UPS固定对TILF术后邻近节段生物力学影响的有限元分析

分析单侧椎弓根螺钉(UPS)固定对经椎间孔入路腰椎椎间融合术(TLIF)椎间融合前/后邻近节段生物力学的影响,评价UPS技术的安全性和有效性。通过建立TLIF三维有限元模型,分析UPS与双侧椎弓根螺钉(BPS)在TLIF椎间融合前/后对模型整体位移、邻近椎间盘和小关节应力应变、椎间融合器和椎弓根螺钉应力的影响。其结果显示UPS和BPS之间,两者的模型整体位移、邻近小关节和椎间盘应力应变差异不大,但UPS的椎间融合器和椎弓根螺钉应力明显较高,并且其椎间融合后椎间融合器应力较融合前明显增加。该研究证实了UPS应用于TILF时具有较好的生物力学稳定性,但相较于BPS并不会减缓邻近节段退变,反而会增加内植物相关并发症的风险。

Finite element analysis of biomechanical effects of unilateral pedicle screw fixation on adjacent segments after transforaminal lumbar interbody fusion

To analyze the effect of Unilateral Pedicle Screw Fixation (UPS) on the biomechanics of adjacent segments before and after transforaminal lumbar interbody fusion (TLIF) interbody fusion, and to evaluate the safety and effectiveness of UPS. By establishing a three-dimensional finite element model of TLIF, the effects of UPS and Bilateral Pedicle Screw (BPS) on the overall displacement of the model, stress- strain of adjacent discs and facets, stress of intervertebral fusion cage and pedicle screw before and after TLIF interbody fusion were analyzed. The results showed that there was no significant difference between UPS and BPS in overall displacement, stress-strain of adjacent facet joints and intervertebral discs, but the stress of UPS interbody fusion cage and pedicle screw was significantly higher, and the stress of UPS interbody fusion cage was significantly higher than that before fusion. This study confirmed that UPS has good biomechanical stability when applied to TILF, but compared with BPS, UPS does not slow down the degeneration of adjacent segments, on the contrary, it increases the risk of internal plant-related complications.