No Evidence to Support Use of Recent Joint Replacement Systems, Systematic Review ShowsSep 19, 2014
Recent “innovations” in joint replacement systems may not be worth the risk, a scientific analysis found. In a systematic review published online September 9th in the BMJ, researchers said that they failed to find evidence supporting the use of newer devices.
“We did not find convincing high quality evidence supporting the use of five substantial, well known, and already implemented device innovations in orthopaedics. Moreover, existing devices may be safer to use in total hip or knee replacement. Improved regulation and professional society oversight are necessary to prevent patients from being further exposed to these and future innovations introduced without proper evidence of improved clinical efficacy and safety.” the authors wrote.
The review, which looked at 118 studies involving a total of 15,384 implants in 13,164 patients, focused on five joint replacement innovations: ceramic-on-ceramic bearings, modular femoral necks, uncemented monoblock cups, high flexion knee replacement and gender specific knee replacement. All of the devices have met three criteria: there must be a rational explanation as to why they would be better, they must have a 90 percent reported completed in a national orthopedic registry and they must be similar to an older device used for the same purpose.
Metal-on-metal hip replacements, which have become controversial due to a high rate of failure and other safety concerns, were not included in the study. The U.S. Food and Drug Administration (FDA) issued cautionary guidelines last year stating that the rate of revision surgery is higher with all-metal hip devices, and warned that metal-on-metal hip implants have a risk of releasing metal debris into the bloodstream.
The researchers found that “None of the five device innovations was found to improve functional or patient reported outcomes. National registries reported two to 12 year follow-up for revision occurrence related to more than 200 000 of these implants. Reported comparative data with well-established alternative devices (over 1 200 000 implants) did not show improved device survival.” Furthermore, they discovered a higher rate of revision with modular femoral necks, ceramic-on-ceramic bearings and high flexion knee implants compared to their traditional counterparts.
The revision rate was almost double with modular femoral neck replacements, at a hazard ratio of 1.9. The hazard ratio for high-flexion knee replacements ranged from 1.0 to 1.76 among 56 studies; ceramic-on-ceramic hip replacements had an elevated risk ranging from 1.0 to 1.55 compared to ceramic-polyethylene in 42 studies. The findings prompted the authors to call for greater oversight to when approving so-called innovations to devices such as joint replacements.
"[N]ew technologies are being introduced to the commercial market without sufficient high quality evidence for improved benefit over existing, well proven, and safe alternative implant solutions...[T]he status quo regarding the introduction of new device technologies is not acceptable." wrote lead author Marc J. Nieuwenhuijse, MD, PhD from the Patient Centered Comparative Effectiveness Program and US Food and Drug Administration Medical Device Epidemiology Science and Infrastructure Center, Department of Public Health, Weill Cornell Medical College, New York, City; the Department of Orthopaedics, Leiden University Medical Center, the Netherlands; and the Office of Surveillance and Biometrics, Center for Devices and Radiological Health, US Food and Drug Administration, Silver Spring, MD and colleagues.