不同类型假体全膝关节置换术后的运动学分析

目的观察以后稳定型、固定平台保留后十字韧带型和移动平台保留后十字韧带型假体行全膝关节置换术(TKA)后膝关节最大屈曲度,及膝关节屈曲过程中股骨假体相对胫骨假体的前后移动距离,探讨屈膝时股骨的前后移动对膝关节最大屈曲度的影响。方法选取以三种类型假体行TKA术的病例各25例,均为膝骨性关节炎;TKA术后效果优良,膝关节屈曲≥90°,术后1年以上。患者年龄63～77岁,平均68岁;男32膝,女43膝。后稳定型组、固定平台组及移动平台组术前膝关节最大屈曲度分别为77.8°±15.1°、80.1°±12.9°和76.4°±12.7°。术后拍摄膝伸直位和最大被动屈曲位侧位X线片,测量膝关节从伸直位至最大屈曲位时股骨假体相对胫骨假体的前后移动距离及膝最大屈曲度。结果三组术前屈膝度差异无显著性。后稳定型组、固定平台组和移动平台组术后最大屈曲度分别为118.0°±7.1°、108.7°±7.9°和100.2°±8.3°,三组差异有非常显著性(F=32.86,P=0.0001)。三组术后股骨假体相对胫骨假体前后移动距离分别为(6.3±2.5)mm、(?1.2±4.6)mm和(?4.7±3.7)mm(向后移为正值,向前移为负值),三组差异有非常显著性(F=57.71,P=0.0001)。股骨假体相对胫骨假体前后移动距离与膝最大屈曲度间存在相关性,股骨假体前移会使膝最大屈曲度减小。结论三     

CT扫描确定全膝关节置换股骨假体旋转力线的研究

目的探讨术前CT扫描对全膝关节置换(TKA)中股骨假体旋转力线精确确定的作用。方法将200例(252膝)TKA患者随机分为两组:①经验组(64例):TKA术中根据术者触摸外科股骨上髁轴线联合Whi-teside线联合确定股骨假体外旋角度;②CT扫描组(136例):术前CT扫描确定股骨后髁角,术中采用可调外旋定位器复制CT确定的外旋角度,其余TKA手术操作相同。两组术后均行CT扫描确定股骨假体旋转不良角度并对其绝对值进行比较。结果经验组TKA术后股骨假体旋转不良角度为2.8°±0.14°,CT扫描组为1.2°±0.04°,两组比较差异有统计学意义(t=4.18,P<0.01)。经验组股骨假体旋转不良率为32.1%,CT扫描组为18.5%,两组比较差异有统计学意义(χ2=17.47,P<0.01)。结论术前CT扫描确定股骨远端后髁角可以有效提高TKA手术股骨假体旋转力线,方法简单、有效、重复性良好。     

CT扫描在全膝关节置换术中髌股关节轨迹不良股骨旋转力线的研究

[目的]探讨CT扫描技术检测全膝关节置换术(TKA)中对髌股关节轨迹不良股骨旋转截骨角度确定的作用。[方法]将72例(74膝)TKA中髌股关节轨迹不良患者随机分为两组:(1)CT扫描组35例(36膝):术前CT扫描确定股骨后髁角,术中采用CT确定的股骨后髁角进行股骨外旋截骨,其余TKA手术操作相同;(2)对照组37例(38膝):术中采用与后髁轴线呈固定外旋3°进行股骨外旋截骨,两组术后均行CT扫描分析股骨假体旋转不良角度并对其绝对值进行比较。[结果]术后随访时间24¹20个月,平均53.6个月。CT扫描组KSS功能评分从术前的平均35分提高到术后平均81分;对照组KSS功能评分从术前的平均34分提高到术后平均83分,两组比较均无显著性差异(P>0.05)。CT扫描组:TKA术后股骨假体旋转不良角度为1.4°±0.06°,对照组为2.5°±0.14°,两组比较差异有统计学意义(t=4.18,P<0.01)。CT扫描组股骨假体旋转不良率为12.5%,经验组为24.6%,两组比较差异有统计学意义(x2=16.58,P<0.01)。[结论]术前CT扫描确定股骨假体旋转参考轴,可用于指导全膝关节置换术中股骨旋转截骨角度,有效提高TKA手术股骨假体旋转力线的准确性。     

个体化股骨远端外翻角度截骨技术在初次人工全膝关节置换术中的应用

目的探讨初次人工全膝关节置换术(total knee arthroplasty,TKA)中,应用个体化股骨远端外翻角度截骨技术对改善术后下肢冠状面力线的可行性以及疗效。方法回顾分析2013年1月-2月接受单膝TKA并符合选择标准的50例退行性骨关节炎患者临床资料。其中25例TKA中采用个体化股骨远端外翻角度截骨技术(试验组),25例采用传统股骨远端外翻5°截骨技术(对照组)。两组患者性别构成、年龄、身体质量指数、病程、患膝侧别、骨关节炎分级以及术前股骨解剖轴夹角(femoral mechanical anatomical angle,FMA)、机械胫股角(mechanical femorotibial angle,MFT)、膝关节学会评分系统(KSS)比较,差异均无统计学意义(P0.05)。术后3 d摄下肢全长X线片,测量并比较两组MFT;术后6、15个月采用KSS评分评价膝关节功能。结果术后3d X线片示试验组MFT为(—0.20±1.87)°,对照组为(1.71±3.67)°,比较差异有统计学意义(t=2.32,P=0.02);其中试验组22例(88%)MFT达理想角度(0±3)°,显著高于对照组的16例(64%)(χ2=2.32,P=0.02)。两组切口均Ⅰ期愈合,无下肢深静脉血栓形成等并发症发生。两组患者术后均获随访15个月,试验组术后6、15个月膝关节KSS评分分别为(88.23±2.57)、(90.76±2.77)分,显著高于对照组的(82.92±2.59)、(88.65±1.77)分,比较差异均有统计学意义(t=7.26,P=0.00;t=3.20,P=0.02)。末次随访X线片示假体均无松动征象。结论与传统股骨远端外翻5°截骨技术相比,初次TKA中采用个体化股骨远端外翻角度截骨技术可更好改善MFT角,有利于膝关节功能的早期恢复。     

五合一股骨截骨技术在全膝关节置换术中的应用

目的 探讨应用五合一股骨截骨技术和Deluxe-ps型假体行人工膝关节置换术的近期疗效.方法 2008年10月至2009年12月,应用股骨五合一截骨法采用Deluxe-ps型膝关节假体行TKA手术20例,25膝.对照组为同期应用传统股骨四合一截骨技术,采用Depuy P.F.C.Sigma型膝关节假体行TKA手术17例,22膝.术中测量五合一截骨后各平面夹角和股骨远端前后径距离,计算各角度、距离与对应假体设计参数的差值.术后X线片测量两组外翻角、股骨假体屈曲角以评估股骨侧假体位置.采用KSS评分和功能评分、膝关节ROM评估两组手术前、后膝关节功能.结果 两组所有患者均获得随访6～20个月,平均12个月.本组五合一截骨后各平面夹角、股骨远端前后径距离与对应假体设计参数的差值,差异无统计学意义,两组术前、术后随访KSS评分和功能评分、膝关节ROM差异有统计学意义,两组术后随访KSS评分和功能评分、膝关节ROM差异无统计学意义.两组术后X线片评定假体位置、力线、固定性能等均显示良好,其中外翻角、股骨假体屈曲角与对照组比较差异无统计学意义.结论 初次TKA手术采用五合一股骨截骨技术和Deluxe-ps型假体术后近期疗效满意.     

股骨后髁偏心距在全膝关节置换术中的意义

股骨后髁偏心距(PCO)这一概念由Bellmans于2002年率先提出,最早被认为与全膝关节置换术(TKA)后膝关节屈曲度相关。目前,PCO的测量方法主要包括4种：X线测量法简便易行,但因其忽略了股骨内外侧髁的不对称性,在原理上存在一定缺陷;CT、MRI法不受投照角度限制,但假体金属伪影的干扰不可忽略;影像学结合术中软骨厚度测量最为精确,但操作复杂并且主观性较强。PCO在TKA术中有着重要的临床意义：对于后交叉韧带保留型TKA,PCO通过影响股骨与胫骨撞击的旋转半径,使得膝关节最大屈曲度与之正相关。而在后交叉韧带替代型TKA中却没有这种关系,这可能与膝关节后方软组织的阻挡作用以及膝关节前方伸膝装置的限制作用有关。此外,PCO的改变会影响屈曲间隙,从而影响膝关节稳定性特别是屈曲位和半屈位的稳定性。这种改变同样会影响膝关节的解剖学结构及生物力学结构,进而有可能导致骨溶解及假体松动。过大的PCO会增加后方关节囊的紧张程度,造成伸直间隙的减小,带来膝关节屈曲挛缩的风险。因此在TKA术中,临床工作者有必要尽可能将PCO恢复到术前状态,以最大限度避免相应不良后果的发生。本文就PCO在TKA术中的临床意义作以综述。     

Gemini MK-Ⅱ活动垫片膝关节假体置换术中胫骨结节内1/3解剖定位法对胫骨假体旋转力线的影响

目的探讨采用Gemini MK-Ⅱ活动垫片膝关节假体行人工全膝关节置换术(total knee arthroplasty,TKA)中,采用胫骨结节内1/3解剖定位法对胫骨假体旋转力线的影响。方法回顾分析2011年3月-2012年12月采用Gemini MK-Ⅱ活动垫片膝关节假体行TKA治疗的61例(67膝)内翻型膝关节骨关节炎患者临床资料。男12例,女49例;年龄50~82岁,平均67.6岁。体质量指数20.9~33.7 kg/m2,平均28.2 kg/m2。单膝55例,双膝6例。病程2~30年,平均12.1年。骨关节炎Kellgren-Lawrence分级:Ⅲ级56膝,Ⅳ级11膝。术中采用后交叉韧带中点至胫骨结节内1/3连线确定胫骨假体旋转轴。对手术前后膝关节正侧位X线片及CT进行测量,分析术后胫骨假体旋转情况。结果患者均获随访,随访时间18~41个月,平均20.5个月。术前及末次随访时膝关节活动度分别为(98.806±16.969)、(116.806±11.458)°,KSS评分分别为(111.239±20.344)、(160.522±17.872)分,末次随访时均明显优于术前(t=—11.760,P=0.000;t=—27.271,P=0.000)。影像学检查示,末次随访时胫股解剖角(anatomic tibiofemoral angle,ATFA)、股骨后髁角(posterior condylar angle,PCA)、胫骨旋转角(tibial rotation angle,TRA)与术前比较,差异均有统计学意义(P0.05)。术前11膝(16.42%)胫骨旋转力线不良,术后1周CT复查提示14膝(20.90%)胫骨假体旋转力线不良,不良发生率比较差异无统计学意义(χ2=0.443,P=0.506);术后胫骨假体内旋8°8膝(11.94%),外旋8°6膝(8.96%)。术后胫骨假体TRA与术前ATFA、胫骨平台TRA及术后PCA、ATFA均无相关性(r=—0.174,P=0.159;r=0.220,P=0.074;r=0.237,P=0.053;r=—0.095,P=0.442)。结论对于内翻型膝关节骨关节炎患者,采用Gemini MK-Ⅱ活动垫片膝关节假体行TKA时,采用胫骨结节内1/3解剖定位法易出现胫骨假体旋转不良。     

计算机导航辅助膝关节置换对股骨假体旋转力线是否存在优势

目的对比计算机导航辅助全膝关节置换(TKA)与传统TKA的近期疗效,探讨计算机导航辅助TKA对股骨假体旋转力线是否存在优势。方法将60例初次单侧TKA的患者随机分为导航组(30例)和传统组(30例),比较患者手术前后的股骨后髁轴(PCL)、前后轴(APL)、KSS评分、WOMAC评分、Oxford评分,对比两组的术后疗效及探讨假体旋转对线。结果患者均获得24个月随访。术后1、2、3、6、12、24个月两组KSS评分、WOMAC评分、Oxford评分比较差异均无统计学意义(P0.05)。术后3个月导航组PCL、APL与术前偏离的角度测量值分别为0.60°(0.40°,2.00°)、1.64°(0.30°,2.65°),传统组分别为1.22°(0.38°,2.89°)、2.03°(0.81°,2.53°);两组的PCL较术前偏离的角度比较差异有统计学意义(P=0.013),两组的APL较术前偏离的角度比较差异无统计学意义(P=0.198)。股骨匹配假体旋转位置在1°内的比例:导航组分别为PCL70%(21例)、APL 30%(9例),传统组分别为PCL 50%(15例)、APL 17%(5例)。结论计算机导航辅助TKA虽能获得更好的股骨假体旋转力线,但主要在后髁轴的对线上,且在术后1~24个月术后各时段3项评分上均无明显优势。     

全膝关节置换术后膝关节线改变与膝前痛的相关性

目的 探讨全膝关节置换术后膝关节线改变与膝前痛的相关性.方法 回顾性分析2008年1月至2010年12月因膝关节骨关节炎行初次全膝关节置换的76例患者的病例资料,男11例,女65例;年龄47～83岁,平均(68.88±7.61)岁.术中应用PFC后稳定型固定平台膝关节假体.术后每12个月定期门诊随访一次.根据Figgie膝关节线测量方法对术前及随访时的关节线进行测量,并计算术前、术后关节线的变化.关节线升高为正值,关节线降低为负值.采用Feller评分法评估术前及随访时的髌骨功能.评估术后24个月的关节线改变水平与Feller髌骨评分的相关性.结果 关节线改变-6.8～10.44 mm,平均(2.69±3.31) mm.随膝关节线升高,Feller髌骨评分呈下降趋势;关节线改变值与Feller髌骨评分呈负相关(r=-0.763,P=0.000).随关节线降低,Feller髌骨评分呈下降趋势;关节线改变值与髌骨评分呈正相关(r=0.914,P=0.000).术后12、24个月关节线改变4 mm以内的患者(55例)Feller髌骨评分均高于关节线改变大于4 mm的患者(21例),差异有统计学意义(t=12.648,P=0.000;t=11.775,P=0.000).结论 对后稳定型固定平台膝关节假体,关节线改变与膝前痛具有相关性,保持关节线变化在±4 mm以内有利于恢复膝关节功能.     

计算机辅助设计与3D打印个性化截骨导板辅助人工全膝关节置换术的精准度研究

目的探讨计算机辅助设计(CAD)与3D打印个性化截骨导板辅助的人工全膝关节置换术(TKA)的精准度及有效性。方法对32例膝关节骨性关节炎术前行患侧下肢全长CT扫描,将所获DICOM数据导入M3D软件中进行三维重建下肢全长,再进行计算机模拟截骨、假体安装、假体大小与位置测量,再基于CAD设计结果,采用3D打印制作个性化膝关节截骨导板。评估CAD设计的假体大小与术中实际假体大小的一致性。术后行患肢膝关节CT扫描并重建,比较术后实际所得的下肢冠状面髋-膝-踝(HKA)角、假体冠状面股骨组件(FFC)角、假体股骨假体旋转角(PCA)、假体冠状面胫骨组件角(FTC)、假体矢状面胫骨组件(LTC)角与术前CAD设计值的差异,测量股骨远端、胫骨平台截骨厚度的术前CAD设计值与手术实际值的差异。结果术前假体大小与术中使用完全一致31例,准确率96.9%;术前HKA偏差为(4.6±1.3)°,术后HKA偏差(3.0±1.2)°,差异有统计学意义(t=5.661,P0.01)。术前及术后所得HKA角、FFC角、PCA角、FTC角、LTC角与术前CAD设计值差异无统计学意义(P0.05)。术前股骨远端厚度(9.1±0.6)mm,术后股骨远端厚度(9.0±0.5),差异无统计学意义(t=1.402,P0.05)。术前胫骨截骨厚度(8.9±1.2)mm,术后胫骨截骨厚度(8.6±1.7)mm,差异无统计学意义(t=0.802,P0.05)。结论计算机辅助设计与3D打印个性化截骨导板辅助TKA术具有较高精准度,该方法可提供精准的TKA手术方案。     

TC-Dynamic后稳定型人工全膝关节系统术后近期疗效分析

目的探讨应用TC-Dynamic后稳定型人工全膝关节系统行全膝关节置换术(totalknee arthroplasty,TKA)的近期临床效果,评价其临床应用的可行性、安全性和有效性。方法2003年9月～2004年3月,应用TC-Dynamic人工全膝关节系统行TKA10例12膝(TC-Dynamic组),术前膝关节KSS(kneesocietyscore)评分为16.08±11.58分,功能评分为13.75±19.79分,膝关节活动度(rangeofmotion,ROM)为75.00±26.46°。同期使用Scorpio假体行TKA30例50膝(Scorpio组),术前膝关节KSS评分为19.48±9.67分,功能评分为3.16±19.82分,膝关节ROM为80.80±22.82°。比较两组患者术后疼痛缓解情况、KSS评分和功能评分改善情况,以及膝关节ROM的提高程度。结果所有患者术后获随访40～210d,平均130d。TC-Dynamic组术后KSS评分为88.83±4.04分,较术前改善72.75±14.47分,功能评分为79.17±5.15分,较术前改善65.42±19.47分;ROM为107.92±11.57°,较术前提高32.92±32.22°。Scorpio组术后KSS评分为85.68±7.36分,较术前改善66.20±10.44分,功能评分为71.40±12.70分,较术前改善68.24±25.35分;ROM为109.20±11.13°,较术前提高28.40±26.41°。术后各指标组间比较差异均无统计学意义(P>0.01)。两组患者术后X线片均示下肢力线良好,假体位置满意,无透亮线及任何松动迹象。结论TC-Dynamic后稳定型膝关节假体设计合理,术后近期效果良好;但远期疗效仍需大样本长期随访观察。TKA中正确的下肢力线、合理截骨和软组织平衡及屈曲伸直间隙平衡等,是获得良好临床效果和保证假体长期存活的关键。     

Kinematic comparison of posterior cruciate sacrifice versus substitution in a mobile bearing total knee arthroplasty

Interest in mobile bearing total knee arthroplasty (TKA) has increased significantly. The objective of this in vivo study was to analyze 2 different mobile bearing TKAs during gait and during a knee bend from 0 degrees to 90 degrees flexion. Femorotibial contact positions for 10 subjects, implanted by a single surgeon, were analyzed using videofluoroscopy. Five subjects were implanted with a posterior-stabilized mobile bearing TKA (PS), and 5 subjects were implanted with a posterior cruciate-sacrificing mobile bearing TKA (PCS). Each subject, while under fluoroscopic surveillance, performed 2 weight-bearing activities: i) normal gait and ii) deep-knee bend. This study showed that the kinematic patterns for subjects having either a PS or PCS mobile bearing TKA were similar during gait but different during a deep-knee bend. Subjects having a PS TKA experienced more posterior femoral rollback of the lateral condyle during the deep-knee bend. Findings of kinematic similarities in gait and differences in a deep-knee bend between these 2 mobile bearing designs are similar to previously published findings of fixed bearing posterior cruciate-retaining and PS TKA.     

膝骨关节炎患者股骨后髁软骨磨损差异对人工全膝关节置换术中股骨假体旋转定位的影响

目的通过测量膝骨关节炎患者股骨内、外侧后髁软骨厚度以及后髁角(posterior condylar angle,PCA),探讨其对人工全膝关节置换(total knee arthroplasty,TKA)术中截骨的影响。方法选择2011年5月-12月拟行TKA治疗的53例(60膝)膝骨关节炎患者作为研究对象(骨关节炎组),男12例(14膝),女41例(46膝);年龄57～82岁,平均71.9岁。胫股角为(183.2±2.6)°。以15例(30膝)健康志愿者膝关节作为对照(对照组),男6例,女9例;年龄59～68岁,平均66.3岁。将MRI扫描膝关节获得数据导入Mimics10.01交互式医学影像控制系统,测量内、外侧股骨后髁软骨厚度和包括与不包括后髁软骨时的PCA,进行统计学分析。结果对照组股骨内、外侧后髁软骨厚度分别为(1.85±0.33)mm及(1.92±0.27)mm,包括与不包括后髁软骨时的PCA分别为(5.0±0.9)°和(5.1±0.8)°,差异均无统计学意义(P>0.05)。骨关节炎组股骨内、外侧后髁软骨厚度分别为(0.45±0.40)mm及(1.78±0.51)mm,包括与不包括后髁软骨时的PCA分别为(3.3±1.7)°和(4.8±1.8)°,差异均有统计学意义(P<0.05)。骨关节炎组股骨内、外侧后髁软骨厚度差为(1.33±0.45)mm,与包括与不包括后髁软骨时的PCA角度差(1.5±1.3)°成正相关(r=0.75,P=0.01)。结论膝骨关节炎患者股骨后髁软骨磨损程度存在差异,导致内、外侧后髁软骨厚度和包括与不包括后髁软骨时的PCA存在差异,TKA术中行截骨时,应将股骨后髁软骨厚度差异纳入考虑范围内。     

Innex假体5年治疗结果:临床疗效及存活率分析

[目的]对使用Innex假体行全膝关节置换术(TKA)的患者行术后中期的影像学及临床随访,研究Innex 假体的临床疗效及存活率.[方法]对2003年9月～2005年12月使用后交叉韧带牺牲型Innex(Zimmer,Warsaw,Indiana)假体行TKA的88例(98膝)患者行平均5年的随访,回顾分析获得随访的74例(82膝)临床疗效及X线表现,通过问诊、查体、HSS评分进行临床评估,膝关节前后位、侧位X线片以及髌骨轴位X线片进行影像学评估,观察假体位置、关节线高度改变、胫骨平台后倾角、髌骨位置,有无假体松动、骨溶解.假体的存活率采用Kaplan -Meier分析,以任何原因所致的翻修为终点.[结果]患者术前的膝关节活动度平均91°(450～130°),随访时膝关节活动度平均108°(90°～132°);术前HSS评分为49分(18～86分),随访时提高到90分(54～98分).影像学评估显示假体位置良好,外翻角为5.6°,90.2%改变在3°内,关节线高度的改变为4.2mm(-15～14 mm),胫骨平台后倾角平均5.4°.所有的髌骨未出现错位、倾斜、半脱位.截至随访时,无1例因松动、骨溶解或其他原因翻修.[结论]Innex假体中期疗效良好,但仅可认为这是假体整个使用年限中的初步判断,长期效果仍需进一步随访.     

膝关节侧副韧带解剖特点与膝关节置换股骨假体旋转定位轴线的关系

目的分析股骨远端内、外侧侧副韧带起点及股骨内、外上髁轴线在全膝关节置换术(totalknee arthroplasty,TKA)中与股骨假体旋转角度的关系。方法对20只正常尸体膝关节标本进行解剖,经外上髁尖分别向内侧侧副韧带深、浅层起点钻孔,行MRI检查,测量矢状位像钻孔部位与内、外后髁几何圆心之间的距离及轴位像股骨髁后髁角(posteriorcondylarangle,PCA)和股骨髁扭转角(condylartwistangle,CTA)。结果内、外侧侧副韧带分浅、深两层,屈曲位深层紧张。PCA及CTA分别为4.50±1.26°及7.10±0.30°,二者差异有统计学意义(P<0.05),且均大于国外的相关报道。矢状位上,内侧后髁关节面圆弧半径为19.38±2.13mm,外侧为19.54±2.13mm,二者差异无统计学意义(P>0.05)。内侧侧副韧带股骨侧深层起点距股骨后髁几何圆心距离(d1)为4.22±0.20mm,较内上髁尖距后髁圆心的距离(d2)7.36±0.13mm小,且差异有统计学意义(P<0.05)。结论内、外后髁关节面的固定旋转轴心恰好通过内、外侧侧副韧带股骨侧深层起点,可以看作膝关节的屈曲固定轴,通过松解不同层面的侧副韧带,可以在TKA中针对性地松解软组织及调整伸屈间隙的平衡,从而矫正各种膝内、外翻及屈曲挛缩畸形。股骨内、外侧侧副韧带深层止点可作为TKA中股骨假体旋转定位的参考标志。     

Innex膝关节假体置换术后活动度与假体设计及手术技术的关系

目的 探讨Innex膝关节假体置换术后膝关节活动度与假体设计及手术技术的关系.方法 2003年9月至2005年12月使用CS型Innex假体行全膝关节置换88例(98膝),均患膝关节骨关节炎,体重指数20～30 kg/m2,内外翻畸形、屈曲畸形＜15°,为初次全膝关节置换并使用相同的手术技术.随访63例(70膝),随访时间4～6年,平均5.3年.分析活动度与股骨后髁偏心距和胫骨平台后倾角的相关性.根据术后、术前股骨后髁偏心距的差值大小将患者分为:1组,＜-2 mm;2组,-2～0 mm;3组,0～2 mm,4组,＞2 mm.分析各组术前体重指数、屈曲畸形、活动度、特种外科医院膝关节评分及术后活动度的差异.结果 随访患者术前膝关节活动度平均96.2°±11.9°,末次随访时平均109.8°±13.0°;术前股骨后髁偏心距平均(24.0±3.5)mm,术后平均(24.5±3.3)mm;术后胫骨平台后倾角平均5.5°±1.8°.膝关节活动度的差值与股骨后髁偏心距的差值相关,术后膝关节活动度与术后胫骨平台后倾角不相关.四组患者术前体重指数、屈曲畸形、活动度、特种外科医院膝关节评分差异无统计学意义,而术后活动度的差异有统计学意义.结论 Innex膝关节假体置换术后膝关节活动度良好.术中行股骨后方截骨时需注意恢复股骨后髁偏心距,以增加术后活动度.术后膝关节活动度与胫骨平台后倾角无关.

Abstract：

Objective To analysis the influence of component design and related surgical technique on knee range of motion (ROM) after total knee replacement using Innex knee system. Methods Between September 2003 and December 2005, 88 patients with 98 knees had consecutively undergone posterior cruciate-sacrificing TKA with Innex systems. The posterior condylar offset, post-operative tibial slope and knee ROM were measured in 63 patients (70 knees). The relationship of the change in posterior condylar offset and postoperative tibial slope with knee ROM was assessed using a scatterplot graph and Pearson's regression analysis. According to change of posterior condylar offset, which was measured by postoperative minus preoperative posterior condylar offset, patients were divided into 4 groups. The preoperative body mass index,flexion contracture, knee ROM, HSS score and the postoperative knee ROM of four groups were evaluated.Results The mean knee ROM had improved from 96.2°±11.9° preoperative to 109.8°±13.0° at final followup. The mean pre- and post-operative posterior condylar offset was (24.0±3.5) mm and (24.5±3.3) mm, respectively. The mean postoperative tibial slope was 5.5°±1.8°. There was statistical correlation between the difference in the posterior condylar offset and the change in knee ROM after TKA and no correlation between the postoperative tibial slope and knee ROM postoperatively. The preoperative body mass index, flexion contracture, knee ROM, HSS score did not show difference among four groups. There was a statistically difference in postoperative knee ROM among groups. Conclusion Restoration of posterior condylar offset is important to the maximum range of postoperative knee ROM when Orthopedic surgeons perform TKA with Innex systems.There was no correlation between the postoperative tibial slope and postoperative ROM.     

Functional comparison of posterior cruciate-retained versus cruciate-sacrificed total knee arthroplasty

Gait of 11 patients with bilateral paired posterior cruciate-retaining and cruciate-sacrificing total knee arthroplasties (TKA) was studied preoperatively and two years postoperatively on walking and stair climbing. Five-year clinical and roentgenographic examinations were included in the study. Differences between the two prostheses were noted both in level walking and in stair climbing. On level walking, cruciate-sacrificed TKA had more flexion in loading response and increased flexion and varus moments with increased muscle activity of quadriceps and biceps femoris. Abnormal gaits common to both types of knee were decreased flexion in stance and decreased single-limb stance. Both knees had a stiff-legged gait during stance. On stairs, the cruciate-sacrificed TKA substituted soleus muscle activity for knee stability. The single-limb stance and range of motion were similar for both knees. In clinical terms, the cruciate-sacrificed TKA is less efficient and has greater medial loading and higher joint reaction forces that may affect durability of the prosthesis. The five-year knee scores, patient satisfaction, and roentgenographic examinations were equal for both sets of knees.     

Range of motion after total knee arthroplasty The effect of implant design and weight-bearing conditions

Knee range of motion was determined in 60 patients to assess the effect of weight bearing on maximal knee flexion. Three patient subgroups were investigated: patients with normal knees, patients implanted with posterior cruciate-retaining (PCR) total knee arthroplasty (TKA), and patients implanted with posterior cruciate-substituting (PS) TKA. Maximal knee flexion was determined using videofluoroscopy both in a passive, non-weight-bearing mode and during active weight bearing. Flexion was diminished with weight bearing in all three subgroups (P < .045). Patients with normal knees exhibited significantly greater knee flexion than either TKA subgroup when measured either with or without weight bearing (P < .001). Knee flexion of both TKA subgroups was similar when measured passively without weight bearing. Patients with PS TKA demonstrated greater flexion than patients with PCR TKA when measured in weight bearing (P < .025), despite having less range of motion and lower clinical performance ratings preoperatively. Measurement of knee range of motion in a weight-bearing fashion may be a superior method of assessment of functional capabilities.     

膝内翻全膝关节置换术软组织平衡方法探讨

目的分析骨性关节炎膝内翻角度的组成,探讨全膝关节置换术(totalkneearthroplasty,TKA)中软组织平衡方法。方法分析1999年1月～2003年12月因骨性关节炎行TKA的100例145侧膝内翻患者,其中男18例25个膝关节,女82例120个膝关节。平均年龄62.4岁(45～80岁)。膝关节HSS(hospitalofspecialsurgery)评分38.0±3.2分。根据下肢力线情况准确截骨,恢复膝关节静态骨性对线,然后根据内翻角度组成情况决定软组织松解部位及范围。软组织松解分3步进行,即截骨前暴露时松解、截骨时松解和截骨后安装假体前彻底松解。松解要点包括:韧带及关节囊松解、骨赘清除及髌骨外侧支持带松解。结果术前膝内翻总角度为9.2±3.1°,软组织失衡性内翻占53.2%,胫骨结构性内翻占46.8%,二者差异无统计学意义(P>0.05)。胫骨结构性内翻中胫骨骨性内翻占22.8%,胫骨平台关节面磨损及破坏占24.0%。术后结果表明,平均胫骨平台截骨角度为4.3°,占膝内翻矫正度数的27.9%;软组织平衡术矫正的度数为10.7°,占膝内翻矫正度数的72.1%。术后HSS评分为87.0±4.5分,与术前比较差异有统计学意义(P<0.05)。结论骨性关节炎膝内翻角度由两方面组成:即胫骨结构性内翻和膝关节侧副韧带及软组织失衡导致的内翻。其中后者占膝内翻角度的主要部分,通过松解内侧软组织进行矫正,松解的关键部位为内侧侧副韧带胫骨侧止点及后关节囊。松解时应循序渐进,随时测试,且勿松解过度。     

Kinematics of medial osteoarthritic knees before and after posterior cruciate ligament retaining total knee arthroplasty

Total knee arthroplasty (TKA) is a widely accepted surgical procedure for the treatment of patients with end‐stage osteoarthritis (OA). However, the function of the knee is not always fully recovered after TKA. We used a dual fluoroscopic imaging system to evaluate the in vivo kinematics of the knee with medial compartment OA before and after a posterior cruciate ligament‐retaining TKA (PCR‐TKA) during weight‐bearing knee flexion, and compared the results to those of normal knees. The OA knees displayed similar internal/external tibial rotation to normal knees. However, the OA knees had less overall posterior femoral translation relative to the tibia between 0° and 105° flexion and more varus knee rotation between 0° and 45° flexion, than in the normal knees. Additionally, in the OA knees the femur was located more medially than in the normal knees, particularly between 30° and 60° flexion. After PCR‐TKA, the knee kinematics were not restored to normal. The overall internal tibial rotation and posterior femoral translation between 0° and 105° knee flexion were dramatically reduced. Additionally, PCR‐TKA introduced an abnormal anterior femoral translation during early knee flexion, and the femur was located lateral to the tibia throughout weight‐bearing flexion. The data help understand the biomechanical functions of the knee with medial compartment OA before and after contemporary PCR‐TKA. They may also be useful for improvement of future prostheses designs and surgical techniques in treatment of knees with end‐stage OA. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:40–46, 2011