Influencing factors for difficult removal of locking head screws and locking compression plate

目的 分析锁定接骨板、锁定螺钉取出困难的相关因素,探讨相应的预防及应对措施.方法 回顾性分析2004年9月至2013年11月行锁定接骨板、锁定螺钉取出术的308例四肢骨折患者资料,男190例,女118例;平均年龄为36.8岁(12 ～ 82岁),骨折复位内固定术至内固定物取出术的时间间隔平均为16.3个月(2～56个月).骨折部位包括肱骨、尺桡骨、锁骨、股骨、胫骨及踝关节.观察是否出现内固定物取出困难,记录患者内固定物存留体内时间、锁定螺钉的直径、位置、置入方式、固定皮质数、锁定螺钉与接骨板是否垂直等.分别分析上肢和下肢骨折患者锁定接骨板、锁定螺钉取出困难的潜在影响因素,应用多因素logistic回归分析确定独立危险因素. 结果 37例患者出现锁定接骨板、锁定螺钉取出困难.肱骨远端、尺桡骨近端、股骨近端及股骨干内固定物取出困难发生率较高,分别为41.7％ (5/12)、33.3％ (1/3)、33.3％ (3/9)、33.3％ (1/3),踝关节内固定物取出困难发生率较低,为4.0％ (4/100).内固定物取出困难的独立危险因素:上肢骨折患者为内固定物存留体内时间长、年轻患者及双皮质固定(P＜0.05),下肢骨折患者为内固定物存留体内时间长、小直径螺钉及螺钉经皮置入(P＜0.05). 结论 为减少锁定接骨板固定术后内固定物取出困难的发生,建议在骨折愈合后尽早取出内固定物.不同部位内固定物取出困难的发生率及相关因素不同,术前决策及术中注意应各有侧重.Objective To analyze the factors that may lead to difficult removal of locking compression plate (LCP) and locking head screws (LHS).Methods We retrospectively reviewed medical records of the 308 patients with extremity fracture who underwent implant removal at our institution from September 2004 to November 2013.They were 190 males and 118 females,with an average age of 36.8 years (from 12 to 82 years).The mean interval from hardware implantation to removal was 16.3 months (from 2 to 56 months).Their fractures involved humerus,ulna,radius,clavicle,femur,tibia and ankle joint.We extracted the following data:difficulty in removal;duration of implant stay in the body;size,position,insertion technique and cortical purchase of LHS;positional relationship between LHS and LCP (orthogonal or non-orthogonal).After we identified potential factors that might have been associated with difficult removal of LHS and LCP in fractures of upper and lower limb respectively using Mann Whitney U test and Chi-square test,we used multiple logistic regression analysis to determine the independent influencing factors.Results Of the 308 patients we analyzed,difficult removal occurred in 37.Fractures at distal humerus had the highest incidence of difficult removal (41.7％),followed by fractures at proximal forearm (33.3％),proximal femur (33.3％) and femur shaft (33.3％).The incidence in malleolar fractures was low (4.0％).Logistic regression analysis suggested the following independent risk factors:long implant stay in the body,young age,and bicortical purchase of LHS for patients with upper extremity fracture (P ＜ 0.05);long implant stay in the body,LHS of a small diameter and percutaneous insertion of LHS for patients with lower extremity fracture (P ＜ 0.05).Conclusions If implant removal is indicated,surgery should be performed as soon as radiographs show fracture healing.To reduce the incidence of difficult removal of LHS and LCP,surgeons should in their preoperative plan and actual procedures take into account different fracture locations and different factors that may lead to difficulty in removal.中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)5405-4101