Wu Jie, Shi Lei, Liu Daohong, Wu Zhigang, Gao Peng, Liu Wenwen, Li Xiaokang, Guo Zheng
540274Department of Orthopedics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shanxi, China.
Department of Orthopaedics, 12509the 8th Medical Center of Chinese PLA General Hospital, Beijing, China.
Global Spine J. 2023 Mar;13(2):393-399. doi: 10.1177/2192568221996692. Epub 2021 Mar 4.
Animal experiment.
To evaluate whether the use of polyetheretherketone (PEEK) rods for posterior spinal fixation can improve screw stability.
Sheep models of anterior-posterior cervical fusion were used in this study. Six sheep were randomly assigned to the PEEK rod group and titanium alloy group. A total of 8 screws and 2 fixing rods were implanted in each sheep. At 24 weeks postoperatively, a computed tomography (CT) evaluation, pull-out test, micro-CT evaluation and histological evaluation were conducted to evaluate screw stability in the harvested surgical segments.
According to the CT evaluation, there were no signs of screw loosening in either group. The pull-out force and energy of the PEEK rod group were significantly higher than those of the titanium alloy rod group. Denser and thicker trabecular bone around the screw was observed in the PEEK rod group according to the micro-CT reconstructed images, and quantitative analysis of the micro-CT data confirmed this finding. In the histological evaluation, more abundant and denser bone trabeculae were also observed in the PEEK rod group. However, there was no significant difference in the bone-screw interface between the 2 groups.
Posterior spinal fixation with PEEK rods can increase screw stability by promoting bone growth around the screw but cannot promote bone integration at the bone-screw interface in an animal model study. This finding presents a new idea for clinical practices to reduce screw loosening rate.
动物实验。
评估使用聚醚醚酮（PEEK）棒进行后路脊柱固定是否能提高螺钉稳定性。
本研究采用前后路颈椎融合的绵羊模型。将6只绵羊随机分为PEEK棒组和钛合金组。每只绵羊植入8枚螺钉和2根固定棒。术后24周，进行计算机断层扫描（CT）评估、拔出试验、显微CT评估和组织学评估，以评估所采集手术节段的螺钉稳定性。
根据CT评估，两组均无螺钉松动迹象。PEEK棒组的拔出力和能量显著高于钛合金棒组。根据显微CT重建图像，PEEK棒组螺钉周围的小梁骨更致密、更厚，显微CT数据的定量分析证实了这一发现。在组织学评估中，PEEK棒组也观察到更丰富、更致密的骨小梁。然而，两组之间的骨-螺钉界面无显著差异。
在动物模型研究中，使用PEEK棒进行后路脊柱固定可通过促进螺钉周围的骨生长来提高螺钉稳定性，但不能促进骨-螺钉界面的骨整合。这一发现为临床实践降低螺钉松动率提供了新思路。
