Combining All Available Clinical Outcomes on Cervical Disc Arthroplasty: A Systematic Review and Meta-Analysis

Abstract

Background: Reviews of total disc arthroplasty (TDA) performance have focused on prospective randomized controlled trials (RCTs), excluding potentially important clinical information reported by others. The goal of the present study was to perform a comprehensive review, including both RCTs and non-randomized cohorts with more than five years of clinical outcome. We further explored the differences in outcome between prospective RCT and non-randomized, including retrospective studies. Methods: A systematic literature review was performed following PRISMA guidelines. Inclusion criteria were: clinical follow-up ≥ 5 years with quantitative clinical and radiographic outcome. All studies that met these criteria, including retrospective and non-randomized studies, were included, for a total of 62 studies. As anterior cervical discectomies and fusion (ACDF) was included as a control group in the majority of the studies, comparisons between TDA and ACDF were conducted. Results: Overall, there was a statistically significant difference between the rates of secondary surgeries reported for prospective RCTs and all other studies, with reoperation rates of 5.4% for prospective RCT studies v. 7.5% in all others (P<0.01). Including all studies, the reoperation rate for TDA patients was 5.6% and for fusion patients (included as control groups), 7.8%, (P=0.06). Overall, the reported incidence of adjacent segment degeneration was 26.2% in TDA patients and 43.9% in fusion patients (P<0.001). Conclusions: These findings demonstrated the need for including all available data to assess the current outcomes of cervical disc arthroplasty and account for potential biases.

An additively manufactured model for preclinical testing of cervical devices

“…Cervical disc replacements (CDRs) were designed with the intention to restore natural kinematics to patients that would typically undergo fusion surgery 1–5 . This patient population is relatively young, with an average age of 45.2 ± 5.2 years at the time of surgery, indicating that ideally, these devices should survive beyond 30 years 6,7 . While numerous CDR designs have been introduced over the past two decades, the majority have since been withdrawn from the market due to a failure to meet clinical expectation, with high complication rates such as adjacent segment degeneration, heterotopic ossification, and mechanical failures associated with potential revision surgeries 8–11 .…”

“… 1 , 2 , 3 , 4 , 5 This patient population is relatively young, with an average age of 45.2 ± 5.2 years at the time of surgery, indicating that ideally, these devices should survive beyond 30 years. 6 , 7 While numerous CDR designs have been introduced over the past two decades, the majority have since been withdrawn from the market due to a failure to meet clinical expectation, with high complication rates such as adjacent segment degeneration, heterotopic ossification, and mechanical failures associated with potential revision surgeries. 8 , 9 , 10 , 11 Specifically, many devices have migrated within the vertebral bodies or loosened.…”