractures from occurring. Such treatment could include: calcium supplements, increased vitamin D, weight-bearing exercises, and hormone replacement therapy for women.
Treatment
The most common treatments for a thoracic compression fracture are:
- Pain medications
- Decreasing activity
- Bracing
- In rare cases, surgery may also be necessary.
Your doctor may prescribe a back support (often officially called an orthosis) to support he back and keep you from bending forward. It holds the spine in hyperextension (meaning more extension, or straightening, than normal). This takes most of the pressure off the fractured vertebral body, and allows the vertebrae to heal. It also protects the vertebra and stops further collapse of the bone. The brace is well molded to conform tightly to your body, like a cast for any other fracture.
Vertebral fractures usually take about three months to fully heal. X-rays will probably be taken monthly to check on the healing progress.
While surgery is rarely needed, vertebroplasty or kyphoplasty ("cement injection") may be considered if there is evidence of sudden and serious instability of the spine. For instance, if the fracture leads to a loss of 50% of the vertebral body's height, surgery might be necessary to prevent damage that is more serious to the spinal nerves. Internal fixation is used to hold the vertebrae in the proper position while the bone heals. If there are signs that there is too much pressure on the spinal cord, the bone fragments pushing into the spinal cord may also need to be removed.
