Aims The objective of this study was to compare simulated range of motion (ROM) for reverse total shoulder arthroplasty (rTSA) with and without adjustment for scapulothoracic orientation in a global reference system. We hypothesized that values for simulated ROM in preoperative planning software with and without adjustment for scapulothoracic orientation would be significantly different. Methods A statistical shape model of the entire humerus and scapula was fitted into ten shoulder CT scans randomly selected from 162 patients who underwent rTSA. Six shoulder surgeons independently planned a rTSA in each model using prototype development software with the ability to adjust for scapulothoracic orientation, the starting position of the humerus, as well as kinematic planes in a global reference system simulating previously described posture types A, B, and C. ROM with and without posture adjustment was calculated and compared in all movement planes. Results All movement planes showed significant differences when comparing protocols with and without adjustment for posture. The largest mean difference was seen in external rotation, being 62° (SD 16°) without adjustment compared to 25° (SD 9°) with posture adjustment (p < 0.001), with the highest mean difference being 49° (SD 15°) in type C. Mean extension was 57° (SD 18°) without adjustment versus 24° (SD 11°) with adjustment (p < 0.001) and the highest mean difference of 47° (SD 18°) in type C. Mean abducted internal rotation was 69° (SD 11°) without adjustment versus 31° (SD 6°) with posture adjustment (p < 0.001), showing the highest mean difference of 51° (SD 11°) in type C. Conclusion The present study demonstrates that accounting for scapulothoracic orientation has a significant impact on simulated ROM for rTSA in all motion planes, specifically rendering vastly lower values for external rotation, extension, and high internal rotation. The substantial differences observed in this study warrant a critical re-evaluation of all previously published studies that examined component choice and placement for optimized ROM in rTSA using conventional preoperative planning software.

中文翻译：

---

2024 年 SECEC Grammont 奖：姿势调整在反向全肩关节置换术术前计划中对运动范围模拟的关键作用。


目的 本研究的目的是在整体参考系统中比较反向全肩关节置换术 （rTSA） 的模拟运动范围 （ROM），有和没有肩胛胸方向调整。我们假设术前计划软件中模拟 ROM 的值在调整和不调整肩胛胸方向的情况下会显着不同。方法 将整个肱骨和肩胛骨的统计形状模型拟合到 10 例接受 rTSA 的患者随机选择的 10 例肩部 CT 扫描中。六名肩部外科医生使用原型开发软件在每个模型中独立规划了一个 rTSA，该软件能够调整肩胛胸方向、肱骨的起始位置以及全球参考系统中的运动平面，模拟先前描述的姿势类型 A、B 和 C. ROM有和没有姿势调整在所有运动平面上被计算和比较。结果 在比较调整姿势和不调整姿势的方案时，所有运动平面均显示出显着差异。最大的平均差异见于外旋，无调整为 62° （SD 16°） 与有姿势调整的 25° （SD 9°） 相比 （p < 0.001），最高平均差为 49° （SD 15°） C 型。平均伸展为 57° （SD 18°） 无调整，与 24° （SD 11°） 有调整 （p < 0.001） 和 C 型最高平均差为 47° （SD 18°） 。平均外展内旋为 69° （SD 11°）无调整与有姿势调整的 31° （SD 6°） （p < 0.001） 相比，C 型的平均差异最高，为 51° （SD 11°）。 结论 本研究表明，考虑肩胛胸方向对所有运动平面中 rTSA 的模拟 ROM 有显着影响，特别是外旋、伸展和高内旋的值大大降低。本研究中观察到的实质性差异值得对所有先前发表的研究进行批判性的重新评估，这些研究使用传统的术前计划软件检查了 rTSA 中优化 ROM 的组件选择和放置。