Friday, March 19, 2010

Vertebroplasty Relieves Back Pain: New Evidence

VertebroplastyResults of several recently-announced large studies demonstrate that percutaneous vertebroplasty for treating vertebral compression fractures (VCFs) may provide significant and sustained pain relief. These investigations are in contrast to earlier reports that vertebroplasty is effective but no better than placebo.

Percutaneous vertebroplasty is an outpatient procedure performed under local anesthesia and involves injecting bone cement into one or more collapsed vertebral bodies [see illustration] that are causing back pain. Minimally invasive, the procedure stabilizes the fractures and expectedly stops the pain caused by bone rubbing against bone. It is indicated for painful VCFs that fail to respond to conventional medical therapy, such as minimal or no pain relief with back braces or medications. Two large studies demonstrating the effectiveness of vertebroplasty were presented at the Society of Interventional Radiology 35th Annual Scientific Meeting, March 13-18, 2010, and published as abstracts in the Journal of Vascular and Interventional Radiology. A third had been presented at the American Society of Spine Radiology's 2010 Annual Symposium in February.
  1. The first investigation, an observational study from Italy, involved 1,542 patients (1,302 females, mean age 73.5 ± 9.8 yrs) with collapsed vertebrae confirmed by MRI (1,204 with bone marrow edema), who were not improved by medical therapy lasting from 1.5 to 3 months and underwent vertebroplasty [Anselmetti et al. 2010]. At early followup (3 months), nearly all patients (1,494 or 96.9%) had dramatic and significant improvements in average pain scores on an 11-point visual analog scale (VAS), decreasing from at 8.2 baseline to 1.1 posttreatment (p<0.0005). Similarly, mean scores on the Oswestry Disability Questionnaire improved from 68.7 to 18.5 (p<0.0005). These positive outcomes were sustained at 12 and 18 month followup points. Among 757 patients wearing a brace before vertebroplasty, 683 did not need it afterward (p<0.0001).

  2. The second study was a prospective, multicenter, randomized controlled trial from the Netherlands [Klazen et al. 2010]. Researchers compared percutaneous vertebroplasty with conservative medical therapy in 202 patients with an acute vertebral compression fracture. Compared with controls, vertebroplasty provided better pain relief at day 1 (VAS 3.7 vs 6.7; p<0.001) and several intermediate time points up to 1 year (VAS 2.2 vs 3.8; p=0.014). During the first month after vertebroplasty, pain medication was significantly reduced compared with conservative therapy but this difference did not retain significance at longer followup intervals. The incidence of new fractures was similar in both groups during 1 year followup (p=0.28) and there were no serious complications or adverse events in the vertebroplasty group.

  3. The third study came from 6 Italian centers that reported exceptional outcomes in 4,547 patients undergoing percutaneous vertebroplasty [PRNewswire 2010]. The patients — 3,211 women and 1,336 men — each received an average of 3 vertebroplasty procedures for a total of 13,437 fractures. Within 48 hours, 86% of patients experienced significant pain relief (p<0.001) and this was sustained during 12 months of followup. No major neurologic complications were observed and only 430 (13%) patients required treatment for subsequent vertebral fractures during the followup period.
COMMENTARY: The authors of all 3 studies concluded that percutaneous vertebroplasty for VCFs is effective and safe; pain relief after the procedure is immediate, it is sustained during one year or longer, and other outcomes are significantly better than with conservative medical therapies. Together, the studies represent a large sample of nearly 6,300 patients receiving vertebroplasty for one or more fractures, which is an impressive body of evidence. However, two of the studies were observational without control groups and the third compared vertebroplasty with usual medical care (and this control group also had a meaningful decrease in pain during the followup period). Hence, there still may be concerns about the results of two placebo-controlled studies reported last summer in the New England Journal of Medicine, which we discussed in a blogpost at that time [here]. These investigations were smaller, including a total of only 209 patients, but they followed more of a “gold standard” RCT protocol in which patients were randomly and blindly assigned to receive either actual vertebroplasty or a placebo “sham” procedure. Compared with baseline measures, patients achieved clinically meaningful and roughly equivalent improvements in pain and disability after either the real or sham procedures.

There were some limitations of the two placebo-controlled trials; however, it is important to note that vertebroplasty was demonstrated as effective. This, plus the preponderance of evidence represented by the studies coming from Italy and the Netherlands, demonstrating immediate pain relief experienced by large numbers of patients, suggests that vertebroplasty may provide an important therapeutic option for patients with vertebral compression factures. Full reports on the latest studies have not yet been published, so we will watch the literature for further details and commentary on this topic in the months ahead.

REFERENCES:
> Anselmetti G, Manca A, Chiara G, et al. Abstract No. 16: Percutaneous vertebroplasty (PV) in the osteoporotic patients: Optimal indications and patient selection to improve clinical outcome. Personal experience in 1542 patients over 7 years experience. JVIR. 2010;21(2):S8-S9 [
available here].
> Klazen CA, Lohle PN, deVries J, et al. Abstract No. 11: Percutaneous vertebroplasty versus conservative therapy in patients with an acute osteoporotic vertebral compression fracture. Vertos II: A randomized controlled trial. JVIR. 2010;21(2):S6-S7 [
available here].
> PRNewswire. Multi-Center Data in a Large Series of Patients Show Vertebroplasty Provides Dramatic and Lasting Pain Relief for Vertebral Compression Fractures. Online news release, 2010(Feb 17). From a presentation at the American Society of Spine Radiology's 2010 Annual Symposium, February 2010, titled "Percutaneous vertebroplasty: results and complications in 4547 patients treated in six Italian EVEREST (European Vertebroplasty Research Team) centers” [
news release here].