Osteoporosis results in more than 700,000 vertebral fractures annually in the United States that, in turn, lead to 115,000 annual hospital admissions. They represent over 50% of all osteoporotic fractures and have an incidence roughly twice that of hip fractures.1
Many vertebral fractures are asymptomatic but are still associated with increased morbidity and mortality. Approximately 25–30% of these vertebral fractures are associated with a great deal of pain.
“About two in three people with an acute compression fracture of the vertebra will do well with conservative care such as braces, pain medications, and bed rest,” says Matthew Smuck, MD, assistant professor of physical medicine and rehabilitation at the University of Michigan in Ann Arbor. “Over time, the pain improves and there are few long-term deficits to contend with. There is, however, that last third that may have exquisite pain or have contraindications for bed rest or the use of pain medications, especially potent narcotics.”
Two Options Available in U.S.
For these patients, percutaneous vertebral augmentation (PVA) should be considered a viable alternative. There are two forms of PVA approved for use in the United States.
Vertebroplasty has been performed in the United States since 1995. In this procedure, polymethylmethacylate (PMMA) is introduced into the fractured vertebral body through a large needle. The PMMA stabilizes the fracture and improves pain.
The second option is known as balloon kyphoplasty (BK). A balloon tamp is inserted into the vertebral body to compress the bone, create a cavity, and attempt to realign the endplates. After removing the tamp, cement is injected to fix and stabilize the fractured vertebral body.
Indications for the use of PVA include a painful osteoporotic fracture that has not responded to conservative medical therapy for at least two weeks, compression fractures related to benign or malignant tumors, osteonecrosis, and structural reinforcement prior to surgical stabilization. These procedures should be performed with caution in those with an unstable fracture with movement, as these tend to be associated with more frequent PMMA leakage.
The guidelines suggest the appropriate person for [PVA] should have had a vertebral fracture with pain that has not resolved with at least two weeks of conservative treatment.
—Robin Dore, MD
Absolute contraindications to the procedure include an asymptomatic stable fracture, osteomyelitis of target vertebra, uncorrected coagulation disorders, acute traumatic fracture of non-osteoporotic or nonmalignant vertebra, an allergy to any of the components, and local or systemic infections. Relative contraindications include pain caused by a compressive syndrome unrelated to vertebral body collapse, fragment with more than 20% spinal canal compromise, tumor extension into epidural space, or severe vertebral body collapse (vertebra plana).
“The guidelines suggest the appropriate person for either of these procedures should have had a vertebral fracture with pain that has not resolved with at least two weeks of conservative treatment,” says Robin Dore, MD, clinical professor of medicine at the David Geffen School of Medicine at the University of California, Los Angeles. “It is also essential that an MRI be obtained to confirm that there is not a burst fracture present. PVA is contraindicated in that type of fracture because the cement can migrate and impinge on the spinal cord.” The most recent guidelines were published last year in the Journal of Vascular and Interventional Radiology.2
Although there have been no randomized trials comparing the two methods on outcome and efficacy, the guideline authors looked at the literature that was available on the subject. They stated, “The Societies [involved with the guidelines] have determined that the clinical response rates in individuals [treated with kyphoplasty] is equivalent to those seen in patients treated with vertebroplasty.” They also saw no proven advantage in pain relief, vertebral height, or complication rate.
Most of the complications associated with both procedures center around leakage of the PMMA. During injection, leakage of cement into the spinal canal can cause compression of the nerves or spinal cord that can lead to permanent neurologic injury even with surgical removal. Some instances of the cement entering circulation and then the lung causing an embolus have been reported. Rib fracture or pedicle fracture can occur during needle placement. Bleeding and infection are rare. Most series suggest a complication rate around 2%.
Two experts interviewed for this article still suggest caution. “One of the reasons we may not have seen a lot of ill effects is because they aren’t really being done on a routine basis yet,” says Elinor A. Mody, MD, associate physician in the division of rheumatology, immunology, and allergy at Brigham and Women’s Hospital in Boston. “As we know from recent experience with medications, the time we really find out about the downsides is when it becomes more widely used.”
Dr. Smuck says that while this may have been true five years ago, more recent data suggest that the reported complication rates are accurate even with the rapid growth in the number of physicians performing these procedures.
Are These Procedures Done Too Often?
There remains some concern about the need for some of these procedures in the first place. Dr. Dore notes that while studies report that 60% to 90% of patients are pain free within 24 hours, at six weeks, six months, and one year, there are no differences seen in quality of life between those getting one of the procedures and those treated conservatively.
“Most vertebral fractures heal within six weeks, so even with conservative treatment, there is usually complete pain relief within that time frame,” says Dr. Dore. “Doctors have jumped on the bandwagon for these procedures because they immediately relieve the pain. But we don’t yet have the data that indicates it is worth the morbidity and mortality to get a couple extra weeks of pain relief.” High levels of virtually overnight pain relief, however, are a major driver at both the doctor and patient level.
“Realistically, we don’t have a lot of treatments for the pain associated with acute vertebral fractures, and most of the options are bad,” says Dr. Mody. “Physicians are hard pressed to justify not doing the procedure when someone is in pain, the procedure is minimally invasive, and there are few bad outcomes.”
“BK does have some theoretical benefits, such as improving vertebral body height, which could improve posture,” says Dr. Smuck. “However, it still does nothing to correct sagital balance and forward stooping that results from multiple vertebral fractures. Even if it does increase vertebral body height, it doesn’t look like this translates to overall posture improvement.”
Price the Main Difference Between Procedures
The area where all three experts agree is there is a major difference is in the price of the two procedures. Most of the difference is that BK is coded as an open reduction and internal fixation procedure. This code requires that a patient be admitted to a hospital overnight before reimbursement will be approved. Therefore, BK costs about 2.5 times more than vertebroplasty.
In addition, BK requires a proprietary system that can cost up to $1,000 per patient. VP uses mainly PMMA and standard injection systems that are available off the shelf.
Another area of agreement is that prevention is much better than either procedure. “While this is a wonderful procedure that holds out hope of being very helpful, the most important treatment is to not let the fracture happen in the first place,” says Dr. Mody. “Early screening, medication, supplementation, and education will always be the mainstay of osteoporosis treatment.”
Kurt Ullman is a freelance writer based in Indiana.
