Department of Orthopedics and Traumatology, University Medical Center Mannheim, Mannheim, Germany.
Spine (Phila Pa 1976). 2010 Oct 15;35(22):E1167-71. doi: 10.1097/BRS.0b013e3181e6bc59.
A total of 12 human cervical spines were tested in vitro in a biomechanical nondestructive set-up to compare the primary stability of different posterior cervical instrumentations after a bilevel corpectomy.
To evaluate the primary 3-dimensional stability with special focus on the impact of cervical pedicle screws.
Cervical pedicle screw fixation gains popularity due to supposed higher stability. However, biomechanical studies are rare. Especially the impact of a combination of lateral mass and pedicle screws on stability in multilevel posterior stabilizations has not been evaluated until now.
A total of 12 human cervical specimens were loaded with pure moments and unconstrained motion between C4 and C7 was measured. The specimen were tested in the intact state, all lateral mass screws (all LMS) from C4-C7, cervical pedicle screws (CPS) C4 and C7 left, LMS C4-C7 right, C5+C6 left, CPS C4+C7 bilateral, LMS C5+C6, and a anterior-posterior instrumentation (360°).
All instrumentations showed a higher stability compared with the intact state. No difference was found for uni- or bilateral applied CPS. The all LMS showed comparable stability than the CPS instrumentations.
From a biomechanical primary stability point it seems unnecessary to add CPS in a bilevel corpectomy model. If CPS are added, the unilateral application seems sufficient.
在生物力学非破坏性设置中，总共对 12 个人类颈椎进行了体外测试，以比较双节段椎体切除术后不同颈椎后固定器械的初始稳定性。
评估三维初始稳定性，特别关注颈椎椎弓根螺钉的影响。
由于假定具有更高的稳定性，颈椎椎弓根螺钉固定术越来越受欢迎。但是，生物力学研究很少。特别是，直到现在，还没有评估侧块螺钉和椎弓根螺钉的组合对多节段后路稳定的影响。
总共对 12 个人类颈椎标本进行纯力矩加载，并测量 C4 和 C7 之间的无约束运动。标本在完整状态、C4-C7 所有侧块螺钉（所有 LMS）、C4 和 C7 左侧颈椎椎弓根螺钉（CPS）、LMS C4-C7 右侧、C5+C6 左侧、C4+C7 双侧、LMS C5+C6 和前后向固定（360°）下进行测试。
与完整状态相比，所有固定器械均显示出更高的稳定性。单侧或双侧应用 CPS 之间没有差异。所有 LMS 的稳定性与 CPS 固定装置相当。
从生物力学初始稳定性的角度来看，在双节段椎体切除模型中添加 CPS 似乎没有必要。如果添加 CPS，则单侧应用似乎就足够了。
