Margulies J Y, Casar R S, Caruso S A, Neuwirth M G, Haher T R
Spine Service Department of Orthopedic Surgery, Montefiore Medical Center, Bronx, New York 10467, USA.
Eur Spine J. 1997;6(4):245-8. doi: 10.1007/BF01322446.
Biomechanical studies have shown hooks to be superior to pedicle screws in pull-out, especially in osteoporosis. This study evaluates the possible increase in stiffness of pedicle screws provided by laminar hooks while applying non-destructive forces to a vertebrectomy model assembled with Compact Cotrel Dubousset (CCD) instrumentation. Synthetic vertebrae were employed in a three-level vertebrectomy model. CCD screw-based three-level constructs with and without sublaminar hooks in the caudal element were tested in flexion, extension, compression, lateral bending, and torsion. There was no statistically significant advantage in adding inferior laminar hooks to a caudal end vertebra that had bilateral pedicle screws in any of the testing modes. Torsional stability, however, was augmented, but not significantly. Torsional instability and osteoporotic bone may be the clinical justifications for adding laminar hooks below screws in the caudal end vertebra.
生物力学研究表明，在拔出力方面，尤其是在骨质疏松症患者中，钩优于椎弓根螺钉。本研究评估了在对使用紧凑型 Cotrel Dubousset（CCD）器械组装的椎体切除模型施加无损力时，椎板钩对椎弓根螺钉刚度可能的增加情况。在三级椎体切除模型中使用了合成椎体。对基于 CCD 螺钉的三级结构进行测试，在尾侧单元中分别有和没有椎板下钩，测试其在屈曲、伸展、压缩、侧弯和扭转时的情况。在任何测试模式下，对于已经有双侧椎弓根螺钉的尾端椎体，添加下椎板钩并没有统计学上的显著优势。然而，扭转稳定性有所增强，但不显著。扭转不稳定性和骨质疏松性骨可能是在尾端椎体的螺钉下方添加椎板钩的临床依据。
