全膝关节置换后双下肢长度及相关功能变化

文题释义：膝关节置换：一种治疗膝关节终末期病变的手术方式,可明显减轻患者膝关节疼痛,改善膝关节功能,但尚有约20%患者存在术后不满意情况,需进一步研究加以改善。下肢全长片：完整呈现全部下肢解剖结构的影像记录方法,可用于评估下肢总体力线(髋膝踝角)及下肢功能长度,为膝关节置换提供术前参考及术后功能评价。背景：膝关节置换后功能不佳的原因有许多,下肢不等长作为其中的一种,对膝关节置换后功能的影响程度尚未被充分研究。目的：分析全膝关节置换后患者下肢不等长的变化程度、可能影响因素及功能变化。方法：收集徐州医科大学附属医院骨科自2016年10月至2018年9月行全膝关节置换患者107例(124膝),男23例,女84例。单侧全膝关节置换90例(90膝),双侧全膝关节置换17例(34膝),其中分次双侧全膝关节置换且间隔时间超过6个月的3例(6膝)并入单膝组;因此单膝组共93例(96膝),双膝组14例(28膝)。患者对治疗及试验方案知情同意,且得到医院伦理委员会批准。分别于术前、术后10 d及术后6个月拍摄患者站立位下肢全长正位片并测量记录下肢长度及髋膝踝角,大体测量膝关节屈曲挛缩角并记录美国特种外科医院膝关节评分。结果与结论：①全膝关节置换后患者下肢长度随着畸形矫正而增长,术后6个月下肢长度长于术后10 d,术后10 d 时70.2%的患者下肢增长,术后6个月79.0%的患者肢体增长;②术后10 d及术后6个月时,术后屈曲挛缩角矫正量与术后下肢长度变化量呈正相关;③术侧肢体延长程度与术后美国特种外科医院膝关节评分增量呈正相关;④术前与术后下肢不等长发生率接近,术前为45.1%,术后10 d为 55.3%,术后6个月为46.0%;⑤术前及术后6个月下肢不等长受双下肢畸形差值影响,术前的影响因素为双下肢髋膝踝角差值及双下肢屈曲挛缩角差值;术后6个月时影响下肢不等长的因素是双下肢屈曲挛缩角差值;术前及术后6个月时下肢不等长影响双下肢美国特种外科医院膝关节评分差值。ORCID: 0000-0002-9642-4136(唐金龙)中国组织工程研究杂志出版内容重点：人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程

Change of related functions and double lower limb length after total knee arthroplasty

BACKGROUND:There are many reasons for poor function after knee arthroplasty.Leg length discrepancy is one of them.The extent of influence on the function of knee joint after arthroplasty has not been fully studied.OBJECTIVE:To analyze the change degree,possible influencing factors and functional changes of leg length discrepancy in patients after total knee arthroplasty.METHODS:Totally 107 patients(124 knees),including 23 males and 84 females,were included from October 2016 to September 2018,who entered the Department of Orthopedics of Affiliated Hospital of Xuzhou Medical University for total knee arthroplasty.There were 90 cases of unilateral total knee arthroplasty(90 knees)and 17 cases of bilateral total knee arthroplasty(34 knees).Three cases(6 knees)of bilateral total knee arthroplasty received separate treatment with an interval of more than 6 months,and entered the unilateral knee group.Therefore,there were 93 cases(96 knees)in the unilateral knee group,and 14 cases(28 knees)in the bilateral knee group.Patients signed the informed consent.This study was approved by the Hospital Ethics Committee.At preoperative and postoperative 10 days and 6 months,full length anteroposterior radiographs were taken,and the length of the lower limb and hip-knee-ankle angle were measured and recorded.Angle of knee flexion contracture was measured and the hospital for special surgery knee score was recorded.RESULTS AND CONCLUSION:(1)The length of patients’lower limbs was increased by the correction of deformities after total knee arthroplasty.The length of lower limbs 10 days after surgery was longer than that at 6 months after surgery.The lower limbs of 70.2%of the patients were increased 10 days after total knee arthroplasty,and 79.0%of the patients were increased 6 months after total knee arthroplasty.(2)At 10 days and 6 months postoperatively,the postoperative corrected flexion contracture angles were positively correlated with the change of postoperative lower limb length.(3)Limb lengthening on the operative side was positively correlated with increased hospital for special surgery knee score after surgery.(4)The incidence of leg length discrepancy before and after surgery was almost equal:45.1%preoperatively,55.3%10 days postoperatively,and 46.0%6 months postoperatively.(5)The leg length discrepancy preoperatively and 6 months postoperatively was influenced by the difference of deformities between the pair of limbs.Preoperative influencing factors were the difference of hip-knee-ankle angle and flexion contracture of both lower limbs.The difference value of flexion contracture of both lower limbs was the factor affecting the leg length discrepancy 6 months after surgery.Leg length discrepancy before surgery and 6 months after surgery was affecting the difference of hospital for special surgery knee score between lower limbs.