Adjacent segment degeneration or disease after cervical total disc replacement: a meta-analysis of randomized controlled trials

Shuai Xu,Zhenqi Zhu,Yalong Qian,Yan Liang,Haiying Liu

doi:10.1186/s13018-018-0940-9

Abstract

BackgroundAnterior cervical discectomy and fusion (ACDF) has been widely used in cervical spondylosis, but adjacent segment degeneration/disease (ASD) was inevitable. Cervical total disc replacement (TDR) could reduce the stress of adjacent segments and retard ASD in theory, but the superiority has not been determined yet. This analysis aimed that whether TDR was superior to ACDF for decreasing adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis).MethodsA meta-analysis was performed according to the guidelines of the Cochrane Collaboration with PubMed, EMBASE, Cochrane Library and CBM (China Biological Medicine) databases. It included randomized controlled trials (RCTs) that reported ASDeg, ASDis, and reoperation on adjacent segments after TDR and ACDF. Two investigators independently selected trials, assessed methodological quality, and evaluated the quality of this meta-analysis using the grades of recommendation, assessment, development, and evaluation (GRADE) approach.ResultsEleven studies with 2632 patients were included in the meta-analysis. The overall rate of ASD in TDR group was lower than ACDF group (OR = 0.6; 95% CI [0.38, 0.73]; P < 0.00001). Both the incidence of ASDeg and the reoperation rate were statistically lower in the TDR group than in the ACDF group (OR = 0.58, P < 0.00001; OR = 0.52, P = 0.01, respectively). Subgroup analysis was performed according to the follow-up time and trial site; the rate of ASDeg was lower in patients underwent TDR no matter the follow-up time, and TDR tended to increase the superiority across time. The rate of ASDeg was also lower with TDR both in the USA and China (P < 0.0001, P = 0.03, respectively). But the cost-effectiveness result might be prone to neither of the two surgery approaches. According to GRADE, the overall quality of this meta-analysis was moderate.ConclusionsTDR decreased the rates of ASDeg and reoperation compared with that of ACDF, and the superiority may become more apparent over time. We cautiously and slightly suggest adopting TDR according to the GRADE but may not believe it excessively.

Highlights

Anterior cervical discectomy and fusion (ACDF) is widely performed for the treatment of cervical diseases, estimated to provide relief for more than 90% of radicular and myelopathic complaints [1]
adjacent segment degeneration (ASDeg) was defined as radiographic changes at the adjacent segments, whereas adjacent segment disease (ASDis) was used to refer to the development of new clinical symptoms, such as mechanical neck pain or coronal-sagittal imbalance
The etiology and symptomatology of these adjacent segment changes have remained intensely controversial. Some experts believe it is the natural progress of cervical disc disease [6–8], while others insist fusion can change the biomechanics of adjacent segments, accelerating adjacent segment degeneration/disease (ASD) [2, 9]

Summary

Introduction

Anterior cervical discectomy and fusion (ACDF) is widely performed for the treatment of cervical diseases, estimated to provide relief for more than 90% of radicular and myelopathic complaints [1]. The etiology and symptomatology of these adjacent segment changes have remained intensely controversial Some experts believe it is the natural progress of cervical disc disease [6–8], while others insist fusion can change the biomechanics of adjacent segments, accelerating adjacent segment degeneration/disease (ASD) [2, 9]. Anterior cervical discectomy and fusion (ACDF) has been widely used in cervical spondylosis, but adjacent segment degeneration/disease (ASD) was inevitable. Cervical total disc replacement (TDR) could reduce the stress of adjacent segments and retard ASD in theory, but the superiority has not been determined yet. This analysis aimed that whether TDR was superior to ACDF for decreasing adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis)

Methods

Results

Conclusion