Acar Baver, Köse Özkan, Turan Adil, Katı Yusuf Alper, Güler Ferhat
Department of Orthopedics and Traumatology, University of Health Sciences, Antalya Training and Research Hospital, Antalya, Turkey.
Jt Dis Relat Surg. 2020;31(1):73-80. doi: 10.5606/ehc.2020.71521.
This study aims to compare the single versus double screw fixation of scaphoid waist fractures using finite element analysis, and to present the preliminary clinical results of double screw fixation in a consecutive series of patients with scaphoid nonunion.
A transverse scaphoid waist fracture (Herbert type B2) model was fixed with either single or double cannulated compression screws. Displacement and rotation of the fragments were performed using three-dimensional finite element analysis in three different wrist positions. A retrospective review was performed on 13 male patients (mean age 31.6±12.8 years; range, 17 to 64 years) who underwent double screw fixation for an established scaphoid nonunion in our clinic between January 2015 and December 2017. Assessment of union was established with serial plain radiographs in eight patients and with wrist computed tomography in five patients. Clinical evaluation was performed using the Mayo wrist score and visual analog scale (VAS).
In all wrist positions, the displacement of the fracture gap in double screw fixation in all planes (x, y, and z) was less than in single screw fixation. Similarly, rotation of the fracture fragments around the longitudinal axis of the scaphoid was lower in double screw fixation. Complete union was obtained in all patients. The mean time to union was 5±0.75 months (range, 4 to 6 months). The mean VAS was 0.8±0.9 (range, 0 to 3). Mayo wrist score was 91±6.9 (range, 80 to 100) at the final follow-up.
Double-screw fixation technique may be a solution to reduce the rate of scaphoid nonunion in unstable type B2 scaphoid fractures or nonunion.
本研究旨在通过有限元分析比较舟状骨腰部骨折的单枚与双枚螺钉固定，并展示双枚螺钉固定在一系列舟状骨不愈合患者中的初步临床结果。
采用单枚或双枚空心加压螺钉固定横向舟状骨腰部骨折（Herbert B2型）模型。在三种不同的腕部位置使用三维有限元分析来观察骨折块的位移和旋转情况。对2015年1月至2017年12月期间在我院接受双枚螺钉固定治疗陈旧性舟状骨不愈合的13例男性患者（平均年龄31.6±12.8岁；范围17至64岁）进行回顾性研究。8例患者通过系列X线平片评估愈合情况，5例患者通过腕部计算机断层扫描评估愈合情况。使用Mayo腕关节评分和视觉模拟量表（VAS）进行临床评估。
在所有腕部位置，双枚螺钉固定时骨折间隙在所有平面（x、y和z）的位移均小于单枚螺钉固定。同样，双枚螺钉固定时骨折块围绕舟状骨纵轴的旋转也较小。所有患者均实现完全愈合。平均愈合时间为5±0.75个月（范围4至6个月）。平均VAS为0.8±0.9（范围0至3）。末次随访时Mayo腕关节评分为91±6.9（范围80至100）。
双枚螺钉固定技术可能是降低不稳定型B2舟状骨骨折或不愈合时舟状骨不愈合率的一种解决方法。
