Chair of Medical Engineering, Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Aachen, Germany.
Niigata Hip Joint Center, Kameda Daiichi Hospital, Niigata City, Japan.
Sci Rep. 2020 Sep 29;10(1):15944. doi: 10.1038/s41598-020-72782-1.
The aims of this study were to investigate if the sagittal orientation of the pelvis (SOP) in the standing position changes after total hip arthroplasty (THA) and evaluate what preoperative factors may improve the prediction of the postoperative standing SOP in the context of a patient-specific functional cup orientation. 196 primary THA patients from Japan were retrospectively selected for this study. Computed tomography imaging of the pelvis, EOS imaging of the lower body and lateral radiographs of the lumbar spine in the standing position were taken preoperatively. Common biometrics and preoperative Harris Hip Score were recorded. The EOS imaging in the standing position was repeated three months following THA. A 3D/2.5D registration process was used to determine the standing SOP. Thirty-three preoperative biometric, morphological and functional parameters were measured. Important preoperative parameters were identified that significantly improve the prediction of the postoperative standing SOP by using multiple linear LASSO regression. On average, the SOP changed significantly (p < 0.001) between the preoperative and postoperative standing position three months after THA by 3° ± 4° in the posterior direction. The age, standing lumbar lordosis angle (LLA) and preoperative supine and standing SOP significantly (p < 0.001) improve the prediction of the postoperative standing SOP. The linear regression model for the prediction of the postoperative standing SOP is significantly (p < 0.001) improved by adding the parameters preoperative standing SOP and LLA, in addition to the preoperative supine SOP, reducing the root mean square error derived from a leave-one-out cross-validation by more than 1°. The mean standing SOP in Japanese patients changes already three months after THA in comparison to the preoperative value. The preoperative factors age, LLA, supine and standing SOP can significantly improve the prediction of the postoperative standing SOP and should be considered within the preoperative planning process of a patient-specific functional cup orientation.
本研究旨在探讨全髋关节置换术（THA）后骨盆矢状面位置（SOP）是否发生变化，并评估在特定于患者的功能性杯定向的术前因素中，哪些因素可以改善术后站立 SOP 的预测。从日本回顾性选择了 196 例初次 THA 患者。术前进行骨盆 CT 成像、下肢 EOS 成像和站立位腰椎侧位片。记录常见的生物测量和术前 Harris 髋关节评分。THA 后 3 个月重复进行 EOS 站立位成像。使用 3D/2.5D 配准过程确定站立 SOP。测量了 33 个术前生物测量、形态和功能参数。使用多元线性 LASSO 回归识别出重要的术前参数，这些参数可显著改善术后站立 SOP 的预测。THA 后 3 个月，与术前相比，SOP 在站立位时明显向后变化（p<0.001），平均为 3°±4°。年龄、站立腰椎前凸角（LLA）和术前仰卧位和站立位 SOP 显著（p<0.001）改善了术后站立 SOP 的预测。除了术前仰卧位 SOP 外，增加术前站立位 SOP 和 LLA 参数可显著（p<0.001）改善术后站立 SOP 的线性回归预测模型，通过留一交叉验证得出的均方根误差降低超过 1°。与术前值相比，日本患者的平均站立 SOP 在 THA 后 3 个月已经发生变化。术前因素年龄、LLA、仰卧位和站立位 SOP 可显著改善术后站立 SOP 的预测，应在患者特定的功能性杯定向术前规划过程中考虑这些因素。
