半伸直位髌上入路髓内钉治疗胫骨骨折

目的： 探讨膝关节半伸直位髌上入路胫骨髓内钉治疗胫骨骨折的临床疗效。方法： 回顾性分析2018年1月至2019年6月采用髌上入路胫骨髓内钉治疗的胫骨骨折患者23例,男18例,女5例;年龄26~67（38.5±9.6）岁。其中胫骨近端骨折8例,胫骨中段骨折7例,胫骨远端骨折6例,胫骨多段骨折2例。记录患者的手术时间、术中出血量、术后并发症、骨愈合时间,比较术后3 d与术后3个月膝关节活动范围及膝关节疼痛视觉模拟评分（visual analogue scale,VAS）,术后6个月采用膝关节美国特种外科医院（Hospital for Special Surgery,HSS）评分进行临床疗效评价。结果： 所有患者获得随访,时间8~19（12.3±7.6）个月。手术时间50~85（55.3±5.1） min,出血量50~150（84.0±8.7） ml。无明显围手术期并发症发生。所有骨折获得Ⅰ期骨愈合,骨愈合时间3~8（4.6±1.5）个月。膝关节屈伸活动范围由术后3 d的（110.4±15.3）°提高至术后3个月的（123.7±16.5）°,差异有统计学意义（t=6.57,P<0.001）;术后3 d膝关节VAS评分（0.22±0.74）分与术后3个月（0.04±0.20）分比较差异无统计学意义（t=1.09,P>0.05）。术后6个月膝关节HSS评分为（86.2±11.5）分,其中优19例,良4例。结论： 膝关节半伸直位髌上入路胫骨髓内钉治疗胫骨骨折,操作简便,对软组织损伤小,膝关节疼痛率低,术后患肢功能恢复快,并发症少,对于胫骨多段骨折及合并同侧下肢多发骨折的患者尤其适用,是一种简便、安全有效的手术方法。     

个体化设置股骨开髓点与外翻角在股骨外弓患者人工全膝关节置换术中的应用

目的：探讨外移股骨开髓点并设置个性化股骨外翻角能否改善合并股骨外弓的人工全膝关节置换术（total knee arthroplasty,TKA）患者下肢力线。方法：2016年3月至2018年10月,收治50例（55膝）合并股骨外弓拟行TKA的膝内翻畸形的骨关节炎患者。男10例,女40例;年龄63.1~80.5（67.8±5.8）岁。单侧45例,双侧5例。55膝的骨关节炎分期均为Kellgren-Lawrence分级Ⅲ-Ⅳ级,病程2~10年。术前特种外科医院（Hospital for Special Surgery,HSS）评分疼痛（15.20±3.52）分,功能（8.30±2.96）分,活动度（10.15±2.85）分,肌力（4.20±1.95）分,屈曲畸形（5.50±3.05）分,稳定性（6.15±2.20）分,总分（47.93±3.39）分。股骨外弓角6.4~16.7（10.63±2.29）°,胫股角7.4~12.6（12.04±3.59）°,解剖股骨远端外侧角83.10~91.20（84.55±1.66）°,膝关节中心至下肢力线距离2.01~6.00（3.57±1.12） cm。置换术中均通过个性化设置股骨开髓点与外翻角,获得良好下肢力线。结果：术前股骨开髓点外移距离0.24~0.74（0.54±0.10） cm,股骨内外髁间距离6.86~8.12（7.27±0.27） cm。术前股骨外翻角（valgus correction angle,VCA）7.20~13.80（9.38±1.38）°;矫正后VCA''6.10~9.50（7.36±0.82）°。50例患者均获随访,时间3~36（13.5±5.8）个月。术后患者均获得良好的膝关节功能,术后3个月HSS评分疼痛（25.30±3.05）分,功能（18.25±2.05）分,活动度（16.05±0.75）分,肌力（6.20±2.10）分,屈曲畸形（8.80±1.85）分,稳定性（8.20±1.75）分,总分90.00~93.00（91.82±0.98）分,总分较术前提高（t=1.728,P=0.038）。术后X线片复查示,假体没有松动、下沉及骨溶解等征象发生;术后第2天负重位X线片上胫股角1.30~4.90（2.53±0.83）°,解剖股骨远端外侧角87.50~91.30（88.73±0.86）°,膝关节中心至下肢力线距离0.02~1.20（0.23±0.05） cm,均较术前改善（t=2.415,P=0.019;t=1.496,P=0.041;t=1.912,P=0.033）。结论：合并股骨外弓的TKA中通过外移股骨开髓点并设置个性化股骨外翻角能获得良好的下肢力线和膝关节功能。     

应用双髋关节正位X线片评估全髋关节置换术后髋臼前倾角

目的: 探讨是否可以在普通双髋关节正位X线片上评估髋臼假体前倾角。方法: 2019年3月至7月收治全髋关节置换术后患者32例(共41髋),男18例,女14例,年龄(66.2±4.1)岁,所有患者于术后完成双髋关节正位X线片及骨盆CT平扫。通过骨盆CT平扫测量髋臼前倾角,在X线片上采用Saka等测量公式进行测量。结果: 41髋X线片测量髋臼前倾角为(16.2±5.0)°,与CT测量的髋臼前倾角(31.8±9.7)°间差异有统计学意义(P=0.00)。此外,X线片测量与CT测量的髋臼前倾角具有明显相关性(Pearson相关系数r=0.84,P=0.00)。结论: CT可以较准确地测得髋臼前倾角,但是其存在辐射量大、成本较高、假体CT伪影重等明显弊端。在普通双髋关节正位X线片上采用Saka测量公式虽然无法像CT测量一样直接获得准确的髋臼前倾角,但却和CT测得的髋臼前倾角间存在高度的相关性,所以提出的方法也可以初步评估髋臼前倾角。     

髌上入路胫骨髓内钉治疗胫骨近端骨折

目的:探讨膝关节半伸直位髌上入路胫骨髓内钉治疗胫骨近端骨折的临床疗效。方法:2013年1月至2014年1月共收治胫骨近端骨折16例,男14例,女2例;年龄26～57岁,平均42.2岁。所有患者为单侧闭合骨折,采用膝关节半伸直位髌上入路META-NAIL胫骨髓内钉内固定治疗。记录手术时间、术后并发症、骨愈合时间、胫骨力线和膝关节活动范围,并采用视觉模拟评分法(visual analogue scale,VAS)和Lysholm膝关节评分评定手术疗效。结果:所有16例患者手术时间65～95 min,平均(75.7±8.3) min.无明显围手术期并发症发生。所有患者获随访,时间12～24个月,平均(15.6±8.1)个月。15例获得Ⅰ期骨愈合,平均骨愈合时间(3.6±1.8)个月(3～5个月).末次随访时,所有患者胫骨力线良好,无膝前疼痛。患侧膝关节屈伸活动范围平均(124.4±18.8)°,健侧(127.5±16.7)°。Lysholm膝关节评分77～92分,平均86.4±12.3.结论:膝关节半伸直位髌上入路胫骨髓内钉治疗胫骨近端骨折,术中复位及固定操作方便,术后并发症少,患肢功能恢复良好,临床疗效满意。     

关节镜下单通道双线技术治疗胫骨髁间棘骨折

目的:探讨关节镜下单通道双线技术治疗胫骨髁间棘骨折的临床疗效。方法:2016年1月至2020年4月,收治22例胫骨髁间棘骨折患者,男14例,女8例;年龄26~45(34.8±5.9)岁;手术时间为受伤后5~15(11.2±4.1) d。所有患者给予关节镜下骨块复位和单通道双线技术固定。术后根据X线片评估骨折愈合情况,术前及末次随访采用Lysholm评分、IKDC 2000评分和抽屉试验进行临床疗效评价。结果:22例患者全部获得随访,时间12~75(34.6±13.0)个月。Lysholm评分术前(30.80±9.55)分,末次随访(89.60±2.89)分,差异有统计学意义(t=9.67,P<0.01);IKDC 2000术前(24.60±7.21)分,末次随访(80.00±6.17)分,差异有统计学意义(t=11.41,P<0.01)。1例患者抽屉试验为弱阳性。结论:单通道双线技术可实现对髁间棘撕脱骨块的有效固定,操作简便、创伤小,适用于各种类型的髁间棘撕脱骨折。目的:探讨关节镜下单通道双线技术治疗胫骨髁间棘骨折的临床疗效。方法:2016年1月至2020年4月,收治22例胫骨髁间棘骨折患者,男14例,女8例;年龄26~45(34.8±5.9)岁;手术时间为受伤后5~15(11.2±4.1) d。所有患者给予关节镜下骨块复位和单通道双线技术固定。术后根据X线片评估骨折愈合情况,术前及末次随访采用Lysholm评分、IKDC 2000评分和抽屉试验进行临床疗效评价。结果:22例患者全部获得随访,时间12~75(34.6±13.0)个月。Lysholm评分术前(30.80±9.55)分,末次随访(89.60±2.89)分,差异有统计学意义(t=9.67,P<0.01);IKDC 2000术前(24.60±7.21)分,末次随访(80.00±6.17)分,差异有统计学意义(t=11.41,P<0.01)。1例患者抽屉试验为弱阳性。结论:单通道双线技术可实现对髁间棘撕脱骨块的有效固定,操作简便、创伤小,适用于各种类型的髁间棘撕脱骨折。     

胫骨前嵴作为全膝关节置换术胫骨假体旋转对位解剖参考的可靠性研究

目的:通过CT测量正常膝关节探讨胫骨前嵴作为全膝关节置换术(total knee arthroplasty,TKA)胫骨旋转对线参考的可靠性。方法:自2017年7月至2018年6月选择122例因下肢创伤行CT血管造影(computed tomography angiography,CTA) 检查的患者,其中男 89 例,女 33 例;年龄 18 ～ 81 (51.4±16.4) 岁。使用影像归档和通信系统(picture archiving and communication system,PACS)标记健侧正常膝关节的外科通髁线(surgical epicondylar axis,SEA),外侧平台远端8 mm平面的髌韧带内侧缘与后叉韧带胫骨止点中点的连线(髌韧带内侧缘轴),胫骨横轴,髌韧带止点与后叉韧带胫骨止点中点投影的连线(Akagi线),髌韧带止点中内1/3与后叉韧带胫骨止点中点投影的连线(髌韧带止点中内1/3轴),胫骨结节中内1/3与后叉韧带胫骨止点中点投影的连线(Insall线),胫骨结节内侧缘与后叉韧带胫骨止点中点投影的连线(胫骨结节内侧缘轴)。把前缘锐利的胫骨前嵴等分为3部分,取上下顶点和中间2个点,标记4个点在该平面与与后叉韧带胫骨止点中点投影的连线(胫骨前嵴近端轴、胫骨前嵴中段轴1、胫骨前嵴中段轴2以及胫骨前嵴远端轴)。测量胫骨横轴和SEA之间以及其他各轴与SEA垂线的角度。对比10个胫骨轴之间的两两关系。结果:髌韧带内侧缘轴、胫骨前嵴近端轴、胫骨前嵴中段轴1、胫骨前嵴中段轴2、胫骨前嵴远端轴、Akagi线、髌韧带止点中内1/3轴、Insall线、胫骨结节内侧缘轴与SEA垂线的角度分别为(-1.6±4.5)°、(12.0±6.9)°、(7.2±8.6)°、(7.1±10.4)°、(6.6±13.5)°、(1.4±5.0)°、(10.2±5.1)°、(11.9±5.4)°和(3.6±4.8)°。胫骨横轴与 SEA 的夹角为(4.1±5.3)°。髌韧带内侧缘轴相对于SEA外旋,Insall线、髌韧带止点中内1/3轴和胫骨前嵴近端轴明显大于Akagi线、胫骨横轴、胫骨结节内侧缘轴(P0.001)。胫骨前嵴中段轴1和2以及胫骨前嵴远端轴明显大于Akagi线、胫骨横轴、胫骨结节内侧缘轴(P0.001)。但是胫骨前嵴中段轴1和2以及胫骨前嵴远端轴小于Insall线、髌韧带止点中内1/3轴和胫骨前嵴近端轴(P0.01)。胫骨前嵴中远段3个轴间比较差异无统计学意义(P0.05)。结论:胫骨前嵴中段可以作为TKA胫骨假体旋转对线参考一个选择,其可靠性优于Insall线,但要差于Akagi线、胫骨横轴和胫骨结节内侧缘轴。     

应用经髌上入路交锁髓内钉技术治疗胫骨骨折

目的：探讨应用经髌上入路交锁髓内钉技术治疗胫骨骨折的短期疗效。方法：2016年1月至2018年6月采用交锁髓内钉手术治疗80例胫骨骨折患者,根据手术入路不同分为观察组（经髌上入路）和对照组（经髌韧带入路）。其中观察组40例,男28例,女12例,年龄28~67（46.70±10.34）岁;对照组40例,男30例,女10例,年龄31~69（49.38±10.74）岁。记录并比较分析两组患者手术时间,切口长度,术中X线机透视次数,术中失血量,骨折愈合时间,术后主动直腿抬高（straight leg raise,SLR）时间,住院时间,膝痛视觉模拟评分（visual analogue scale,VAS）,膝关节疼痛率,术后美国特种外科医院（Hospital for Special Surgery,HSS）膝关节评分等指标。结果：全部病例获得随访,时间19~38（24.60±4.52）个月。观察组手术时间（53.83±7.01） min,切口长度（3.98±0.83） cm,术中X线机透视次数（18.90±1.75）次,骨折愈合时间（10.03±0.89）周,术后SLR时间（1.19±0.25） d,住院时间（6.73±1.06） d均优于对照组（P<0.05）。末次随访,根据HSS评分评估疗效,观察组优34例,良5例,可1例,差0例;对照组优25例,良9例,可6例,差0例;观察组疗效优于对照组（P<0.05）。结论：采用经髌上入路交锁髓内钉内固定治疗胫骨骨折,具有创伤小、膝关节功能恢复更好等优点,可获得更加满意的临床效果,可进一步广泛应用。     

固定平台与旋转平台假体用于外翻膝的早期疗效观察

目的:比较外翻膝人工全膝关节置换术应用旋转平台和固定平台两型假体的早期临床疗效。方法:选取2011年1月至2013年12月吉林大学第一医院骨关节外科由同一医师进行初次人工膝关节置换的17例(23膝)进行回顾性随访研究,其中男2例,女15例;年龄48～75岁,平均61.5岁。术前诊断为骨性关节炎14例(19膝),类风湿性关节炎3例(4膝),所有膝关节有外翻畸形。其中9例(12膝)使用固定平台型假体(PFC Sigma),8例(11膝)使用旋转平台型假体(PFC Sigma RP).术前和术后随访行KSS、HSS、WOMAC评分,测量关节活动度、胫股角等指标,进行统计学分析。结果:所有患者获随访,时间6～36个月,平均25个月。两组患者膝外翻畸形均得到矫正,术后末次随访的KSS、HSS、WOMAC评分及膝关节活动度、胫股角较术前明显改善(P<0.01).其中固定平台组和旋转平台组在术后KSS、HSS、WOMAC评分以及胫骨角、膝关节活范围改善度方面比较,差异无统计学意义(P>0.05);而术后末次随访膝关活动范围固定平台组(101.8±8.8)°与旋转平台组(108.4±7.2)°差异有统计学意义(P<0.05).旋转平台组没有发现垫片脱位,两组术后均无感染、腓总神经麻痹、脱位、膝关节不稳等并发症发生,X线检查未见假体骨溶解及松动发生。结论:外翻膝人工全膝关节置换术使用旋转平台和固定平台型假体均能获得满意的早期临床效果,两者的近期临床疗效比较无明显差异。     

骨保留型股骨柄假体在年轻患者Dorr C型股骨髓腔中的应用

目的：探讨应用Tri-lock生物短柄假体在年轻患者Dorr C型髓腔进行人工全髋关节置换的近期临床疗效。方法：2010年1月至2014年1月采用Tri-Lock BPS假体行全髋关节置换术治疗烟囱状股骨髓腔年轻患者35例（37髋），男18例（20髋），女17例（17髋）；年龄21.2～38.5（32.2±3.0）岁。类风湿髋关节炎16例17髋，类风湿关节炎8例9髋，股骨头无菌性坏死11例11髋。所有病例合并不同程度的骨质疏松，按Singh指数分级：Ⅲ级26例，Ⅱ级9例。髋臼全部采用生物型假体，均采用陶瓷内衬，股骨头采用全陶瓷头。正位X线片上股骨近段髓腔形态均为Dorr C型，置换术后行X线检查评估假体柄位置，Engh标准评价骨-假体界面稳定性，Harris评分标准评价髋关节功能，并统计比较术前和末次随访时的髋关节活动度变化。结果：全部病例获得随访，随访时间18～45个月，平均33.8个月。35例（37髋） Harris髋关节评分由术前51.2～73.5（61.8±3.0）分提高至末次随访时92.5～98.8（93.3±6.5）分，差异有统计学意义（t=54.745，P<0.01）。髋关节活动度由术前0～55（46.5±8.0）°提高到末次随访时的85～130（101.2±10.5）°，差异有统计学意义（t=133.091，P<0.01）。术后即刻X线片均显示股骨短柄假体与髓腔紧密压配，末次随访时37髋均有明显股骨骨皮质增厚；22髋有不同程度股骨近端应力遮挡性骨吸收，其中Ⅰ度（股骨距密度低，且变圆钝）12髋，Ⅱ度（累及小转子）10髋。15髋有明显股骨骨皮质增厚，无大腿痛发生。结论：锥形柄短柄化的Tri-Lock生物短柄可良好充填Dorr C型烟囱状髓腔并有效保留良好的股骨近端骨量，表面钛微孔涂层可有效增加假体摩擦力，短小的柄端在髓腔内的指向作用可有效避免髋内外翻的发生。     

膝关节骨关节炎患者胫骨前后轴的测量与临床意义

目的 测定健康人膝关节胫骨前后轴（anterioposterior axis,AP轴）的解剖学标志,比较膝关节骨关节炎患者合并内翻或外翻畸形的情况下,胫骨前后轴的位移趋势,并判断如果以胫骨结节内1/3作为旋转定位参考点情况下,胫骨假体相对于胫骨前后轴的旋转匹配程度.方法 选择32位膝关节骨关节炎患者,共62个膝关节进行膝关节旋转中立位CT扫描,并以10个正常膝关节作为对照,分别测量在胫骨平台层面及髌腱附着点层面,胫骨AP轴与髌腱交点内侧宽度平均比例;胫骨AP轴与PCL中点-髌腱内缘连线角度及其与PCL中点与髌腱内1/3连线之间的角度.结果 在髌腱附着点层面,正常膝关节胫骨AP轴和PCL胫骨附着点中点与髌腱内侧缘连线成角约0.57°±5.63°,胫骨AP轴与髌腱交点内侧比例为0.54%±18.63%;在膝关节骨关节炎合并内翻或外翻畸形情况下,胫骨AP轴与髌腱交点内侧所占比例明显增加（P＜0.05）,合并内翻或外翻畸形的骨关节炎膝关节,胫骨AP轴和PCL中点与髌腱内缘连线夹角增加,PCL中点与髌腱内1/3连线和胫骨AP轴的角度在外旋8.左右.结论 健康人胫骨AP轴总体为PCL中点与髌腱内侧缘连线,骨关节炎合并内翻或外翻畸形情况下,胫骨AP轴相对于PCL中点与髌腱内侧缘连线呈外旋趋势,如果以胫骨结节内1/3作为胫骨假体旋转定位参考点,胫骨假体相对于胫骨前后轴具有外旋倾向.     

胫骨冠状面弯曲导致全膝关节置换术后胫骨假体力线不良

目的:探讨行全膝关节置换术(total knee arthroplasty,TKA)患者中胫骨冠状面弯曲对胫骨假体对线的影响.方法:自2019年7月至2021年4月,选取全膝关节置换术治疗的100例膝关节骨性关节炎患者,术前摄下肢全长X线片并测量胫骨冠状面弯曲角度(tibial bowing angle,TBA),TB...     

Evaluation of the rotational alignment of the tibial component in total knee arthroplasty: position prioritizing maximum coverage

Background

The standard for rotational alignment of the tibial component in total knee arthroplasty (TKA) remains unclear. Cases often require positioning of the tibial component, prioritizing adequate coverage of resected bone surface rather than alignment with the tibial rotational axis. We investigated tibial component position in TKA, prioritizing maximum coverage of resected bone surface, and evaluated the correlation with the tibial anteroposterior (AP) axis.

Methods

We analyzed preoperative computed tomography images for primary TKA in 106 cases and 157 knees, using three-dimensional planning software. Tibial component position prioritizing maximum coverage of resected bone surface was simulated, and results were compared with the AP axis. Rotational alignment angle was defined as that between a line perpendicular to the tibial AP axis and a line connecting the posterior edge of the tibial component.

Results

The simulated tibial component was more externally rotated by a mean 4.5° ± 4.2°. The alignment angle showed normal distribution, but variability was large, ranging from 5.1° internal rotation to 16.2° external rotation. In 138 of 157 (87.9 %) knees, the tibial component was positioned in the externally rotated position with respect to the AP axis. The tibial component was aligned within the medial one-third of the patellar tendon in 122 of 157 (77.7 %) knees.

Conclusions

The tibial component aligned using coverage prioritizing was externally rotated, although large variability was observed. Rotational alignment was optimal in 79 % of cases when the tibial component was aligned with coverage prioritizing, but hyperexternal rotation was observed in patients with severe knee deformation.

     

Tibial Tubercle-Trochlear Groove Distance Influences Patellar Tilt After Total Knee Arthroplasty

BackgroundTibial tubercle-trochlear groove (TT-TG) distance is associated with a greater risk of recurrent patellar dislocation in young, active patients. However, the effect of TT-TG distance after total knee arthroplasty (TKA) has not been investigated. The purpose is to analyze the effect of TT-TG distance and component rotation on patellar tilt and patellar shift after TKA.MethodsAfter TKA, axial computed tomography scans and axial radiograph were taken in 115 consecutive knees. TT-TG distance was measured between the most anterior point of the tibial tuberosity and the deepest point of the femoral component relative to a line connecting the anterior condyles. Femoral and tibial component rotation was measured relative to the femoral and tibial rotational axis, respectively. Pearson correlation coefficients were calculated.ResultsTT-TG distance had a significant correlation with patellar tilt in extension (R = 0.220, P = .018), patellar tilt in flexion (R = 0.438, P < .001), and patellar shift (R = 0.330, P < .001). Tibial component rotation had a significant correlation with patellar tilt in flexion (R = −0.251, P = .007) and patellar shift (R = −0.360, P < .001). Femoral component rotation had no significant correlations. Tibial component rotation had a significant correlation with TT-TG distance (R = −0.573, P < .001), whereas femoral component rotation had no correlation (P = .192).ConclusionTT-TG distance had a significant correlation with patellar tilt and patellar shift. Surgeons need to understand the factors affecting TT-TG distance and to pay attention to avoiding excessive TT-TG distance after TKA.     

Intraoperative Tibial Anteroposterior Axis Could Not Be Replicated After Tibial Osteotomy in Total Knee Arthroplasty

BackgroundWe evaluated the effect of the anteroposterior (AP) axis of the proximal tibia defined at the cutting surface using an image-free navigation system in total knee arthroplasty.MethodsThis prospective study included 68 patients (79 knees) who underwent total knee arthroplasty. The tibial AP axis was registered in the navigation system with reference to Akagi’s line, connecting the middle of the posterior cruciate ligament to the medial border of the patellar tendon attachment at the tibial joint surface. After proximal tibial osteotomy, the AP axis was replicated as the AP(O) axis. We measured the difference between the AP axis defined at the joint surface and the AP(O) axis defined at the osteotomy surface.ResultsThe AP(O) axis at the osteotomy surface internally rotated 2.0° to the AP axis at the joint surface, and the AP(O) axis outlier (difference to AP axis: >3°) occurred in 54% (43 knees). In the >3° malrotation group, internal malrotation occurred in 37% (30 knees) and external malrotation occurred in 17% (13 knees). In the outlier analysis, the left knees were significantly found in the internal outlier group.ConclusionThe tibial AP axis, connecting the middle of the posterior cruciate ligament to the medial border of the patellar tendon attachment defined at the tibial joint surface, could not be replicated at the tibial osteotomy surface. If the tibial components were set depending only on the AP axis defined at the osteotomy surface, the tibial components could internally rotate and have more outliers, especially in the left knees.     

Antero-posterior axis of tibia in patient undergoing total knee replacement in Indian population

IntroductionAim of this CT- based study was to find out a reliable anatomical axis for proper rotational placement of the tibial component during knee replacement surgery in the Indian population.Material and methodsCT scanning was performed pre-operatively on all the 45 patients (13 men, 32 women, total 68 knees) due to undergo knee replacement for osteo-arthritic knees. The tibial anteroposterior (AP) axis is defined as a line drawn perpendicular to the surgical epicondylar femoral axis and passing through the center of posterior cruciate ligament (PCL) attachment. Angles between various anatomic landmarks and the defined tibial AP axis were identified.ResultsThe mean angle between line connecting the medial border of patellar tendon and centre of PCL and the defined tibial AP axis was 0.06 (−5 to 7; SD 2.65) and was closest to defined AP axis of tibia. This axis remained the closest irrespective of the varying femoro-tibial angle and severity of tibial bowing.DiscussionIn our patients, the line connecting the medial border of patellar tendon to the centre of the PCL has been found to be an independent, reliable and reproducible rotational axis for placing the tibial trial and definitivite prosthesis. This is particularly helpful for those surgeons, who prepare the femur earlier than the tibial cut and trial.ConclusionThis tibial AP axis along with other anatomical landmarks is a reliable and reproducible landmark for implanting the tibial prosthesis in a proper rotational alignment in the Indian population.     

Measurement of rotational alignment of the distal femur in total knee arthroplasty

Objectives: To measure and compare the included angle between the surgical transepicondylar axis (STEA) and the posterior condylar line (PCL) and the included angle between the femoral anteroposterior line (APL) and PCL, and to discuss the value of STEA, APL, and PCL as rotational alignment landmarks of the distal femur in total knee arthroplasty (TKA). Methods: Seventy‐five normal femoral specimens from Chinese adult cadavers were randomly selected. An axial photograph of every femoral specimen was taken with a digital camera and put into a personal computer. Using Photoshop 7.0.1 software, the included angle between the perpendicular line of APL and the PCL, noted as APA, together with the posterior condylar angle (PCA) between STEA and PCL were measured and compared using a paired‐samples t‐test. Results: The value for PCA was 3.67°± 1.62° (range, 0.75°–5.90°) and for APA 3.50°± 1.40° (range, 1.34°–5.65°). There was no significant difference between these two angles (t= 0.949, P= 0.359). Considering their relatively small means, these two angles showed wide variations. Conclusions: The rotational alignment of the femoral component can not accurately be determined by using PCL as a landmark. In order to get a proper rotational alignment of the femoral component in most cases of TKA, APL and STEA should be used as a double check.     

The influence of component alignment on patellar kinematics in total knee arthroplasty

Background and purpose — Postoperative anterior knee pain is one of the most frequent complications after total knee arthroplasty (TKA). Changes in patellar kinematics after TKA relative to the preoperative arthritic knee are not well understood. We compared the patellar kinematics preoperatively with the kinematics after ligament-balanced navigated TKA.

Patients and methods — We measured patellar tracking before and after ligament-balanced TKA in 40 consecutive patients using computer navigation. Furthermore, the influences of different femoral and tibial component alignment on patellar kinematics were analyzed using generalized linear models.

Results — After TKA, the patellae shifted statistically significantly more laterally between 30° and 60°. The lateral tilt increased at 90° of flexion whereas the epicondylar distance decreased between 45° and 75° of flexion. Sagittal component alignment, but not rotational component alignment, had a significant influence on patellar kinematics.

Interpretation — There are major differences in patellar kinematics between the preoperative arthritic knee and the knee after TKA. Combined sagittal component alignment in particular appears to have a major effect on patellar kinematics. Surgeons should be especially aware of altering preoperative sagittal alignment until the possible clinical relevance has been investigated.     

机器人辅助人工全膝关节置换与传统手术临床效果比较的Meta分析

目的：通过Meta分析比较机器人辅助全膝关节置换术和传统全膝关节置换术效果的差异,以明确机器人辅助全膝关节置换术是否可提供更好的假体下肢力线及临床预后。方法：计算机检索建库至2018年11月Embase、Pubmed、Web of Science数据库和中国期刊全文数据库（CNKI）、万方数据库、维普中文科技期刊数据库（VIP）,查找比较机器人辅助和传统全膝关节置换术效果差异的临床对照研究。根据纳入与排除标准进行文献筛选、质量评价及数据提取后,应用Revman 5.3软件对文献数据进行Meta分析。结果：共纳入6篇临床对照研究,机器人辅助全膝关节置换术组253例,传统全膝关节置换术组231例。Meta分析结果：机器人辅助TKA组在下肢冠状位力线角度[WMD=-1.00,95%CI（-1.66,-0.35）,P=0.003],下肢冠状位力线内翻或外翻>3°发生率[RR=0.04,95%CI（0.01,0.13）,P=0.000 01]方面优于传统全膝关节置换术组;但两组膝关节活动范围[WMD=0.06,95%CI（-5.43,5.55）,P=0.98],正位片胫骨角[WMD=-0.19,95%CI（-0.81,0.43）,P=0.55]与侧位片胫骨角[WMD=-1.37,95%CI（-3.73,0.99）,P=0.25],正位片股骨角[WMD=0.30,95%CI（-1.37,1.96）,P=0.72]与侧位片股骨角[WMD=-0.93,95%CI（-1.98,0.12）,P=0.08],并发症发生率[RR=0.84,95%CI（0.45,1.58）,P=0.60]比较,差异无统计学意义。机器人辅助TKA组手术时间长于传统TKA组[WMD=14.28,95%CI（0.79,27.77）,P=0.04]。结论：在全膝关节置换术中使用机器人辅助系统可明显提高假体固定精度,更好地重建下肢力线,并有减轻患者术后疼痛、促进膝关节功能恢复的潜在优势。受纳入文献数量与质量的限制,未来仍需长期随访的高质量随机对照研究对本文结论加以佐证。     

全膝关节置换术的假体旋转不良的CT分析

目的应用CT技术测量全膝关节置换术股骨假体和胫骨假体旋转角度,探讨假体旋转性和髌股关节并发症之间的关系。方法以股骨髁上轴和胫骨结节为参考点,对股骨假体和胫骨假体的旋转角度进行测量,并比较了20例功能良好膝关节和30例产生髌股关节并发症的膝关节的假体旋转性。结果髌股关节并发症组的假体存在过度内旋,其内旋度数和值与髌股关节并发症的严重程度成正相关。轻度假体内旋(1°～4°)导致髌骨倾斜和轨迹外移;中度假体内旋(3°～8°)导致髌骨半脱位;重度假体内旋(7°～17°)导致早期的髌骨脱位和晚期的髌骨置换失败。功能良好组的假体外旋10°～0°。结论在机械轴线正常时,假体的内旋放置可能是导致髌股关节并发症的主要原因;利用CT扫描图像,行假体旋转度测量可用于术中以指导手术,术后也可以作为是否需要翻修的评价指标。