Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, China; Department of Orthopedic Surgery, Third Military Medical University Southwest Hospital, Chongqing, China.
Department of Orthopedic Surgery, West China Hospital, Sichuan University, Chengdu, China.
World Neurosurg. 2022 Oct;166:e484-e494. doi: 10.1016/j.wneu.2022.07.033. Epub 2022 Jul 16.
Due to the lack of an additional anterior plate, the motion stability of a zero-profile device with an anchored cage (AC) may be inferior to that of a traditional plate-cage construct (PCC). However, the impact of this difference in motion stability on various outcomes has not been fully explored. Therefore, the aim of this study was to compare the motion stabilization features of an AC and a PCC and analyze their impact on postoperative outcomes and complications.
A retrospective study of patients treated with single-level anterior cervical discectomy and fusion from January 2008 to May 2016 was performed. First, clinical and radiological outcomes, postoperative complications and time to achieve motion stabilization were compared between the AC and PCC groups. Then, based on the time to achieve motion stabilization, all patients were divided into group A (time to achieve motion stabilization <3 months), group B (time to achieve motion stabilization from 3-6 months), and group C (time to achieve motion stabilization >6 months). The early postoperative complications were compared across the 3 groups. Motion stabilization was measured on dynamic cervical radiographs using the interspinous process method and Cobb angle method according to previously published methods.
A total of 160 patients met the inclusion criteria, including 90 patients in the AC group and 70 patients in the PCC group. There were no significant differences between the AC and PCC groups in the clinical outcomes, C2-7 angle change, segmental angle change, final fusion rate or adjacent-level degeneration (P > 0.05). The disc height loss was 2.26 ± 1.00 mm in the AC group and 1.76 ± 1.13 mm in the PCC group (P = 0.004), and the incidence of implant subsidence was 24.44% in the AC group and 11.43% in the PCC group (P = 0.036). In addition, the PCC was more dynamically stable than the AC at 3 months post-surgery (P < 0.001), and at this time, the disc height loss and implant subsidence in motion-stable patients were significantly lower than those in motion-unstable patients (P < 0.05). Furthermore, our results also showed that when the arrival time of motion stabilization was prolonged, the loss of disc height and occurrence of subsidence gradually increased.
More attention should be given to minimizing the adverse impact of poor motion stability in the design and development of future zero-profile cervical implants, although this has little impact on clinical efficacy.
由于缺乏额外的前板，带锚定笼的零切迹装置（AC）的运动稳定性可能不如传统的板笼结构（PCC）。然而，这种运动稳定性差异对各种结果的影响尚未得到充分探讨。因此，本研究旨在比较 AC 和 PCC 的运动稳定特性，并分析其对术后结果和并发症的影响。
回顾性分析 2008 年 1 月至 2016 年 5 月行单节段前路颈椎间盘切除融合术的患者。首先，比较 AC 组和 PCC 组的临床和影像学结果、术后并发症和达到运动稳定的时间。然后，根据达到运动稳定的时间，将所有患者分为 A 组（达到运动稳定的时间<3 个月）、B 组（达到运动稳定的时间为 3-6 个月）和 C 组（达到运动稳定的时间>6 个月）。比较 3 组患者的早期术后并发症。采用棘突间法和 Cobb 角法，根据既往发表的方法，在颈椎动力位片上测量运动稳定性。
共有 160 例患者符合纳入标准，其中 AC 组 90 例，PCC 组 70 例。AC 组和 PCC 组在临床结果、C2-7 角变化、节段角变化、最终融合率或邻近节段退变方面无统计学差异（P>0.05）。AC 组的椎间盘高度丢失为 2.26±1.00mm，PCC 组为 1.76±1.13mm（P=0.004），AC 组的植入物下沉发生率为 24.44%，PCC 组为 11.43%（P=0.036）。此外，术后 3 个月时，PCC 比 AC 更具动态稳定性（P<0.001），此时运动稳定患者的椎间盘高度丢失和植入物下沉明显低于运动不稳定患者（P<0.05）。此外，我们的结果还表明，随着运动稳定到达时间的延长，椎间盘高度丢失和下沉的发生率逐渐增加。
在未来零切迹颈椎植入物的设计和开发中，应更加关注最小化运动稳定性不良的不良影响，尽管这对临床疗效影响不大。
