比较固定平台和高屈曲旋转平台假体人工膝关节置换术治疗膝骨性关节炎的效果

目的比较固定平台和高屈曲旋转平台假体人工膝关节置换术治疗膝骨性关节炎(OA)的效果。方法回顾性分析2016-10—2018-10间在新乡市第二人民医院接受人工膝关节置换术治疗的176例膝OA患者的资料。按不同假体分为2组,各88例。固定组采用固定平台假体,旋转组采用高屈曲旋转平台假体。比较2组术前,术后6个月、12个月膝关节功能(HSS)评分、膝关节活动度(ROM)、并发症发生率。结果 2组并发症发生率差异无统计学意义(P0.05)。术后12个月旋转组HSS评分、ROM均高于固定组,差异有统计学意义(P0.05)。结论采用高屈曲旋转平台假体实施人工膝关节置换术治疗膝OA,中期效果显著,有利于患者膝关节功能及活动度提升,且不增加并发症风险。     

旋转平台与后稳定固定平台膝关节假体分析

目的比较分析旋转平台、后稳定固定平台膝关节假体对初次单侧膝关节置换患者术后患肢功能恢复的影响。 方法回顾性分析初次行单侧膝关节置换术的350例膝关节病患者临床资料。纳入病例均经临床、X线片或CT确诊。其中选择旋转平台膝关节假体180例设为A组,选择后稳定固定平台膝关节假体170例设为B组,比较两组手术前后美国特种外科医院膝关节评分(HSS)、美国膝关节协会评分(KSS)、膝关节屈曲度(ROM)及静态稳定性指标,记录两组并发症情况。其中HSS、KSS、ROM、静态稳定性指标等计量资料行t检验,并发症等计数资料行χ²检验。 结果两组术后6个月HSS评分、KSS评分、ROM、横轴向躯体重心(GCP)偏移位置均较术前显著上升,GCP漂移轨迹均显著减少,差异有统计学意义(A组手术前后t ＝－105.415、－107.890、－23.829、56.647、78.339;B组手术前后t ＝－103.736、－136.420、－22.141、－26.077、69.119,均为P<0.05);A组术后6个月GCP漂移轨迹显著小于B组(t ＝7.082,P<0.05);两组并发症发生率比较差异无统计学意义(χ² ＝2.361,P>0.05)。 结论旋转平台与后稳定固定平台假体均能明显促初次单侧膝关节置换患者术后患肢功能恢复,并发症类似,但前者相对静态稳定性更好。     

全膝关节置换术后股骨假体前屈角对膝关节功能康复的影响

目的 观察全膝关节置换术后股骨假体前屈角对患者膝关节功能康复的影响。方法 回顾性分析自2021-08—2022-08采用全膝关节置换术治疗的70例膝骨性关节炎,根据术后患膝关节X线正侧位片股骨假体前屈角度进行分组,正常患者术后股骨假体前屈角度5°～7°,35例股骨假体前屈角正常（A组）,35例股骨假体前屈角偏大（B组）。两组术前活动情况无明显差异,术中均在规范操作下完成手术,选择相同厂家的膝关节假体系统,假体置入位置、松紧度均无异常,术后采用相同的康复训练方案。比较两组手术时间、术中出血量、膝关节功能HSS评分、疼痛VAS评分、股骨假体俯屈角、胫骨平台后倾角以及膝关节伸直与屈曲活动度。结果 70例均获得为期1个月的门诊随访,术后症状均有所改善。两组手术时间、术中出血量比较差异无统计学意义（P>0.05）。A组术后1个月膝关节功能HSS评分为（84.74±4.78）分,B组为（79.89±4.43）分;A组术后1个月膝关节功能HSS评分较B组高,差异有统计学意义（P<0.05）。术后1个月膝关节功能HSS评分等级：A组优16例,良19例;B组优3例,良32例。A组术后1个月疼...     

胫骨平台后倾角变化对单髁关节置换术后关节功能及假体生存率的影响

目的 探讨第3代Oxford假体单髁膝关节置换术（unicompartmental knee arthroplasty,UKA后胫骨平台后倾角（posterior tibial slope,PTS）变化对膝关节功能及假体生存率的影响。方法 回顾性分析我院自2017年1月至2021年8月收治的194例（206膝）行内侧单髁膝关节置换术的病人,根据术前及术后后倾角变化差值进行分组：A组60例（63膝）,后倾角增大>2°;B组101例（108膝）,后倾角变化≤2°;C组33例（35膝）,后倾角减小>2°。采用美国特种外科医院（HSS）评分、牛津大学膝关节评分（OKS）及患膝关节屈伸活动度（ROM）评估膝关节功能。统计206膝术后并发症情况并采用Kaplan-Meier法评估假体生存率。结果 三组术后均获得良好的膝关节功能。术前三组间HSS评分、OKS评分及ROM的差异无统计学意义（P>0.05）;末次随访时三组间HSS、OKS评分差异有统计学意义（P<0.05）,其中B组HSS评分高于A、C两组,OKS评分低于A、C两组,而三组间ROM差异无统计学意义（P>0....     

第三代Oxford单髁假体安放位置对人工单髁关节置换术近期疗效的影响北大核心CSCD

目的探讨第3代Oxford单髁假体安放位置对人工单髁关节置换术(unicompartmental knee arthroplasty,UKA)近期疗效的影响。方法将2015年9月—11月收治并符合标准的26例(26膝)膝关节前内侧骨关节炎患者纳入研究,其中15例采用单柱型假体(单柱组)、11例采用双柱型假体(双柱组)行UKA。两组患者性别、年龄、体质量指数、骨关节炎Kellgren-Lawrence分级和术前美国特种医院(HSS)评分等一般资料比较,差异均无统计学意义(P>0.05)。随访时功能评价采用HSS评分、美国西部Ontario与McMaster大学骨关节炎评分(WOMAC)、牛津膝关节评分(OKS)和美国膝关节学会评分(KSS);组件安放位置评价采用Oxford单髁假体影像学评分,同时记录衬垫脱位等并发症发生情况。结果单柱组随访时间为24～27个月,平均26.2个月;双柱组随访时间为24～26个月,平均25.2个月。术后仅双柱组2例出现衬垫脱位。末次随访时,两组膝关节功能HSS评分、WOMAC评分、OKS评分、KSS评分比较,差异均无统计学意义(P>0.05)。X线片测量示两组股骨组件、胫骨组件以及总体组件影像学评分比较,差异均无统计学意义(P>0.05)。相关分析示,两组假体位置和术后关节功能间无相关性(P>0.05)。结论在一定安全范围内,第3代Oxford单髁假体安放位置对UKA近期疗效无明显影响。     

高屈曲度假体与全髁型假体早期临床疗效比较

目的 对比高屈曲度假体与传统全髁型假体全膝关节表面置换术后早期临床效果的差异。方法 选取2004年10月至2005年10月间50例（67个膝关节）接受全膝关节表面置换术的膝骨关节炎患者，随机分为A组（高屈曲度假体组，使用LPS—Flex假体）和B组（全髁型假体组／TTC组，使用PFC∑及GⅡ假体）。A组包括26例患者（32个膝关节），男5例，女21例，平均年龄（65．29±5．96）岁。B组包括24例患者（35个膝关节）。男4例，女20例，平均年龄（64．32±8．32）岁。平均随访时间为1年8个月（1～2年）。结果 术前HSS评分为A组（58．61±11．40）分，B组（55．73±13．42）分，两组间无显著差异；术前膝关节活动度为A组（92±12．6）。（-15°～110°），B组（95±11．8）。（-15°～115°），两组间无显著差异。术后末次随访时HSS评分为A组（91．42±6．1）分，B组（92．67±6．33）分，两组间无显著差异；膝关节活动度为A组（124．68±10．32）。（-5°～137°），B组（102．56±15．44）。（-5°～118°），两组间有显著差异，A组患者膝关节屈曲功能明显优于B组。术后并发症包括：A组1例双膝全膝关节置换患者术后3个月时右膝关节感染，1例患者术后深静脉血栓形成；B组1例单膝全膝关节置换患者术后2周伤口脂肪液化，2例患者术后发生深静脉血栓。结论 全膝关节置换术中使用高屈曲度假体与使用传统全髁型假体相比，在改善患者疼痛、恢复行走功能以及手术并发症率方面无显著差别，但术后所能达到的屈曲度有显著差异。     

旋转平台与固定平台全膝关节置换术的对比研究及髌骨置换与否对疗效的影响

目的评估旋转平台和固定平台假体全膝关节置换(TKA)两型假体间的疗效有无差异及髌骨置换与否对疗效的影响。方法选取同一医师施行的78侧初次TKA进行回顾。术前诊断包括骨关节炎、类风湿性关节炎等。施行固定平台TKA手术的患者共30侧,14侧置换髌骨;施行旋转平台TKA手术的共48侧,36侧置换髌骨。术前和术后随访行膝HSS评分、测量关节伸直角度和屈曲角度,以比较两型假体TKA疗效;比较髌骨置换组与未置换组TKA疗效;在髌骨置换组与未置换组中,分别比较固定平台TKA和旋转平台TKA的疗效。结果成功随访76侧,平均25.2个月。旋转平台组术后HSS评分、伸直角度与固定平台组间的差异无统计学意义,前者术后的屈曲角度(112.0±11.5)°优于固定平台组间的差异有统计学意义(t=3.270,P0.01)。髌骨未置换组术后HSS评分、伸直角度与髌骨置换组(102.5±15.1)°组间差异有统计学意义(t=2.469,P0.05;t=3.747,P0.01),术后屈曲角度与后者间的差别无统计学意义。髌骨未置换组中,旋转平台TKA与固定平台TKA的术后HSS评分、屈曲角度无差异,伸直角度差别无临床意义。髌骨置换组中,旋转平台TKA术后HSS评分、伸直角度与固定平台TKA间的差异无统计学意义,前者术后的屈曲角度(112.9±13.0)°与后者术后的屈曲角度(96.7±18.4)°比较差异有统计学意义(t=2.838,P0.05)。结论旋转平台假体与固定平台假体TKA术后总体疗效相似,旋转平台假体能够更好地改善关节屈曲角度;置换髌骨并不能更好地改善膝关节功能。     

CR型活动衬垫膝关节假体的临床应用

[目的]观察使用CR型活动衬垫膝关节假体进行人工全膝关节置换的临床效果,评价其临床应用的意义。[方法]随访观察本院从1997年11月~2005年6月,使用CR型活动衬垫膝关节假体进行膝关节置换的效果,其中218个患者、301个膝关节获得了满意的随访,平均随访48.7个月。采用X线片及HSS评分进行临床疗效评定。[结果]HSS评分从术前平均53.3分增加到术后的91.3分。活动范围从术前平均伸-9.5°、屈64.3,°到术后平均伸0°、屈97.5°。术前最大内翻角25,°最大外翻角15°;术后总外翻角为0°~10°,平均5.3°。感染2例,假体周围骨折2例,胫骨内侧平台塌陷1例,后外侧不稳1例。其余未见有骨溶解现象。[结论]CR型活动衬垫膝关节假体不但在理论上有其独特的优越性,而且在临床上中短期效果令人满意。     

无菌翻修膝关节置换术23例临床分析

目的分析无菌性假肢松动者无菌翻修膝关节置换术的临床疗效。方法无菌性假肢松动接受无菌翻修膝关节置换术病人23例,观察病人术前及术后6天、1个月、6个月膝关节主动和被动关节活动度(ROM)、美国特种医院膝关节评分(HSS评分)、美国膝关节协会膝评分与功能评分(KSKS评分)。结果术后3天膝关节正侧位X片假体位置显示良好,术后两周伤口愈合情况良好。平均住院时间13.5天,住院期间未出现感染、褥疮、深静脉血栓等并发症,出院时膝关节活动度良好,病人均可双拐辅助下地行走,膝关节疼痛消失。病人随访时间平均12.5个月,病人满意率为95.65%。病人术后6天、1个月、6个月主动膝关节ROM及被动膝关节ROM均高于术前;病人术后6天、1个月、6个月HSS评分及KSKS评分均高于术前,差异有统计学意义(P0.05)。结论无菌翻修膝关节置换术对于假体无菌性松动造成的无菌翻修术的治疗效果较好。     

不同程度屈膝挛缩畸形人工全膝关节置换的早期疗效比较

目的探讨不同程度屈膝挛缩畸形行人工全膝关节置换术(totalkneearthroplasty,TKA)后的早期疗效。方法回顾性分析2000年1月～2003年12月行TKA的65例97膝屈膝挛缩畸形患者资料。其中骨关节炎51例74膝,类风湿关节炎14例23膝。单膝置换33例33膝,双膝同时置换32例64膝。按屈膝挛缩畸形程度不同将患者分成A、B两组,A组屈曲挛缩<20°(0～15°)32例49膝,B组屈曲挛缩≥20°(20～60°)33例48膝。A、B两组膝关节术前屈曲挛缩度数、活动度(rangeofmotion,ROM)、KSS(kneesocietyscore)评分及功能评分分别为10.7±8.0°、104.6±20.0°、29.1±18.0、32.6±20.7和28.2±7.8°、60.8±26.6°、12.1±13.2、26.8±18.1,各指标组间比较差异均有统计学意义(P<0.05)。术中均采用Scorpio后稳定型骨水泥固定假体,行初期置换。术后3～4d在同一康复师指导下行CPM及主动功能锻炼。结果患者获随访8个月～3年6个月,平均2年7个月。A、B组术后膝关节屈曲挛缩度数、ROM、KSS评分和功能评分分别为0.4±2.1°、108.6±19.0°、82.1±13.8、72.3±29.1和1.3±3.2°、98.6±16.4°、75.9±8.2、81.4±26.9,组间比较差异均无统计学意义(P>0.05)。术后患者总满意度为94.6%,无深部感染及再翻修者。结论膝关节屈膝挛缩畸形严重与否对TKA的早期疗效无明显影响;TKA后ROM有“趋中”现象;术后早期行膝关节功能锻炼也是获得功能改善的重要环节之一。     

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。     

Osteolysis in failed total knee arthroplasty: a comparison of mobile-bearing and fixed-bearing knees

BACKGROUND: Osteolysis is an important complication associated with total knee arthroplasty. The purpose of this study was to compare the prevalence of osteolysis after failed total knee arthroplasty with a mobile-bearing prosthesis and after failed arthroplasty with a fixed-bearing prosthesis. METHODS: Eighty revision total knee arthroplasties performed between 1995 and 1998 were included in this study. All had radiographic evidence of advanced polyethylene wear. The mobile-bearing group consisted of thirty-four knees with a Low Contact Stress implant, and the fixed-bearing group included forty-six knees. The average time (and standard deviation) from the primary operation to the revision was 102.8 +/- 26.5 months in the mobile-bearing group and 96.0 +/- 30.1 months in the fixed-bearing group. The prerevision radiographs and operative findings were reviewed. RESULTS: The prevalence of osteolysis was significantly higher in the mobile-bearing group (47%; sixteen of thirty-four knees) than in the fixed-bearing group (13%; six of forty-six knees) (p = 0.003). The distal part of the femur was involved in thirteen knees in the mobile-bearing group and in four knees in the fixed-bearing group. Seventeen knees had osteolysis in the posterior aspect of the femoral condyle, which was the most common site of osteolysis; however, twelve of them had no evidence of osteolysis on prerevision radiographs. CONCLUSIONS: The prevalence of osteolysis was higher in the knees with a mobile-bearing prosthesis than in those with a fixed-bearing prosthesis. The osteolysis was predominantly on the femoral side, adjacent to the posterior aspect of the condyle. Radiographic evaluation of osteolysis in the distal part of the femur may not be reliable and usually leads to an underestimation of the degree of osteolysis.     

In vivo kinematics for fixed and mobile-bearing posterior stabilized knee prostheses

This is the first in vivo kinematic study to compare mobile-bearing with fixed-bearing prostheses in patients who had total knee arthroplasties. Femorotibial contact positions for 40 patients implanted with either a fixed-bearing or mobile-bearing prosthesis were analyzed using videofluoroscopy. Femorotibial contact paths were determined using a computer automated model-fitting technique. Nineteen of 20 patients in each group experienced posterior femoral rollback of their lateral condyles, with a mean of 3.6 and 3.7 mm for fixed-bearing and mobile-bearing prostheses respectively. Eighteen patients who had mobile-bearing prostheses and 17 patients with fixed-bearing knee prostheses experienced a normal pattern of axial rotation of 7.3 degrees and 4.1 degrees respectively. Eleven of 20 (55%) patients who had mobile-bearing prostheses implanted and eight of 20 (40%) patients who had fixed-bearing prostheses implanted did not experience femoral condylar lift-off. The remaining knees had condylar lift-off less than 2.4 mm for fixed-bearing prostheses and 1.7 mm for mobile-bearing prostheses, respectively. Patients who had mobile-bearing prostheses implanted experienced greater axial rotation and less condylar lift-off than patients who had fixed-bearing prostheses implanted. Both cruciate ligaments are sacrificed for the mobile and fixed-bearing total knee replacements. The results from the current study showed that, in both groups, the majority of patients experienced kinematics similar to those of a normal knee. However, the extent of lateral femoral condyle posterior rollback and the extent of axial rotation were less.     

固定平台型与活动平台型膝关节假体人工全膝关节置换术后膝前痛的比较研究

目的比较采用固定平台型与活动平台型膝关节假体行人工全膝关节置换术(total knee arthroplasty,TKA)后发生膝前痛的差异。方法 2008年1月-10月收治72例骨性关节炎患者,其中37例采用固定平台型膝关节假体置换(固定平台组),35例采用活动平台型膝关节假体置换(活动平台组)。固定平台组:男8例,女29例;年龄57～76岁,平均69.6岁。左膝20例,右膝17例。体重55～92 kg,平均66.7 kg。体重指数(body mass index,BMI)为17.6～37.3,平均26.2。病程3～22年。根据膝关节学会评分系统(KSS)标准评定膝评分(29.4±15.3)分,功能评分(33.4±16.8)分。髌骨评分(7.2±2.5)分,疼痛评分(2.5±2.2)分。Insall-Salvat(iI-S)指数为1.6±0.3。活动平台组:男9例,女26例;年龄58～73岁,平均68.2岁。左膝30例,右膝5例。体重50～86 kg,平均67.9 kg。BMI为18.4～34.4,平均25.6。病程6～18年。KSS膝评分(30.9±14.7)分,功能评分(31.4±14.4)分。髌骨评分(6.8±3.1)分,疼痛评分(2.0±2.3)分。I-S指数为1.6±0.2。两组患者一般资料比较,差异均无统计学意义(P>0.05),具有可比性。结果两组患者术后切口均Ⅰ期愈合,无下肢深静脉血栓形成及肺栓塞发生。患者术后均获随访,随访时间为12～16个月。术后活动平台组发生膝关节感染1例,膝关节脱位1例,膝关节弹响3例;固定平台组发生膝关节弹响1例。两组末次随访时KSS膝评分及功能评分、疼痛评分及髌骨评分比较,差异均无统计学意义(P>0.05);两组以上指标分别与术前比较,差异均有统计学意义(P<0.05)。末次随访时两组适合角、外侧髌骨角、髌骨倾斜角、髌骨外移距离、髌骨移位距离及I-S指数比较,差异均无统计学意义(P>0.05)。术后1～5个月固定平台组7例(18.9%)、活动平台组5例(14.3%)出现膝前痛。两组膝前痛发生率比较,差异无统计学意义(χ2=0.227,P=0.634)。术后出现膝前痛患者KSS膝评分、功能评分、髌骨评分及I-S指数与未出现膝前痛患者比较,差异均有统计学意义(P<0.05);其余各指标差异均无统计学意义(P>0.05)。结论采用固定平台型与活动平台型膝关节假体行TKA术后膝前痛发生率及术后近期疗效无明显差异。     

Comparison of mobile-bearing and fixed-bearing total knee arthroplasty: a prospective randomized study

The purpose of this prospective randomized study was to compare the postoperative recovery and early results of 2 groups of patients undergoing total knee arthroplasty: 107 patients received an established fixed-bearing posterior-stabilized prosthesis (Legacy Posterior Stabilized [LPS]), and 103 patients the meniscal-bearing prosthesis (Meniscal Bearing Knee [MBK]). Surgical procedures were the same for both groups except for posterior cruciate ligament management, which was sacrificed in the LPS group and spared but completely released from the tibia in the MBK group. At an average follow-up of 36 months, knee, function, and patellar scores were comparable in both groups. The LPS group showed a significantly higher maximum flexion than the MBK group (112 degrees vs 108 degrees). Using a fixed-bearing or a mobile-bearing design did not seem to influence the short-term recovery and early results after knee arthroplasty. Key words: total knee arthroplasty, mobile bearing, knee prosthesis, meniscal-bearing knee, posterior stabilized, prospective randomized.     

A comparison of fixed-bearing and mobile-bearing total knee arthroplasty at a minimum follow-up of 4.5 years

BACKGROUND: Durable long-term independent results with the Low Contact Stress rotating-platform (mobile-bearing) and the Insall Burstein-II (fixed-bearing) total knee prostheses have been reported, but no studies describing either the mid-term or long-term results and comparing the two prostheses are available, to our knowledge. METHODS: Thirty-two patients who had bilateral arthritis of the knee with similar deformity and preoperative range of motion on both sides and who agreed to have one knee replaced with a mobile-bearing total knee design and the other with a fixed-bearing design were prospectively evaluated. Comparative analysis of both designs was done at a mean follow-up period of six years, minimizing patient, surgeon, and observer-related bias. Clinical and radiographic outcome, survival, and complication rates were compared. RESULTS: Patients with osteoarthritis had better function scores and range of motion compared with patients with rheumatoid arthritis. However, with the numbers available, no benefit of mobile-bearing over fixed-bearing designs could be demonstrated with respect to Knee Society scores, range of flexion, subject preference, or patellofemoral complication rates. Radiographs showed no difference in prosthetic alignment. Two knees with a mobile-bearing prosthesis required a reoperation: one had an early revision because of bearing dislocation and another required conversion to an arthrodesis to treat a deep infection. CONCLUSIONS: We found no advantage of the mobile-bearing arthroplasty over the fixed-bearing arthroplasty with regard to the clinical results at mid-term follow-up. The risk of bearing subluxation and dislocation in knees with the mobile-bearing prosthesis is a cause for concern and may necessitate early revision. LEVEL OF EVIDENCE: Therapeutic Level II.     

Comparison of a mobile with a fixed-bearing unicompartmental knee implant

Two well-matched groups of patients with unicompartmental knee arthroplasties were compared. The first 51 knees were treated with a fixed-bearing knee implant and the second 50 knees were treated with a mobile meniscal-bearing implant. Followup was 7.7 years for the patients with fixed-bearing implants and 6.8 years for patients with mobile-bearing implants. Both groups functioned well clinically. Radiographic analysis with 3-foot standing views taken preoperatively showed both groups had an average varus alignment of -2 degrees. Postoperatively patients with fixed-bearing implants had an average +2.6 degrees alignment and the patients with mobile-bearing implants had +5.5 degrees alignment, which was significantly different. Survivorship analysis based on component loosening and revision showed a 99% survival for the meniscal-bearing implant and 93% survival for the fixed-bearing implant at 11 years. However, the fixed-bearing knee implants failed significantly more often because of tibial component failure, in six of eight knees, at an average of 6.3 years. The mobile-bearing implants showed a trend to fail because of arthritic degeneration in the lateral compartment, at an average of 10 years, although not statistically significant. The mobile-bearing implants had no tibial component failures. These differences may be attributable to implant design or surgical technique.     

A mobile-bearing total knee prosthesis compared with a fixed-bearing prosthesis. A multicentre single-blind randomised controlled trial

Before proceeding to longer-term studies, we have studied the early clinical results of a new mobile-bearing total knee prosthesis in comparison with an established fixed-bearing device. Patients requiring bilateral knee replacement consented to have their operations under one anaesthetic using one of each prosthesis. They also agreed to accept the random choice of knee (right or left) and to remain ignorant as to which side had which implant. Outcomes were measured using the American Knee Society Score (AKSS), the Oxford Knee Score (OKS), and determination of the range of movement and pain scores before and at one year after operation. Preoperatively, there was no systematic difference between the right and left knees. One patient died in the perioperative period and one mobile-bearing prosthesis required early revision for dislocation of the meniscal component. At one year the mean AKSS, OKS and pain scores for the new device were slightly better (p < 0.025) than those for the fixed-bearing device. There was no difference in the range of movement. We believe that this is the first controlled, blinded trial to compare early function of a new knee prosthesis with that of a standard implant. It demonstrates a small but significant clinical advantage for the mobile-bearing design.     

活动平台与固定平台全膝关节置换的比较研究

目的评价人工全膝关节置换术中使用活动平台和固定平台假体治疗膝骨关节炎的早期疗效。方法对2009年3月至2011年3月收治的诊断为膝骨关节炎的患者,随机应用活动平台型假体和固定平台型假体行全膝关节置换（total knee arthroplasty,TKA）手术。记录术前及随访时术膝的膝关节评分、疼痛评分、功能评分、髌骨评分和膝关节活动度,以及股骨角、胫骨角、膝外翻角、胫骨平台后倾角、截骨高度。结果术前活动平台组和固定平台组的年龄、体重指数、患膝内翻畸形、最大屈曲角度及屈曲挛缩度均无统计学差异（P〉0.05）。术后平均随访26个月,活动平台组和固定平台组的术前术后膝关节评分、疼痛评分、功能评分、髌骨评分均无统计学差异（P〉0.05）,都明显地改善了患膝的症状和功能。活动平台组和固定平台组的术后最大屈曲度间存在显著性差异（P〈0.05）。两组的股骨角、胫骨角、膝外翻角、胫骨平台后倾角、截骨高度和术前术后髌骨高度无显著性差异（P〉0.05）。结论活动平台型假体和固定平台型假体TKA均明显改善了患膝的症状和功能,两组的膝关节评分、功能评分、疼痛评分、髌骨评分及X线检查评价差异均无统计学意义。固定平台组的术后最大屈曲度大于活动平台组的最大屈曲度。