Arthroplasty in cervical degenerative disc disease: fulfilling its long-term promise?

There has been an increasing interest in anterior cervical discectomy with arthroplasty (ACDA) over the past decade. The presumed benefit of ACDA over the more common anterior cervical discectomy with fusion (ACDF) approach is reducing rates of adjacent segment disease, by maintaining mobility in the operated motion segment. Several authors have questioned the role of arthroplasty in actually preventing adjacent segment disease (1,2). In a recent meta-analysis, the authors found a 5.1% incidence of adjacent segment disease 12–24 months after ACDA (3). This is roughly consistent with the yearly incidence of adjacent segment disease after ACDF, which has been reported to be 2.9% (4). If there is indeed a lower yearly incidence of adjacent segment disease in ACDA compared to ACDF, this should become increasingly apparent over time.