In light of the failure of articular surface replacement and large head size metal-on-metal joint replacement devices, scientists, doctors, and health policy professionals have highlighted the need for a more thorough and evidence-based introduction of joint replacement devices and for the development of an infrastructure for timely evaluation of these devices.
In a recently published study in the BMJ, a group of researchers, led by Dr. Marc J. Nieuwenhuijse, systematically evaluated the evidence concerning the introduction of five innovative, relatively recent, and already widely implemented devices used in total joint replacement. The research team evaluated comparative data from clinical trials, observational studies, and large national arthroplasty registries to study effectiveness and safety of the new devices versus existing, well proven, comparable devices. The five technologies reviewed are ceramic-on-ceramic bearings, modular femoral necks, and uncemented monoblock (not metal-on-metal) acetabular cups in total hip replacement, and high flexion implants and gender-specific implants in total knee replacement.
After assessing 10,557 search hits, 118 studies (94 unique study cohorts) met the criteria for inclusion. The data related to 15,384 implants in 13,164 patients. None of the five device innovations was found to improve functional or patient reported outcomes, according to the article’s abstract. National registries reported two- to 12-year follow-up for revision occurrence related to more than 200,000 implants. Reported comparative data with well established alternative devices (over 1,200,000 implants) did not show improved device survival. Moreover, the researchers found higher revision occurrence associated with modular femoral necks (hazard ratio 1.9) and ceramic-on-ceramic bearings (hazard ratio 1.0-1.6) in hip replacement and with high flexion knee implants (hazard ratio 1.0-1.8), according to the BMJ.
The researchers wrote that theydid not find convincing high quality evidence supporting the use of five newer devices. Moreover, the data showed that existing devices may be safer to use in total hip or knee replacement. The authors call for improved regulation and professional society oversight “to prevent patients from being further exposed to these and future innovations introduced without proper evidence of improved clinical efficacy and safety,” according to the BMJ.