PRACTICE CHANGER
Think twice before recommending vertebroplasty (VP) for symptomatic osteoporotic compression fractures. New studies suggest that it has little benefit; thus, VP should be considered only after other, more conservative options fail.1,2
STRENGTH OF RECOMMENDATION
A: Consistent, high-quality randomized controlled trials (RCTs)
Kallmes DF, Comstock BA, Heagerty PJ, et al. A randomized trial of vertebroplasty for osteoporotic spinal fractures. N Engl J Med. 2009;361:569-579.
Buchbinder R, Osborne RH, Ebeling PR, et al. A randomized trial of vertebroplasty for painful osteoporotic vertebral fractures. N Engl J Med. 2009;361:557-568.
ILLUSTRATIVE CASE
A 72-year-old woman with a history of osteoporosis is being treated with a bisphosphonate, calcium, and vitamin D. She’s in your office today because of the sudden onset of midline lower back pain after minor trauma. X-ray reveals an uncomplicated osteoporotic fracture of L2, with 50% loss of vertebral height. When she returns in a few weeks, the patient still has significant pain (7 on a scale of 0-10) that is not well controlled with hydrocodone and acetaminophen. Should you refer her for vertebroplasty?
Each year in the United States, approximately 750,000 vertebral fractures occur.3 The traditional treatments for osteoporotic vertebral compression fractures include bed rest, pain medication, braces, and therapy for osteoporosis. Since the late 1990s, however, vertebroplasty (VP)—the percutaneous injection of acrylic bone cement (polymethylmethacrylate, or PMMA) into the affected vertebra under radiologic guidance—has become the preferred treatment, particularly for painful vertebral fractures that do not respond to conservative treatment.
Widely used, but not much evidence
Despite a lack of rigorous scientific evidence of VP’s efficacy, the number of procedures nearly doubled from 2001 to 2005 among Medicare enrollees—from 45 per 100,000 to 87 per 100,000.4 A meta-analysis of 74 (mostly observational) studies of VP for osteoporotic compression fractures found good evidence for improved pain control in the first 2 weeks. At 3 months, the analysis found only fair evidence of benefit, and at 2 years, there was no apparent benefit.5
Complications are primarily related to cement extravasation, but are usually not symptomatic. The overall symptomatic complication rate is less than 4%.6 There is conflicting evidence regarding whether VP increases the risk of fracture in other vertebrae.7
Prior to the 2 studies reviewed in this PURL, there were only 2 RCTs comparing vertebroplasty with conservative medical management. The VERTOS trial8 randomized 34 people with osteoporotic vertebral compression fractures (of 6 weeks’ to 6 months’ duration and refractory to medical therapy) to either VP or conservative treatment. The VP patients had improved pain scores and decreased use of analgesic agents at 24 hours, compared with the conservative treatment group. But at the end of the 2-week trial, there was no difference in pain scores between the 2 groups.
The other RCT of VP vs conservative therapy randomized 50 patients with acute or subacute osteoporotic fractures (the average age of fracture was 6-8 days) to VP or conservative care.9 There was significant pain improvement in VP patients at 24 hours, but no significant difference in pain scores between the 2 groups at 3 months. This study was significantly flawed, however, because the researchers failed to collect pain measurements at study entry for a substantial number of patients.
STUDY SUMMARIES: Vertebroplasty lacks benefits
Both INVEST (the Kallmes study)1 and the Buchbinder study2 were blinded, randomized, placebo-controlled trials of VP. INVEST, performed at 11 sites in the United States, United Kingdom, and Australia, enrolled 131 patients. The Buchbinder study enrolled 78 patients at 4 sites in Australia. Both enrolled patients with painful osteoporotic fractures of less than 1 year’s duration. Exclusions for both trials included a suspicion of neoplasm in the vertebral body, substantial retropulsion of bony fragments, medical conditions that would preclude surgery, and an inability to obtain consent or conduct follow-up.
Participants in both trials had similar baseline characteristics: They were primarily Caucasian and female, with an average age in the mid-70s. The average pain intensity at enrollment was about 7 on a 0- to 10-point visual analog scale (VAS). The average time since the fracture causing the pain was 4 to 5 months in INVEST and about 2 months in the Buchbinder study. Both trials used appropriate randomization, blinding, and intention-to-treat analysis.
Blinding featured sham procedures. In both studies, the researchers used elaborate measures to ensure blinding: The control patients were prepped in the fluoroscopy suite as if they were about to undergo VP. They received local anesthesia down to the periosteum of the vertebra. The PMMA was opened and mixed in the room to allow its distinctive smell to permeate. Patients also received verbal and physical cues that simulated the procedure, and spinal images were obtained.
