Whether or not vertebroplasty is an effective procedure has been a hot topic among spine surgeons and device companies since the publication of two studies in the New England Journal of Medicine and recently the American Academy of Orthopaedic Surgeons released a guideline recommending against the use of the procedure. The guideline was based on these studies that found vertebroplasty to have the same results as a “sham” procedure. However, many surgeons have experienced success with the procedure in their practices. Maarten Persenaire, MD, chief medical officer of Orthovita, discusses four reasons why vertebroplasty is still a relevant procedure.
In the guideline, AAOS moderately recommends calcitonin as pain medication for patients who present within five days of the fracture. All other treatment modalities, including conservative measures, are inconclusive, not recommended or only weakly recommended.
1. Not all literature has been reviewed. The guidelines are mainly based on the New England Journal of Medicinestudies which found that vertebroplasty produced the same results as injecting the patient with a local anesthetic. Problems with the actual conduct of these studies allow their findings, and thus the conclusions presented in the guideline, to be challenged. “The protocol didn’t require MRI evidence that the patient’s pain was caused by the fracture,” says Dr. Persenaire. “Thus the pain might have been caused by something other than a fracture. The researchers also had a hard time enrolling patients in the study, resulting in a population that is not necessarily representative of the patients most likely to benefit from the procedure. For example, no hospitalized patients, who tend to have the most severe pain, were included,” The restrictive review guidelines of AAOS also caused valid information from well executed non-randomized studies to be omitted.
2. Vertos II shows vertebroplasty effective. In developing the guidelines, AAOS reviewed literature published before Dec. 2009, says Dr. Persenaire. The AAOS did not include the Vertos II study supporting the effectiveness of vertebroplasty because it was published in The Lancet in August of 2010. “The selection criteria for patients in this study were much more clinically relevant than in the NEJM studies,” says Dr. Persenaire. “The MRI studies used in this study showed that there was an acute fracture. By the time the pre-operative evaluations were done, six weeks after the fracture, half of the patients had improved using optimized conservative care to such a degree that they no longer met the pain threshold for the study. The other half still experienced severe pain and was randomized to vertebroplasty or conservative care. In this group, the patients receiving vertebroplasty had significantly more relief of pain both early on and after one year.” Studies such as Vertos II confirm that vertebroplasty is effective for properly selected patients.
“It was a little surprising that AAOS came out with the vertebroplasty guidelines so quickly, when it was known that the Vertos II results were due any time” said Dr. Persenaire. “Vertebroplasty has been shown to be effective in many patients who have failed several weeks of optimized conservative care. The procedure should remain available to these patients, but I agree patient selection should be strict.”
3. Kyphoplasty is a more expensive alternative to vertebroplasty. AAOS guidelines gave a strong recommendation against vertebroplasty and a weak recommendation for kyphoplasty. “If people follow these recommendations, the healthcare costs related to this diagnosis are likely to rise because kyphoplasty is reimbursed at a higher level than vertebroplasty,” Dr. Persenaire says. “In my opinion, there are a certain percentage of patients who will experience additional benefits from using a balloon, but many patients would benefit equally from vertebroplasty.” While healthcare professionals are demanding a high level of evidence-based medicine, they are also seeking the most cost-effective way for patients to receive treatment.
4. There is an alternative to using PMMA during vertebroplasty. All of the published data on vertebroplasty and kyphoplasty are based on the use of classic bone cement, or PMMA. Because of the regulatory hurdles involved with developing a new implant material, most companies have only focused on developing new delivery tools for PMMA to make the procedure easier. The one exception so far is Cortoss, a bioactive composite developed by Orthovita, and an alternative to PMMA. FDA sanctioned studies that compared Cortoss to PMMA found that Cortoss patients on average had a better early response regarding pain and better long term function. “In addition, there were less re-fractures seen in Cortoss patients than in patients who received PMMA, and less material was needed to obtain a proper fill,” says Dr. Persenaire. Future developments in materials and instruments will further improve the effectiveness of the procedure.