Açikbaş S C, Arslan F Y, Tuncer M R
Akdeniz Universitesi Tip Fakültesi Hastanesi, Beyin ve Sinir Cerrahisi, Dumlupinar Bulvari, Kampus, Antalya, Turkey.
Acta Neurochir (Wien). 2003 Nov;145(11):949-54; discussion 954-5. doi: 10.1007/s00701-003-0116-0.
In this article the authors investigated the consequences of misplaced thoracolumbar pedicle screws on late spinal stability.
This study consisted of 16 patients with screws in the proper position (Group A) and a further 16 patients with screw misplacement (Group B) who had previously undergone transpedicular screw fixation following thoracolumbar injury. The authors retrospectively evaluated the bone fusion, anterior height of the fractured vertebrae and the kyphotic deformity on postoperative early neutral, and on postoperative long-term neutral and dynamic radiographs in both groups. The results and in addition a back pain questionnaire were compared within each group, and also between groups A and B.
The decreased anterior height of the fractured vertebrae and the increased degree of kyphosis on postoperative early radiographs in group B demonstrated that the correction of the deformity was inadequate in patients with screw misplacement. Furthermore, an additional increase in the degree of kyphosis on long-term neutral radiographs indicated a significant progression in late kyphotic deformity in group B, whereas it was not seen in group A. The evidence of significant motion on neutral-flexion and flexion-extension long-term radiographs demonstrated impaired stability in group B, whilst it was only evident in neutral-flexion radiographs in group A. Moreover, moderate to severe back pain was commonly reported by patients in group B and correlated with lack of bony fusion and significant motion.
The authors conclude that the screw misplacement decreased the original spinal stability provided by the instrumentation. Therefore, correct placement of pedicle screws is required to maintain long-term spinal stability.
在本文中，作者研究了胸腰椎椎弓根螺钉位置不当对后期脊柱稳定性的影响。
本研究包括16例螺钉位置正确的患者（A组）和另外16例螺钉位置不当的患者（B组），这些患者之前均因胸腰椎损伤接受了椎弓根螺钉固定术。作者回顾性评估了两组患者术后早期中立位、术后长期中立位及动态X线片上的骨融合情况、骨折椎体的前缘高度和后凸畸形情况。对每组内以及A组和B组之间的结果及一份背痛问卷进行了比较。
B组术后早期X线片上骨折椎体前缘高度降低及后凸程度增加，表明螺钉位置不当的患者畸形矫正不足。此外，长期中立位X线片上后凸程度进一步增加，表明B组后期后凸畸形有显著进展，而A组未出现这种情况。长期中立位-前屈和屈伸位X线片上有明显活动的证据表明B组稳定性受损，而A组仅在中立位-前屈X线片上有明显活动。此外，B组患者普遍报告有中度至重度背痛，且与骨不融合及明显活动相关。
作者得出结论，螺钉位置不当降低了器械所提供的原始脊柱稳定性。因此，需要正确放置椎弓根螺钉以维持长期脊柱稳定性。
