Spivak Jeffrey M, Zigler Jack E, Philipp Travis, Janssen Michael, Darden Bruce, Radcliff Kris
NYU Langone Orthopedic Hospital, New York, NY, USA.
Texas Back Institute, Plano, TX, USA.
Int J Spine Surg. 2022 Feb;16(1):186-193. doi: 10.14444/8187. Epub 2022 Feb 17.
Cervical artificial disc replacement (C-ADR) has become a common and accepted surgical treatment for many patients with cervical disc degeneration/herniation and radiculopathy who have failed nonoperative treatment. Midterm follow-up studies of the original investigational device exemption trials comparing C-ADR to traditional anterior cervical discectomy and fusion (ACDF) have revealed C-ADR patients have less adjacent-level disease and fewer reoperations at 5 to 7 years. The purpose of this study was to examine the relationship of radiographic adjacent-level disease (R-ALD) with the amount of index-level segmental range of motion (ROM) in C-ADR patients using the long-term follow-up data from the ProDisc-C investigational device exemption trial.
This was a post hoc analysis of a 1:1 randomized controlled trial. The initial previously described Food and Drug Administration-approved 2-year study was extended, and consenting patients in the original study were followed at annual intervals up to 7 years. Logistic regression was used to assess any progression in adjacent-level disease (ALD). Ordinal logistic regression was also used to assess the relationship between any progressive R-ALD and final flexion extension (F/E) ROM in C-ADR patients. Spearman's rank-order correlation was used when R-ALD was kept as an ordinal variable to assess the same relationship.
At the last follow-up visit, the rate of progressive R-ALD was significantly higher in ACDF patients than in C-ADR patients. When C-ADR patients were divided into 3 groups based on final F/E ROM, those with 0° to 3° ( = 19), 4° to 6° ( = 15), and 7° ( = 42) of segmental motion at the index procedure level, the rate of progressive R-ALD trended significantly with final ROM ( = 0.01).
C-ADR leads to a significant decrease in R-ALD compared to ACDF. The difference in R-ALD is related to the preservation of motion at the index level and resultant preservation of kinematics and forces across the adjacent disc space.
颈椎人工椎间盘置换术（C-ADR）已成为许多非手术治疗失败的颈椎间盘退变/突出伴神经根病患者常用且被认可的手术治疗方法。对最初的研究性器械豁免试验进行中期随访研究，将C-ADR与传统前路颈椎间盘切除融合术（ACDF）进行比较，结果显示C-ADR患者在5至7年时相邻节段疾病较少，再次手术的次数也较少。本研究的目的是利用ProDisc-C研究性器械豁免试验的长期随访数据，研究颈椎人工椎间盘置换术（C-ADR）患者中影像学相邻节段疾病（R-ALD）与责任节段活动度（ROM）的关系。
这是一项对1:1随机对照试验的事后分析。最初经美国食品药品监督管理局批准的为期2年的研究进行了延长，对原研究中同意参与的患者每年进行随访，直至7年。采用逻辑回归评估相邻节段疾病（ALD）的任何进展情况。还采用有序逻辑回归评估C-ADR患者中任何进展性R-ALD与最终屈伸（F/E）活动度之间的关系。当将R-ALD作为有序变量时，采用Spearman等级相关来评估相同的关系。
在最后一次随访时，ACDF患者进展性R-ALD的发生率显著高于C-ADR患者。当根据最终F/E活动度将C-ADR患者分为3组时，在责任节段手术水平节段活动度为0°至3°（ = 19）、4°至6°（ = 15）和7°（ = 42）的患者中，进展性R-ALD的发生率与最终活动度显著相关（ = 0.01）。
与ACDF相比，C-ADR可显著降低R-ALD。R-ALD的差异与责任节段活动度的保留以及相邻椎间盘间隙运动学和力的保留有关。
