Guyer Richard D, Coric Domagoj, Nunley Pierce D, Ohnmeiss Donna D
Center for Disk Replacement at Texas Back Institute, Plano, TX.
Carolina Neurosurgery and Spine Associates, Charlotte, NC.
Clin Spine Surg. 2022 May 1;35(4):166-169. doi: 10.1097/BSD.0000000000001314. Epub 2022 Mar 29.
This study was a post hoc analysis of data collected from 2 Food and Drug Administration (FDA) Investigational Device Exemption (IDE) trials.
The purposes of this study were to: (1) measure disk space heights adjacent to the level to be treated with a total disk replacement (TDR); (2) analyze cervical disk space heights to be replaced with TDR; and (3) investigate the frequency of use of a smaller height TDR when available.
Cervical TDR produces outcomes noninferior or superior to anterior cervical discectomy and fusion. While the restoration of the height of a collapsed, degenerated disk is a surgical goal, there are potential problems with overdistracting the segment with an implant.
Disk heights were measured using radiographs from the 1-level Simplify Cervical Artificial Disk IDE trial, producing values for 259 levels adjacent to the treated level and 162 treated levels. The device is available in 4, 5, and 6 mm heights. The 4 mm height became available only after treatment was 13% complete in the single-level trial and was available for all of the 2-level trial.
Measurements of 259 adjacent levels found that 55.2% of disk spaces had a height of <4 mm. Among operated levels, 82.7% were <4 mm. When a 4 mm TDR was available, it was used in 38.4% of operated levels in the 1-level trial and 54.3% of levels in the 2-level trial.
Among nonoperated levels, 55.2% were of height <4 mm, suggesting that TDRs of greater heights may potentially overdistract the disk space. The 4 mm TDR was selected by surgeons in 49.4% of all implanted levels, suggesting a preference for smaller TDR height. Further investigation is warranted to determine if the lower height implants are related to clinical and/or radiographic outcomes.
Level III.
本研究是对从两项美国食品药品监督管理局（FDA）的医疗器械研究豁免（IDE）试验中收集的数据进行的事后分析。
本研究的目的是：（1）测量与拟行全椎间盘置换（TDR）治疗节段相邻的椎间盘间隙高度；（2）分析拟用TDR置换的颈椎间盘间隙高度；（3）调查在有较小高度TDR可用时其使用频率。
颈椎TDR产生的结果不劣于或优于颈椎前路椎间盘切除融合术。虽然恢复塌陷、退变椎间盘的高度是手术目标，但使用植入物过度撑开节段存在潜在问题。
使用来自单节段Simplify颈椎人工椎间盘IDE试验的X线片测量椎间盘高度，得出259个与治疗节段相邻节段以及162个治疗节段的测量值。该器械有4毫米、5毫米和6毫米三种高度。4毫米高度的器械在单节段试验治疗完成13%后才可用，并且在所有双节段试验中均有。
对259个相邻节段的测量发现，55.2%的椎间盘间隙高度小于4毫米。在手术节段中，82.7%小于4毫米。当有4毫米TDR可用时，在单节段试验中，38.4%的手术节段使用了它，在双节段试验中，54.3%的节段使用了它。
在未手术节段中，55.2%的节段高度小于4毫米，这表明更高高度的TDR可能会过度撑开椎间盘间隙。在所有植入节段中，外科医生选择4毫米TDR的比例为49.4%，这表明他们更倾向于较小高度的TDR。有必要进一步研究以确定较低高度的植入物是否与临床和/或影像学结果相关。
三级。
