Veterinary and Comparative Orthopaedics and Traumatology ( IF 1.3 ) Pub Date : 2021-04-15 , DOI: 10.1055/s-0041-1725016 Claudia Zindl 1 , Noel Fitzpatrick 2 , Alan S Litsky 3 , Matthew J Allen 1
Objective The aim of this study was to determine the biomechanical behaviour of a novel distraction–fusion system, consisting of an intervertebral distraction screw, pedicle locking screws and connecting rods, in the canine caudal cervical spine.
Study Design Biomechanical study in cadaveric canine cervicothoracic (C3–T3) spines (n = 6). Cadaveric spines were harvested, stripped of musculature, mounted on a four-point bending jig, and tested using non-destructive four-point bending loads in extension (0–100 N), flexion (0–60 N) and lateral bending (0–40 N). Angular displacement was recorded from reflective optical trackers rigidly secured to C5, C6 and C7. Data for primary and coupled motions were collected from intact spines and following surgical stabilization (after ventral annulotomy and nucleotomy) with the new implant system.
Results As compared with the intact spine, instrumentation significantly reduced motion at the operated level (C5-C6) with a concomitant non-significant increase at the adjacent level (C6-C7).
Conclusion The combination of a locking pedicle screw-rod system and intervertebral spacer provides an alternative solution for surgical distraction–stabilization in the canine caudal cervical spine and supports the feasibility of using this new implant system in the management of disc-associated cervical spondylomyelopathy in dogs. The increase in motion at C6-C7 may suggest the potential for adjacent level effects and clinical trials should be designed to address this.
中文翻译:
一种新型犬颈椎融合系统的运动学
目的 本研究的目的是确定由椎间牵引螺钉、椎弓根锁定螺钉和连杆组成的新型牵引-融合系统在犬颈椎尾部的生物力学行为。
研究设计 尸体犬颈胸椎 (C3–T3) 刺 ( n = 6) 的生物力学研究。采集尸体棘,剥去肌肉组织,安装在四点弯曲夹具上,并在伸展(0-100 N)、屈曲(0-60 N)和横向弯曲(0 –40 牛顿)。角位移是从刚性固定在 C5、C6 和 C7 上的反射光学跟踪器记录的。主要和耦合运动的数据是从完整的脊柱中收集的,并在使用新的植入系统进行手术稳定后(在腹侧瓣环切开术和核切开术之后)。
结果 与完整脊柱相比,内固定术显着减少了手术节段 (C5-C6) 的运动,同时相邻节段 (C6-C7) 的运动不显着增加。
结论 锁定椎弓根螺钉系统和椎间垫片的组合为犬颈椎尾椎的手术牵引-稳定提供了一种替代解决方案,并支持使用这种新植入系统治疗犬椎间盘相关性颈椎病的可行性. C6-C7 运动的增加可能表明存在相邻水平效应的可能性,应设计临床试验来解决这个问题。