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

Efficacy and finite element analysis of locking plate with internal and external fixation for Sanders type Ⅱ calcaneal fracture

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。

Objective To compare the differences of clinical efficacy and biomechanical between locking plate internal fixation and external fixation in the treatment of Sanders typeⅡcalcaneal fractures.Methods The 64 cases treated with locking plate of internal and external plates were divided into control group(30 cases were used of internal plate)and observation group(34 cases were fixed with external plate).The following data were compared,including the length incision,operation time,blood loss,suture removal time,hospital costs,B?hler angle and Gissane angle,AOFAS ankle-hindfoot function score and complication incidence rate.The finite element model of SandersⅡfracture of calcaneus was made,which was fixed by the locking plate with internal and external fixation,respectively,the stability of the two models under the same loading condition was compared.Results All patients were followed up for 6~24 months.①The operative time,intraoperative blood loss,suture removal time of the observation group were all better than those of the control group(P<0.05).At the last follow-up,there were no statistically significant differences for B?hler angle and Gissane angle between two groups(P>0.05).AOFAS score:the observation group was higher than the control group(P<0.05).Complication incidence rate:there was no statistically significant difference between the two groups(P>0.05).②Fixed model finite element model:after applying a load to the two methods of calcaneal internal fixation model,fracture line shifted of model were all less than 1 mm,the maximum stress loading of calcaneus was located around the calcaneal tuberosity,the maximum stress of internal fixaiton was located in the middle of the plate,the stress intensity were all in the safe range.Conclusions Locking plate external fixation is safer,more effective and more reliable for Sanders typeⅡcalcaneal fracture,and which provides a new idea for clinical decision making.