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EDITORIAL PERSPECTIVE
The controversy surrounding the role and actual function of so-called „dynamic“ fixation devices was reflected in the reviewers' comments. The devices in question are different from one another and defy simple biomechanical categorization. Their ability to provide long-term stabilization of a damaged operated-on segment remains to be seen – toggle loosening, implant breakage, foreign body reactions all await further clarification.
The other question that remains unanswered: Are patients with dynamic stabilization devices still mobile in their target level, or did they in fact inadvertently fuse? As more of these devices push on the market, a comparative biomechanical analysis using variety of loading mechanisms, including load to failure and fatigue loading together with monitoring of adjacent segment disc mechanics would appear to be a helpful first step to allow clinicians to understand the effects of the devices that are being offered for implantation. Again, at this time the basic first step, indications remain unclear. Then, the same can be said for the phenomenon of ‘adjacent disc disease.’ Is it patient borne, surgeon created, or a mixture of both? It is this first step that we need to understand before we can move ahead and try to identify preventative variables.
