The North American Spine Society and the Society of Interventional Radiology have pointed to flaws in both studies. And earlier studies, published over 15 years, found major benefits to kyphoplasty and a related procedure called vertebroplasty.
"We're missing opportunities for patients to receive a safe and effective treatment that can significantly reduce their pain and disability," said Malamis, an interventional radiologist.
The procedures are used to treat vertebral compression fractures in patients with osteoporosis and other conditions that result in brittle bones. In a vertebroplasty, an acrylic cement is injected into a fractured vertebra. In a kyphoplasty, a balloon-tipped catheter first is inserted into the fracture. The balloon is inflated to restore the height and shape of the vertebra before the cement is injected.
Neva Nelson, 74, of Naperville, Ill., said a kyphoplasty that Malamis performed in October, 2009, has greatly reduced her pain in a vertebra in her lower back that she fractured after falling on ice. Before her kyphoplasty, Nelson had to sit on cushions. Walking, and especially standing, were painful. "I had to do something," she said. "I could not go on like that."
Nelson said that since undergoing her kyphoplasty, "I don't have to worry about my back any more."
In the controversial studies, patients were randomly assigned to receive a vertebroplasty or a placebo-like "sham" procedure. In the sham procedure, patients received an injection of anesthetic, but no cement.
However, patients in severe pain are reluctant to enroll in a trial where there's a 50 percent chance of receiving a sham treatment. In one of the studies, researchers had to screen 1,813 patients to enroll just 131 subjects. In the other study, only 78 of 219 eligible patients were enrolled. This low enrollment rate raises the possibility that the patients who did enroll were not representative.
Patients experience the greatest pain during the first three months after a compression fracture. Thereafter, pain gradually subsides. Thus, a vertebroplasty or kyphoplasty provides the greatest benefit when performed within a week or two of the fracture. But the studies enrolled patients up to 12 months after fractures.
In addition to reducing pain and disability, a kyphoplasty can reduce the risk of subsequent fractures by improving the angle and height of the spine. The studies evaluated vertebroplasty alone, and did not include the more innovative and very different kyphoplasty procedure.
Malamis suggests the medical community wait for the results of additional studies now underway before passing final judgment on vertebroplasty or kyphoplasty. In the mean time, he notes that Medicare still covers the procedures.
David Haow on 13 Jun 21The contamination and potential ecological risk posed by heavy metals from thirteen (13) sediment samples from different sampling sites along the lower portion of Agusan River were analyzed and assessed using different pollution indices. The results obtained shows that the total digest concentrations of different heavy metals under investigation have the following order: Cd < Pb < Zn < Mn, for both first sampling periods. The speciation and distribution pattern have shown that significant amounts of all metals are present in the residual fraction. Similarly, oxide-bound and organic-bound fractions were found to be highly important for Zn and Mn while Cd and Pb were significantly associated in the residual and exchangeable fractions. The results of different pollution indices moreover, showed that among all the heavy metals being studied, Cd posed the highest environmental risk across all sampling stations in both sampling periods and Mn metal was highly enriched and abundant in all of the sampling stations. Importantly, PCA results suggest that Zn, Mn and Pb may have the same origin while Cd might be coming from different sources, and this is corroborated well with the cluster analysis results. The results obtained from this work provide baseline data on the assessment of heavy metal pollution in the lower portion of Agusan River. Importantly, the acquired environmental indices will certainly help safety managers in assessing and interpreting the potential risk of the sediment associated chemical status that might adversely affect aquatic organisms in the selected sampling sites.
