Department of Mechanical Engineering, Polytechnique Montreal, Montreal (Quebec), Canada.
Sainte-Justine University Hospital Center, Montreal (Quebec), Canada.
Stud Health Technol Inform. 2021 Jun 28;280:150-152. doi: 10.3233/SHTI210455.
The objective was to assess deformity correction and bone-screw force associated respectively with concave manipulation first, convex manipulation first, and different differential rod contouring configurations. Instrumentation scenarios were computationally simulated for 10 AIS cases with mean thoracic Cobb angle (MT) of 54±8°, apical vertebral rotation (AVR) of 19±2° and thoracic kyphosis of 21±9°. Instrumentations with major correction maneuvers using the concave side rod were first simulated; instrumentations with major correction maneuvers using the convex side rod were then simulated. Simulated correction maneuvers were concave/convex rod translation followed by apical vertebral derotation and then convex/concave rod translation. There were no significant differences in deformity corrections and bone-screw forces between concave rod translation first and convex rod translation first with differential rod contouring. Increasing differential rod contouring angle and concave rod diameter improved AVR correction and increased the TK and bone-screw forces; the effect on the MT Cobb angle was not clinically significant.
目的在于评估分别采用凹侧手法、凸侧手法以及不同的差动杆轮廓构型首先进行凹侧手法操作时的畸形矫正和骨螺钉力。针对平均胸弯 Cobb 角（MT）为 54±8°、顶椎旋转（AVR）为 19±2°和胸曲 21±9°的 10 例 AIS 患者进行了器械模拟。首先模拟使用凹侧杆进行主要矫正操作的器械；然后模拟使用凸侧杆进行主要矫正操作的器械。模拟的矫正操作步骤为凹侧/凸侧杆平移，随后进行顶椎椎体旋转，然后再进行凸侧/凹侧杆平移。在差动杆轮廓的情况下，凹侧杆平移和凸侧杆平移在畸形矫正和骨螺钉力方面没有显著差异。增加差动杆轮廓角度和凹侧杆直径可以改善 AVR 矫正，并增加胸曲和骨螺钉力；但对 MT Cobb 角的影响无临床意义。
