Study Suggests there May be No Benefit to Using Newer Joint Replacement SystemsSep 16, 2014
There may be no clinical benefit to using newer joint replacement systems compared to older ones serving the same function, according to a systematic review published online September 9th in the BMJ. In some of the systems, the rate of failure in the newer was higher compared to the traditional counterpart.
Five joint replacement devices were selected for the review: ceramic-on-ceramic bearings, modular femoral necks, uncemented monoblock cups, high flexion knee replacement and gender specific knee replacement. Researchers chose these devices based on three criteria: there must be a rationale behind their supposed superiority, they must have a 90 percent reported completed in a national orthopedic registry and they must be comparable to a traditional device used for the same purpose.
The researchers analyzed 118 studies involving a total of 15,384 implants in 13,164 patients for their review. They found no evidence of clinical improvement in 4 out of 5 devices and the evidence was lacking for the fifth device, modular femoral necks. There was a higher rate of revision compared to traditional counterparts with the ceramic-on-ceramic bearings, modular femoral necks and high flexion knee replacement. In modular femoral neck replacements, the revision rate was nearly doubled with a hazard rate of 1.92. 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 revision rate was comparable for uncemented monoblock hip replacements and sex-specific knee replacements. Based on the findings, the authors believe here should be greater oversight to clear changes 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.
The authors did not include metal-on-metal hip replacements in their review. Last year, the U.S. Food and Drug Administration (FDA) issued cautionary guidelines stating that the rate of revision surgery is higher with all-metal hip devices. The agency also stated that metal-on-metal hip implants have a risk of releasing metal debris into the bloodstream and nearby tissues when the surfaces of the implant rub together.