PFNA治疗股骨转子间骨折刀片过度侧方滑移的危险因素分析

The risk factors of excessive lateral migration of blade among femoral intertrochanteric fracture patients treated with PFNA

目的:探讨防旋股骨近端髓内钉(proximal femoral nail antirotation,PFNA)治疗股骨转子间骨折术后螺旋刀片发生过度侧方滑移的危险因素。方法:回顾性分析2011年4月—2016年3月在江苏大学附属医院行PFNA内固定治疗且有完整随访资料的163例股骨转子间骨折患者的临床资料,其中男84例,女79例,年龄50~99岁(平均69.9岁)。测量并收集其影像学指标,包括:股骨近端外侧壁是否破损、小转子是否移位、术后尖顶距(tip-apex distance,TAD)、术后股骨距尖顶距(calcar referenced tip-apex distance,Cal-TAD)、术后即时以及末次随访螺旋刀片相对于主钉中心外露部分长度、断端支撑模式。同时记录患者的Singh指数、AO/OTA分型。建立Logistic回归模型,分析螺旋刀片过度滑移的危险因素。结果:163例患者中18例出现螺旋刀片过度滑移。单因素分析显示:AO/OTA分型、小转子是否移位和断端支撑情况与螺旋刀片过度滑移有关(P<0.05),而Singh指数、复位等级、外侧壁是否破损、TAD、Cal-TAD、性别、年龄与过度滑移无关(P>0.05)。Logistic回归分析提示:骨折稳定性和断端支撑情况是刀片过度滑移的危险因素(P<0.05)。结论:不稳定性骨折和阴性支撑是PFNA治疗股骨转子间骨折术后螺旋刀片过度侧方滑移的危险因素,使用时需注意延迟下地负重时间。

Objective：To explore the risk factors of blade excessive lateral migration among femoral intertrochanteric fracture fixed with proximal femoral nail anti-rotation（PFNA）. Methods：A total of 163 intertrochanteric fracture patients（mean 69.9 years old）who received PFNA fixation from April 2011 to March 2016 in the Affiliated Hospital of Jiangsu University were retrospectively evaluated.There were 84 male patients and 79 female patients aged from 50 to 99 years（mean age of 69.6 years）. The radiological parameters were measured,including the condition of proximal lateral wall（broken or not）,the position of lesser trochanter（displaced or not）,tipapex distance（TAD）,calcar referenced tip-apex distance（Cal-TAD）,the amount of lateral migration of the blade and medial cortex support mode. Singh index and AO/OTA type were also recorded. Logistic regression model was established to analyze the key factors causing excessive lateral sliding of blade. Results：We found that 18 cases showed radiographic over lateral migration. The univariate analysis illustrated that the excessive lateral migration of blade directly related to unstable fracture type,displaced lesser trochanter,and negative medial cortex support（P〈0.05）,but not Singh index,calcar reduction,lateral wall injury,TAD,Cal TAD,age and gender（P〈0.05）. Multiple logistic regression suggested that unstable fracture pattern and negative medial cortex support were independent risk factors of blade excessive lateral migration（P〈0.05）. Conclusion：For femoral intertrochanteric fracture patients treated with PFNA,over lateral sliding of blade may occur. The risk factors include unstable fracture pattern and negative medial cortex support.PFNA should be used cautiously in those with the hazard factors,and weightbearing ambulation must be delayed.