Vertebral Body (Spinal) Compression Fractures

Osteoporosis is weakening of the bones due to consumption of calcium mineral stored in the bone matrix. This results in overall weakening of the bones making them susceptible to fracture or collapse under normal stresses. Osteoporosis affects all people with age, especially those with smaller amounts of stored calium, women more than men, and Caucasian and Asian women more than African Americans. Back pain is a common and costly problem in Western countries. It is estimated that back pain periodically incapacitates up to 20% of the American workforce at an annual cost of more than $24 billion in lost productivity and treatment. Pain of spinal origin has a lifetime prevalence of greater than 60% and an annual incidence of 5%. It is estimated that 25% of American women over the age of 50 will suffer at least one vertebral fracture.1 Compression fractures represent a common cause of life-threatening disability in the elderly and are now readily treated using minimally invasive techniques.

A flexible column which consists of a series of bones stacked one on top of the other.

Anatomy of the Spine
The spine is a flexible column which consists of a series of bones stacked one on top of the other. These bones are known as vertebrae. There are usually 33 vertebrae in the spine, divided into five categories: 7 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal.

Discs comprised of fibrous and cartilaginous tissue separate the vertebra from the second cervical level to the sacrum. Their purpose is to permit and cushion normal movement.

The spinal cord connects the brain to the rest of the body. It is a thin column of nerve tissue protected within the spinal canal. The spinal cord terminates usually at the L1 (first lumbar) vertebral level.. Dorsal and ventral nerve roots arise from the spinal cord at each vertebral level and exit the spinal canal through foramena, or openings, between each vertebra. Sensory and motor nerves extend throughout the body to connect them with the central nervous system.

Thoracic and lumbar vertebrae are most commonly affected by compression fractures. This region of the spine is ordinarily subjected to significant loading forces. Extreme, sudden, or abnormal movements can lead to injury. Fractures of the vertebrae can be due to several causes. An accident or trauma can lead to fractures. Vertebral fractures may also be due to osteoporosis—decreased bone strength due to lack of calcium. Tumors within the vertebrae are also a cause of bone weakening and can lead to spinal fractures fractures and severe pain.

When an accident or trauma causes a spinal fracture, the spinal column may be unstable, or bone fragments may compress the spinal cord or the nerve roots exiting the spinal foramena. In such cases, treatment may require surgery with spinal fixation or immobilization braces. However, when osteoporosis or tumors cause generalized weakening and fracture of the vertebra, surgery with spinal fixation is often not possible or involves considerable risk. Severe pain may limit mobility, but bedrest is notan effective treatment, as it can exacerbate osteoporosis and lead to other medical complications such as pneumonia. These very painful fractures are often treated through a procedure called vertebroplasty. “Vertebro” refers to the vertebrae and plasty mans “to form.” Vertebroplasty forms a support for the fractured vertebrae Percutaneous treatment is used for two common causes of spinal pain: facet joint arthropathy and osteoporotic vertebral compression fractures. Vertebroplasty, the use of cement to stabilize vertebral fracture fragments to palliate spinal pain, may become the new standard of care for management of pain and disability due to either osteoporotic or neoplastic compression fractures. Vertebral collapse most commonly occurs during normal exertion and loading forces in elderly persons with osteoporosis. 1.5 million osteoporotic fractures occur each year including 700,000 vertebral fractures. The lifetime risk of symptomatic vertebral compression fractures is 16% for white women and 5% for white men. Vertebral compression fractures are defined by 15% loss of vertebral height and classified by morphologic deformity. The most commonly compressed vertebral bodies are T8, T12, L1, and L4. Symptomatic fractures cause severe pain and hospitalization in 8%, and prolonged nursing care in 2%. The result can be life-threatening pneumonia, immobilization and deep venous thrombosis, loss of independence, and depression. Mortality rates are 1.23 times higher in women with compression fractures than in age-matched controls.

Vertebroplasty was introduced in Europe in 1984, first published in the medical literature in 1987, and has been performed in the United States since 1995. It is a very effective procedure with a high success rate and very low probability of risk.2,3 This technique entails the insertion of a needle, under x-ray guidance, throught the skin and into the vertebral body under local anesthesia. Medical cement (PMMA, polymethyl-methacrylate) is injected which stabilizes the fracture to prevent pain and strengthens the bone to prevent further collapse. In properly selected patients, the end result is usually rapid pain relief and and greatly improved mobility . This procedure comes with low risk (less than one percent in my experience and in most published series), although potential complications such as infection, nerve injury, bleeding, and pulmonary embolism should be discussed with the physician.

Candidates for vertebroplasty
Although postmenopausal women are at greatest risk of developing osteoporosis, a thinning and fragility of the bones, men are also affected. When osteoporosis occurs, calcium and other substances become lost from the bones. Eventually, they may become so weak that they cannot support themselves and will ultimately collapse. This is known as a compression fracture. Although compression fractures are most commonly due to age-related osteoporosis, bone weakening can also be caused by long-term steroid use, benign blood vessel tumors, and malignant tumors that often metastasize to the spine.

Compression fractures frequently but do not always heal over time, and the process of waiting for recovery may be prolonged and can be extremely debilitating. Other illnesses may develop while one is immobile and awaiting recovery. Painkillers, back bracing, and bed rest may not alleviate the discomfort.4 Mortality rates are increased 1.23 times in women compression fractures compared with age-matched controls.

People who suffer from pain due to compression fractures typically experience a sudden onset of back pain localized to one spot. Vertebroplasty can usually alleviate such pain. The pain may also radiate to the front. Sciatica, which involves low back pain radiating down the buttock and leg, may also be present.

Not everyone with these symptoms is a candidate for vertebroplasty. The procedure should not be performed on people who have an active infection, coagulopathy (a bleeding condition in which the blood does not clot normally), or certain forms of fractures in which bone fragments press on the spinal cord or the nerve roots exiting the spinal cord.4

What to Expect when Undergoing Vertebroplasty
The day of the procedure, you will be brought to the operating room suite. The procedure will usually be performed with the patient in the prone position (lying on the stomach). For someone with severe back pain, this could be painful, so some anesthesia is useful to control any discomfort related to lying in the prone position with a pillow under the chest or stomach. Your arms will be placed straight outover your head in the “Superman” position. Sedatives and pain medications are administered intravenously by a nurse or an anesthesiologist who also monitors heart rate, blood pressure, breathing and oxygen levels. Most patients tolerate this procedure very well while awake and do not find it painful. However, spinal fractures can be very painful. Sometimes, general anesthesia is warranted to control the pain until the vertebroplasty has been performed.

To begin, the skin on the back immediately covering the fractured vertebrae will be washed with special soap. Sterile sheets and towels will then be draped over the area. A numbing medication (usually a combination of lidocaine, marcaine, and sodium bicarbonate) will be injected into the skin overlying the fractured vertebra. Then, a special needle will be placed into the fractured vertebrae under x-ray guidance using a fluoroscope – a special low-dose x-ray machine. Once the needle is in place, the physician may confirm needle position by injecting a small amount of x-ray dyeto allow the doctors to see the tiny veins (the blood vessels within the vertebra) and to make sure there are no abnormal blood vessel connections. This helps to ensure that the doctors have placed the needle in the appropriate place before administering the cement. As soon as the needle is confirmed to be in the appropriate location, treatment will begin.

The PMMA cement is mixed with barium or tungsten powder which makes it visible on the fluoroscope. Once the cement and accompanying ingredients are all mixed together, it becomes liquefied. The doctors will be able to watch the mixture entering into the bone. An antibiotic is usually also added to the mixture to reduce any risk of infection. The cement hardens very quickly, so the doctors need to proceed accurately and rapidly. Only a tiny amount of cement is needed to perform the procedure. Usually, between 2 and 5 cc of cement are instilled into a single vertebra, and the results do not appear related to the overall amount of cement instilled. Once they have determined (by viewing the injection on the x-ray screen) that a sufficient amount of the cement has been injected into the fracture, the needle is removed. The only visible evidence that the procedure took place is a band-aid; no stitches are required. The puncture hole is usally 1-2 mm and usually heals in 24 hours.

The vertebroplasty procedure, the injection of cement, is very brief and may take only minutes. The total length of time for the entire procedure takes one to two hours, depending on specific circumstances. Most of the time is required to make the patient comfortable and covered with the sterile drapes and towels. Patients who may have several affected vertebrae or who need general anesthesia will require a longer procedure.

Following the Procedure
Once the procedure is completed, the patient is placed in the supine position (lying on the back) for approximately two hours while the cement hardens. During this time, patients often visit with friends or family, enjoy a meal and watch television. Unless the procedure is performed late in the afternoon or the patient has other medical problems that require other treatments, patients are usually able to go home the same day.

A friend of family member must be available to bring you home. Strenuous activity will be limited at first, but normal activities will gradually be increased. Some patients feel so well after the procedure that they are at risk to injure another vertebra, It is important to remember to limit activity, especially heavy lifting. A good rule of thumb is to not lift anything heavier than a purse or small bag of groceries for at least one week.

Follow-Up Care
Your doctor may recommend rehabilitation following the procedure. This may take the form of supervised physical therapy or independent exercise. Your doctor may give you written suggestions for exercises you can do at home. Regardless of the recommendations, your physician may want to see you several times in the weeks following the procedure. Most patients will eventually be able to resume normal activity and discontinue or reduce their use of pain medication. Dietary modifications, vitamin therapy, new medications, and judicious exercise are all necessary to curtail or reverse the bone loss (demineralization) causing osteoporosis.

Many patients report feeling relief from back pain within a few days. No prospective, randomized trial has been completed. In retrospective case series, immediate pain relief was achieved in 70-90% with complication rates less than 1%. In one series, 12% of treated patients developed additional fractures requiring intervention, but there was no increased risk of new spinal compression fractures in treated patients. In a small prospective trial, 21 patients had vertebroplasty and 19, medical therapy, early results suggested a benefit to vertebroplasty.

If this is not the case, reevaluation is warranted to determine if other causes may be contributing to the pain. Back pain is often caused by many different factors at the same time. Another possibility is a new compression fracture at a different location. Whatever the cause, open communication with your doctor is extremely important.