Service de chirurgie orthopédique et réparatrice de l'enfant, hôpital Armand-Trousseau, 26, avenue du Dr-Netter, 75012 Paris, France; Arts et metiers ParisTech, LBM/Institut de biomécanique humaine Georges-Charpak, 151, boulevard de l'Hôpital, 75013 Paris, France.
Arts et metiers ParisTech, LBM/Institut de biomécanique humaine Georges-Charpak, 151, boulevard de l'Hôpital, 75013 Paris, France.
Orthop Traumatol Surg Res. 2018 Sep;104(5):617-622. doi: 10.1016/j.otsr.2018.04.018. Epub 2018 Jun 13.
Adolescent idiopathic scoliosis (AIS) can require surgical procedures that have major consequences. Coronal imbalance as assessed clinically using a plumb line is a key criterion for selecting patients to surgery. Nevertheless, the reference standard for assessing postural balance of the trunk is gravity line localisation within a validated frame of reference. Recent studies have established that the gravity line can be localised after body contour reconstruction from biplanar radiographs. The objective of this study was to validate a gravity line localisation method based on biplanar radiographs in a population with AIS then to validate gravity line position versus plumb line position.
Plumb line and gravity line assessments of coronal balance correlate with each other.
A gravity line localisation method based on biplanar radiography was validated in 14 patients with AIS versus force platform as the method of reference. Normal plumb line and gravity line positions were determined in 27 asymptomatic adolescents using biplanar radiography. The results of the two methods were then compared in 53 patients with AIS.
The reliability of gravity line localisation in the coronal plane based on biplanar radiography was 2.4mm (95% confidence interval). The distance between the gravity line and the middle of the line connecting the centres of the two femoral heads (HA) showed a strongly significant association with plumb line position computed as the distance from the vertical line through the middle of T1 and the centre of the S1 endplate (T1V/S): r=0.71, p<0.0001. Of the 20 patients with plumb line results indicating coronal imbalance, 11 (55%) had a normal gravity line-to-HA distance. Of the 33 patients with normal plumb line results, 7 (21%) had an abnormal gravity line-to-HA distance.
The results of this study validate gravity line determination from biplanar radiographs in a population with AIS. Plumb line position correlated significantly with gravity line position but was less accurate for guiding surgical decisions.
IV, retrospective study.
青少年特发性脊柱侧凸（AIS）可能需要手术治疗，这些手术会产生重大影响。临床使用铅垂线评估的冠状面失衡是选择手术患者的关键标准。然而，评估躯干姿势平衡的参考标准是在经过验证的参考框架内定位重力线。最近的研究已经证实，在双平面 X 射线重建身体轮廓后，可以定位重力线。本研究的目的是验证 AIS 患者双平面 X 射线的重力线定位方法，然后验证重力线位置与铅垂线位置的关系。
铅垂线和重力线评估的冠状面平衡相互关联。
基于双平面 X 射线的重力线定位方法在 14 例 AIS 患者中进行了验证，以力平台作为参考方法。使用双平面 X 射线确定了 27 名无症状青少年的正常铅垂线和重力线位置。然后，将这两种方法在 53 例 AIS 患者中进行了比较。
基于双平面 X 射线的冠状面重力线定位的可靠性为 2.4mm（95%置信区间）。重力线与连接两个股骨头（HA）中心的线的中点之间的距离与铅垂线位置（通过 T1 中点和 S1 终板中心的垂线与 T1V/S 之间的距离来计算）呈强显著相关性：r=0.71，p<0.0001。在铅垂线结果显示冠状面失衡的 20 例患者中，有 11 例（55%）的重力线到 HA 的距离正常。在铅垂线结果正常的 33 例患者中，有 7 例（21%）的重力线到 HA 的距离异常。
本研究结果验证了 AIS 患者双平面 X 射线的重力线确定方法。铅垂线位置与重力线位置显著相关，但在指导手术决策方面准确性较低。
IV，回顾性研究。
