METHODS: This is a retrospective study involving prospectively enrolled patients. A total of 119 patients with 174 segments undergoing OLIF procedure were included and analyzed. The lordotic cages used in all cases had 6-degree angle. Radiographic parameters including preoperative and postoperative segmental disc angle (SDA, preSDA and postSDA), SDA changes on flexion-extension views (ΔSDA-FE), CageLocation and CageInclination were measured by two observers. Interobserver reliability of measurements were ensured by analysis of interclass correlation coefficient (ICC > 0.75). Pearson correlation coefficient analysis and multivariate linear regression were employed to identify factors related to SDA changes and to build up predictive model for SDA changes.
RESULTS: The average change of segmental disc angle (ΔSDA, postSDA-preSDA) was 3.9° ± 4.8° (95% confidence interval [CI]: 3.1°-4.6°) with preSDA 5.3° ± 5.0°. ΔSDA was 10.8° ± 3.2° with negative preSDA (kyphotic), 5.0° ± 3.7° with preSDA ranging from 0° to 6°, and 1.0° ± 4.1° with preSDA> 6°. Correlation analysis revealed a significant negative correlation between ΔSDA and preSDA (r = - 0.713, P < 0.001), CageLocation (r = - 0.183, P = 0.016) and ΔSDA-FE (r = - 0.153, P = 0.044). In the multivariate linear regression, preSDA and CageLocation were included in the predictive model, resulting in minimal adjusted R2 change (0.017) by including CageLocation. Therefore, the recommended predictive model was ΔSDA = 7.9-0.8 × preSDA with acceptable fit. (adjusted R2 = 0.508, n = 174, P < 0.001).
CONCLUSIONS: The restoration of segmental lordosis through OLIF largely depends on the preoperative segmental lordosis. The predictive model, which utilized preoperative segmental lordosis, facilitates preoperative planning for corrective surgery using the OLIF procedure.
方法:这是一项前瞻性纳入患者的回顾性研究。共纳入并分析了119例接受OLIF手术的174段患者。在所有情况下使用的前凸笼具有6度角。影像学参数包括术前和术后节段椎间盘角度(SDA,前SDA和后SDA),屈伸视图上的SDA变化(ΔSDA-FE),由两名观察者测量CageLocation和CageExtination。通过类间相关系数分析(ICC>0.75)确保了观察者之间测量的可靠性。采用Pearson相关系数分析和多元线性回归来识别与SDA变化相关的因素,并建立SDA变化的预测模型。
结果:节段椎间盘角度的平均变化(ΔSDA,后SDA-preSDA)为3.9°±4.8°(95%置信区间[CI]:3.1°-4.6°),前SDA为5.3°±5.0°。ΔSDA为10.8°±3.2°,preSDA为负(后凸),5.0°±3.7°,PreSDA范围为0°至6°,和1.0°±4.1°,preSDA>6°。相关分析显示ΔSDA与preSDA呈显著负相关(r=-0.713,P<0.001),CageLocation(r=-0.183,P=0.016)和ΔSDA-FE(r=-0.153,P=0.044)。在多元线性回归中,预测模型中包含了PreSDA和CageLocation,通过包括CageLocation,导致最小的调整后R2变化(0.017)。因此,推荐的预测模型为ΔSDA=7.9-0.8×preSDA,拟合可接受。(调整后的R2=0.508,n=174,P<0.001)。
结论:通过OLIF恢复节段前凸很大程度上取决于术前节段前凸。预测模型,利用术前节段前凸,使用OLIF程序促进矫正手术的术前计划。