Cervical artificial disc replacement (C-ADR) is not a new technology but one that has seen many technological advances in the past 10 years. Indeed, a recent review described total disc arthroplasty as the most innovative development in the history of spinal surgery. The primary goals of C-ADR are to reduce or eliminate pain, and restore normal segmental motion. The aim of this analysis was to identify, extract and examine key health outcomes and economic data from published health technology assessment (HTA) reports on C-ADR, with the aim of understanding how the evolution of this technology has influenced assessments internationally.

A comprehensive search of over 90 HTA organization websites and the INAHTA HTA database using key terms for C-ADR surgical procedures was coupled with a literature search of recent systematic reviews. No language restrictions were applied.

Twenty HTA reports of C-ADR surgery published from 2005 to 2022 were included for review. Several HTAs (4/20) were updates or reassessments by the same agency and one was an update across agencies (Italy update of Belgian HTA). While many of the HTAs concluded C-ADR is as effective as standard care and superior in certain outcomes, there was no pattern or consistency in the conclusions or recommendations from these assessments, even as the evidence base expanded over time. Our analysis found this was largely due to variations in HTA approaches among agencies including: differences in research questions asked, PICO (Population, Intervention, Comparator, Outcomes) criteria and methods performed, such as: rapid versus full systematic reviews; inclusion of economic evaluations and/or budget impact analyses.

Indeed, one of the only predictive factors for a positive HTA was a favorable cost-effectiveness analysis.

C-ADR is an established technology with extensive HTA investigation internationally. The lack of a consistent approach taken by HTA bodies made prediction of successful HTA outcomes difficult. Future alignment of key evaluation processes and methods may help address current international variations and support consistent decision making on patient access.