Boudali A Mounir, Chai Yuan, Farey John E, Vigdorchik Jonathan, Walter William L
Sydney Musculoskeletal Health and The Kolling Institute, Northern Clinical School, Faculty of Medicine and Health and the Northern Sydney Local Health District, Sydney, NSW, Australia.
Institute of Future Health, South China University of Technology, Guangzhou, China.
Hip Int. 2025 Jan;35(1):41-46. doi: 10.1177/11207000241282984. Epub 2024 Sep 23.
Pelvic incidence - lumbar lordosis (PI-LL) mismatch is often considered when assessing spinopelvic alignment in the sagittal plane. The mismatch is conventionally obtained by measuring 2 separate angles on lateral spinopelvic radiographs. This study describes a simplified approach for assessing spinopelvic mobility and measuring the PI-LL mismatch through the evaluation of the L1-spinopelvis angle (L1SP).
96 standing lateral radiographs were obtained from consecutive patients presenting for total hip arthroplasty between November 2020 and July 2021. 3 operators were recruited to annotate landmarks on digital radiographs. Correlation analysis and error analysis were applied. Measurement reproducibility was assessed using intraclass correlation coefficient (ICC).
The correlation coefficients of the 3 variables were respectively 0.87 for PI, 0.94 for LL, and 0.96 for L1SP. The normalised root mean square error between the 2 measurement sets was 9.96% for PI, 5.97% for LL, and 4.41% for L1SP. The absolute error was 3.49° ± 4.63° for PI, 3.23° ± 3.78° for LL, 2.68° ± 3.19° for PI-LL conventional, and 2.35° ± 2.88° for PI-LL via L1SP, respectively. In terms of reproducibility, measurement of L1SP outperformed that of PI and LL (ICC = 0.97 versus 0.83 and 0.93, respectively).
The simplified L1SP method, through the measurement of a single angle, produced similar measurements to the conventional PI-LL method. The measurement repeatability between operators was improved using the L1SP method. From a clinical practice perspective, both methods are equivalent. The new method is readily reproducible using commercially available PACS software during preoperative templating.
在评估矢状面脊柱骨盆对线时，通常会考虑骨盆入射角-腰椎前凸角（PI-LL）不匹配。传统上，这种不匹配是通过在脊柱骨盆侧位X线片上测量两个独立的角度来获得的。本研究描述了一种通过评估L1-脊柱骨盆角（L1SP）来评估脊柱骨盆活动度和测量PI-LL不匹配的简化方法。
收集了2020年11月至2021年7月期间连续接受全髋关节置换术患者的96张站立位侧位X线片。招募了3名操作人员在数字X线片上标注标志点。应用相关性分析和误差分析。使用组内相关系数（ICC）评估测量的可重复性。
三个变量的相关系数分别为：PI为0.87，LL为0.94，L1SP为0.96。两组测量值之间的标准化均方根误差分别为：PI为9.96%，LL为5.97%，L1SP为4.41%。绝对误差分别为：PI为3.49°±4.63°，LL为3.23°±3.78°，传统PI-LL为2.68°±3.19°，通过L1SP测量的PI-LL为2.35°±2.88°。在可重复性方面，L1SP的测量优于PI和LL（ICC分别为0.97、0.83和0.93）。
简化的L1SP方法通过测量单个角度，得到的测量结果与传统的PI-LL方法相似。使用L1SP方法提高了操作人员之间测量的可重复性。从临床实践角度来看，两种方法等效。在术前模板制作过程中，使用商用PACS软件，新方法易于重复操作。
