锁定钢板内置和外置治疗Sanders Ⅱ型跟骨骨折的疗效及其有限元分析

目的比较锁定钢板内置和外置治疗SandersⅡ型跟骨骨折的临床疗效和生物力学差异。方法将64例行锁定钢板治疗的SandersⅡ型跟骨骨折患者按照钢板内置和外置分为对照组(钢板内置,30例)和观察组(钢板外置,34例)。比较两组切口长度、手术时间、术中出血量、拆线时间、住院费用、B?hler角、Gissane角、AOFAS踝-后足功能评分以及并发症发生率。建立SandersⅡ型跟骨骨折有限元模型,分别予以锁定钢板内置和外置装配,在相同加载条件下比较两种模型稳定性。结果患者均获得随访,时间6~24个月。①手术时间、术中出血量、拆线时间观察组均明显优于对照组(P<0.05)。切口长度、住院费用两组比较差异无统计学意义(P>0.05)。末次随访B?hler角、Gissane角两组比较差异无统计学意义(P>0.05)。末次随访AOFAS评分观察组高于对照组(P<0.05)。并发症发生率两组比较差异无统计学意义(P>0.05)。②有限元模型:对两种方法的跟骨内固定模型进行载荷施加后,骨折线分离移位均<1 mm,跟骨最大应力位于跟骨结节周围,内固定最大应力位于载距突螺钉部位,应力强度均位于安全范围内。结论锁定钢板外置治疗SandersⅡ型跟骨骨折安全、有效、稳定性可靠,为临床决策提供了新思路。

Preparation and Properties of Plywood Adhesives with Soy Protein Isolate Modified by SDS

The effects of mass concentration,the reaction temperature and the reaction time of soy protein isolate(SPI) and sodium dodecyl sulfate (SDS) on the adhesive strength of the modified SPI adhesives has been studied through orthogonal experiments.And the adhesive mechanism of the modified SPI adhesives was discussed.The results show that the optimum formula conditions are as follows:mass concentration of SPI was 14%,that of SDS 1%,reaction temperature 35℃and the reaction time 3 h.Under the optimum conditions, the dry adhesive strength of the modified SPI adhesives was 1.82 MPa,the wet adhesive strength was 0.82 MPa,the viscosity was 5.8 Pa·s,the solid content was 12.96%.After SDS was added into SPI, the composites of SDS-SPI were formed,the internal hydrophobic groups among the SPI molecule structure were turned out and the water resistance of the modified SPI adhesives was enhanced with an increase of the modification time.When the concentration of SDS was over a defined value,the disulfide bond was broken and the modification effect of SDS went bad.