后稳定型与后交叉韧带保留型膝关节假体在人工膝关节置换术后的早期临床疗效比较分析

目的比较后稳定型膝关节假体(Posterior Stabilized Total Knee Prostheses PS)与后交叉韧带保留型膝关节假体(Posterior Cruciate-Retaining Total Knee Prostheses CR)在人工膝关节置换术(Total Knee Arthoplasty TKA)后的临床疗效,并分析两种假体在TKA术后可能存在的相关问题。方法回顾自2010年1月至2012年12月我院收治的晚期骨关节炎、并进行人工全膝关节置换术治疗的66位患者资料,其中PS假体30例,CR假体36例,观察两组患者手术时间、术后引流量,以及术后2周、1年、3年的下肢力线、膝关节活动度(Range Of Motion ROM)、膝关节最大屈曲角度、术后视觉模拟评分法((Visual Analogue Score VAS)、纽约特种外科医院膝关节功能评分(hospital for special surgery knee score HSS)评分、髋膝关节炎评分(The Western Ontario and Mc Master Universities,WOMAC,Osteoarthritis Index)。结果 PS组的术中手术时间、术后引流量明显大于CR组,差异具有统计学意义(P0.05),术后两周PS组膝关节ROM、膝关节最大屈曲角度明显大于CR组,差异具有统计学意义(P0.05),而在术后1年、3年的随访数据中均无明显差异。结论对于无严重畸形的初次膝关节置换,后稳定型膝关节假体与后交叉韧带保留型膝关节假体均具有重要的临床使用价值,可有效改善患者的膝关节功能,降低膝关节疼痛评分等。     

特定序列CT扫描检测全膝关节置换假体旋转稳定性

目的:探讨人工全膝关节假体旋转稳定性与髌骨轨迹的关系,阐明CT技术检测假体轴向旋转稳定性的优越性。方法:28例施行人工全膝关节置换术后出现单纯髌股关节并发症的患者进行膝关节轴位CT扫描,选择股骨髁上轴和胫骨结节作为CT扫描的参考标志来测量股骨假体和胫骨假体的旋转角度,分析旋转稳定性与髌股关节并发症的相关性。结果:研究组患者的全关节假体(股骨假体 胫骨假体)旋转角度存在过度内旋,内旋的角度与髌股关节并发症的严重程度存在对应关系。轻度(1°～4°)内旋对应髌骨轨迹不良髌骨翘起,中度(3°～9°)内旋对应髌骨半脱位,重度(6°～18°)内旋对应早期的髌骨脱位和晚期的髌骨假体失败。结论:假体的内旋可能是人工膝关节置换手术后出现髌股关节并发症的重要原因,使用CT技术可以确定人工关节假体是否存在旋转不良,提示进行单一假体翻修或全关节翻修手术。     

全膝关节置换术后关节线上移对临床功能和运动学参数的影响

目的探讨关节线上移对后稳定假体和后交叉韧带保留假体的全膝关节置换(TKA)患者的临床功能和运动学参数的影响。方法收集北京积水潭院2013年1月至2015年12月使用GⅡ行全膝关节置换术的病例,符合标准的纳入研究,共57膝。按手术假体分为后稳定假体(PS)组和交叉韧带保留假体(CR)组。随访1年,临床功能使用美国膝关节协会(AKS)评分、AKS功能评分和Feller髌骨评分进行评定。用透视技术采集患者的运动学数据,并用2D-3D的注册匹配技术将假体的数字模型还原在影像学动态数据上进行测量。分析患者屈伸活动时股骨内髁、股骨外髁在胫骨平台上的运动,以及股骨胫骨之间的相对旋转。结果 PS组术后的AKS评分(P0. 05)、AKS功能评分(P0. 05)、Feller髌骨评分(P0. 01)和术后活动度(P0. 01)均比CR组好。PS组股骨内髁的移动是(4. 9±3. 0) mm,外髁的移动是(12. 8±3. 3) mm,股胫关节旋转12. 9°±4. 5°; CR组股骨内髁的移动是(4. 3±3. 5) mm,外髁的移动是(7. 9±4. 2) mm,股胫关节旋转6. 7°±5. 9°。PS组更接近生理。结论关节线(JL)上移对CR假体的不良影响比PS假体大,在关节线上移的病例中尽量选择PS假体。     

全膝关节翻修中应用金属垫块和髓腔柄组成的翻修假体系统重建骨缺损和关节稳定性:12例随访

背景:全膝关节翻修比初次全膝关节置换技术上更具挑战性,骨缺损或侧副韧带的缺失,使假体的固定、力线的保持及稳定性的重建更加复杂和困难。目的:观察全膝关节翻修过程中采用金属垫块和髓腔柄组成的翻修假体系统的临床效果。方法:2004-02/2008-01对12例12膝行全膝关节翻修,其中假体松动翻修8例,感染后假体置入4例。翻修过程中使用金属垫块修复AORI-Ⅱ型非包容性骨缺损及恢复关节线水平,并使用髓内假体柄来增加翻修假体的稳定性,使用的假体为组合式髁限制型膝关节OPTETRAK.CCK。翻修后进行随访观察,采用膝关节协会评分及膝关节活动度评估膝关节功能。结果与结论:翻修后随访6～37个月,平均21个月。患者膝关节协会评分从翻修前27分增加到最后随访时的75分,膝关节活动度由翻修前63°增加到最后随访时的97°。除一例患者皮肤伤口感染延迟愈合外,未见下肢静脉血栓、肺部感染等并发症出现。提示采用金属垫块和髓腔柄组成的翻修假体系统重建全膝关节翻修术中非包容性骨缺损和软组织平衡,既可以方便手术操作,获得即刻稳定性,又可以提高翻修成功率。     

术中应用不同假体对全膝关节置换术后引流的影响

目的 探讨术中使用后方稳定型（posterior cruciate stabilization, PS）与后交叉韧带保留型（posterior cruciate retention, CR）假体对全膝关节置换术（total knee arthroplasty, TKA）术后引流的影响。方法 回顾性分析2018年6月至2018年10月终末期骨性关节炎行全膝关节置换的患者102例，其中62例采用后交叉韧带保留型（CR）假体（CR组），40例采用后稳定型（PS）假体（PS组）。所有患者术中均使用止血带、关节腔注射氨甲环酸（tranexamic acid, TXA），术后患肢屈曲1 h、引流管夹毕1 h、患肢冰敷24 h。收集术后2、4、24、48 h引流量和引流液中血红蛋白（hemoglobin, HB）含量，以及术后2、24、48 h静脉血中的血红蛋白（HB）含量。统计术后输血情况、早期感染并发症例数。结果 102例患者随访3个月，术后总引流量CR组（292.9±128.3）mL比PS组引流量为（355.2±136.8）mL少，两组比较差异有统计学意义（P＜0.05）。术后1 d的CR组的引流量比PS组少，两组比较差异有统计学意义（P＜0.05）。术后24 h的CR组引流液中血红蛋白含量比PS组明显下降，两组比较差异有统计学意义（P＜0.05）。术后24、48 h的PS组静脉血中血红蛋白含量比CR组明显下降，两组比较差异有统计学意义（P＜0.05）。CR组2例输了2 U红细胞，PS组2例输了1 U红细胞、9例输了2 U红细胞。102例患者术后早期均未出现感染并发症。结论 与PS假体相比，采用CR假体可减少患者的失血量、术后引流量少、降低全膝关节置换术后贫血的发生、减少围术期输血率。     

股骨侧远端生物固定假体在高龄患者全髋关节翻修中的应用

背景：对高龄患者行人工全髋关节翻修时如何正确选择股骨侧假体固定方式,可否应用组配式股骨假体处理此类难题? 目的：验证股骨侧生物固定型假体在老年人全髋翻修后的效果。 方法：采用远端固定生物型股骨假体对11例75岁以上股骨侧假体松动患者进行翻修。11例股骨骨缺损根据Paprosky分型,Ⅰ型2髋,Ⅱ型2髋,ⅢA型7髋。 结果与结论：11例患者均随访16个月以上,患者Harris评分从翻修前的37分(22~49分)改善至随访结束时的89分(78~92分),优良率>90%,无患者发生再次松动。翻修后X射线片显示假体周围骨质密度和厚度明显增加。提示远端固定生物型假体可在股骨远端髓腔内获得可靠的轴向及抗旋转初始稳定性,尤其适用于伴有近端骨缺损的高龄患者的翻修治疗。     

骨水泥与非骨水泥型全膝关节假体置换效果的系统评价

背景：国外研究调查显示,在全膝关节置换中有95.2%采用骨水泥进行假体固定,但是也有专家学者认为使用骨水泥固定假体风险高。 目的：应用Cochrane系统评价的方法评价膝关节置换中骨水泥型与非骨水泥型假体置换的效果差异。 方法：检索Medline(1996年1月至2011年8月)、Embase(1980年1月至2011年8月)、Cochranelibrary (2011年8月)、中国生物医学文献数据库(CBM, 1990年1月至2011年8月)及相关参考文献,收集骨水泥型和非骨水泥型假体全膝关节置换的随机对照试验,采用Cochrane的方法学评价文献质量,应用RevMan5.1.2 进行Meta分析。比较骨水泥型和非骨水泥型假体在术后生存率、稳定性、相关并发症、翻修率、异位骨化的差异。并使用GRADEpro version3.2.2软件对纳入研究进行证据评级。 结果与结论：纳入8个随机对照试验,共1 381例患者,实验组(骨水泥组)676例,对照组(非骨水泥组)705例。4个研究比较了骨水泥组和非骨水泥组假体置换后≤5年组的膝关节生存率,两组差异有显著性意义,说明置换后≤5年骨水泥组生存率高。4个研究比较了置换后>5年组膝关节生存率,两组差异有显著性意义,说明置换后>5年组骨水泥假体组生存率高。3个研究在不同随访时间比较了置换后假体稳定性,结果显示两组间在假体稳定性上差异无显著性。4个研究在不同随访时间比较了置换后假体相关的并发症,两组间在假体相关并发症上比较差异无显著性意义。5个研究在不同随访时间比较了置换后翻修率,两组间在假体翻修率上差异无显著性意义。3个研究在不同随访时间比较了置换后假体异位骨化,两组间在置换后假体异位骨化上差异无显著性意义。两组置换后疗效均较术前明显提高,组间比较的Meta 分析结果显示,不论是≤5年组还是>5年组,均是骨水泥型假体生存率均高于非骨水泥型假体生存率,两组在稳定性、相关并发症、翻修率、异位骨化等方面差异均无显著性意义(P > 0.05)。     

CR假体与PS假体全膝关节置换治疗膝骨性关节炎合并膝外翻畸形的疗效分析

目的 比较后交叉韧带保留型（CR）假体与后方稳定型（PS）假体行人工全膝关节置换术（TKA）治疗膝骨性关节炎合并膝外翻畸形的临床疗效。方法 回顾性分析南昌大学附属赣州医院关节外科2019年5月至2021年5月收治的60例（60膝）膝骨性关节炎合并膝外翻畸形患者资料,均为单侧置换。30例采用CR假体行TKA治疗（CR组）,30例采用PS假体行TKA治疗（PS组）。比较两组患者的手术时间、术中失血量、术后引流量、术后3 d血红蛋白（Hb）下降量及深静脉血栓发生情况;比较两组患者手术前后膝外翻角;比较两组患者术后1周、1个月、3个月、6个月、1年疼痛视觉模拟评分（VAS）、膝关节活动度（ROM）、美国特种外科医院膝关节评分（HSS）。结果 60例患者均顺利完成TKA手术,所有患者随访13 ～ 28个月,平均（18.51±0.90）个月。CR组术中出血量、术后引流量、术后3 d的Hb下降量较PS组减少（P＜0.05）;两组手术时间相当、术后均无深静脉血栓发生,差异无统计学意义（P＞0.05）;两组手术前后膝外翻角的比较差异无统计学意义（P＞0.05）;CR组术后1周、1个月VAS评分较PS组更低（P＜0.05）,两组术后3个月、6月、1年VAS评分比较差异无统计学意义（P＞0.05）;CR组术后1周、1个月、3个月膝关节ROM和HSS评分优于PS组（P＜0.05）,两组术后6个月、1年膝关节ROM和HSS评分比较差异无统计学意义（P＞0.05）。结论 采用CR或PS假体行TKA手术治疗膝骨性关节炎合并膝外翻畸形均可有效纠正膝关节畸形、减轻膝关节疼痛、改善膝关节活动度及功能,取得满意临床疗效;但相对PS假体,CR假体保留了后交叉韧带,减少了股骨髁部截骨量,从而减少手术出血,更好减轻早期术后疼痛,有助于TKA术后早期功能康复。     

打压植骨技术在人工关节假体翻修术中修复骨缺损的应用

骨缺损的修复是人工关节置换术,尤其是翻修术中的难题.打压植骨(impaction bone grafting,IBG)技术是目前人工关节翻修术修复严重骨缺损的主要手段之一,该方法是将颗粒状的自体或异体骨充填于骨缺损后,用与假体配套的打击器,逐层植骨逐层压缩,形成压缩的骨壁,直到假体试模获得轴向和旋转稳定,目的是提供假体的初始稳定性及重建骨结构.……     

Zweymüller SLR-Plus~非骨水泥柄用于髋关节翻修的中期效果

背景:SL-Plus非骨水泥柄在初次人工髋关节置换中已取得了很好的疗效,但SLR-Plus柄在翻修术特别是感染病例翻修过程中的应用效果仍有待观察。目的:观察以Zweymüller SLR-Plus非骨水泥柄行髋关节翻修的临床效果。方法:对1997年11月至2013年5月以SLR-Plus股骨柄行人工髋关节翻修的39例(41髋)患者进行了随访,其中男26髋,女15髋;年龄34-73岁,平均53岁;翻修骨水泥柄36髋,非骨水泥柄5髋。随访X射线片上的假体变化情况;根据Brooker分类进行异位骨化分级,记录异位骨化发生部位及发生率;对髋关节行Harris功能评定并分析假体生存率。结果与结论:31例33髋获得随访,随访1-16年。患者的平均Harris评分由术前的34分(13-64分)增加到末次随访时的85分(55-94分)。32髋(97%)假体获得良好稳定性;1髋出现1 mm透亮线但无任何症状;1髋出现骨溶解并股骨假体远端穿出股骨皮质而需再翻修;9髋发生异位骨化,其中Brooker 1级2髋,2级4髋,3级3髋;未见术后感染复发。以影像学证明假体松动作为失败标准,利用Kaplan-Meier生存分析方法计算假体随访期间存活率为92%。提示SLR-Plus股骨柄具有良好的即刻稳定性及远期稳定性,用于髋关节翻修术中能达到令人较满意的中期效果。     

Intraoperative assessment of midflexion laxity in total knee prosthesis

BackgroundSoft-tissue balancing of the knee is fundamental to the success of a total knee arthroplasty (TKA). In posterior-stabilized TKA, there is no stabilizer of the anterior–posterior translation in the midflexion range in which the cam-post mechanism does not engage yet. Therefore, instability in the midflexion range is suspected to occur in posterior-stabilized TKA. The purpose of this study was to measure the joint gap throughout a full range of motion and to analyze the joint gap laxity in the midflexion range after implantation of a mobile-bearing posterior-stabilized total knee prosthesis.MethodsJoint gap kinematics in 259 knees with varus osteoarthritis were measured during TKAs using a tensor device with the same shape of a total knee prosthesis of the same design was used. After the implantation of a mobile-bearing posterior-stabilized prosthesis and the reduction of the patellofemoral joint, the joint gap was measured at 0°, 30°, 60°, 90°, 120°, and 145° of flexion.ResultsThe center size of the joint gap was tight in extension and deep flexion and loose at midflexion ranges, especially at 30° of flexion (p < 0.001). The symmetry of the joint gap was varus at 0° and 145° of flexion (p < 0.001).ConclusionsOur results showed the joint gap laxity in the midflexion range after the implantation of a mobile-bearing posterior-stabilized prosthesis. Our new tensor device, which can attach the polyethylene insert trial, will provide the important information about the joint gap kinematics after implantation of total knee prostheses.Level of evidenceIV.     

Evaluation of anteroposterior accelerometric change after bi-cruciate stabilized total knee arthroplasty and posterior stabilized total knee arthroplasty

BackgroundIn conventional total knee arthroplasty (TKA), the anterior cruciate ligament (ACL) is resected. ACL dysfunction causes knee instability and is regarded as one factor in poor TKA outcomes. In bi-cruciate stabilized (BCS) TKA, the implant reproduces ACL function and provides anterior stability. The objective of this study was to evaluate preoperative and postoperative X-rays and accelerometer gait measurements in patients who underwent BCS TKA and posterior-stabilized (PS) TKA to assess the postoperative acceleration changes of knees after these procedures and to compare them in terms of joint range of motion (ROM) and the New Knee Society Score (New KSS).MethodsThe subjects were 60 patients, 30 of whom underwent BCS TKA and 30 PS TKA. Joint ROM, New KSS, lateral X-rays of the standing extended knee, and accelerometer data were evaluated 12 months postoperatively.ResultsThere was no significant difference in joint ROM between the groups. Both had good New KSS results, but the functional activity score was significantly higher after BCS TKA than after PS TKA. X-rays showed a lower posterior offset ratio after BCS TKA than after PS TKA, with anteroposterior positioning closer to that of the normal knee.Accelerometer data showed that postoperative anteroposterior acceleration on the femoral side in the stance phase and swing phase was lower after BCS TKA than after PS TKA.ConclusionCompared with PS TKA, BCS TKA resulted in a higher functional activity score, closer positioning to that of the normal knee on lateral X-ray, and lower anteroposterior acceleration on the femoral side.     

Collateral ligament length change patterns after joint line elevation may not explain midflexion instability following TKA

Midflexion instability (MFI) after TKA is a phenomenon often described as varus–valgus instability between 30° and 45° knee flexion. The exact mechanisms causing MFI remain unclear, but elevation of the joint line (JLE) may be one possible cause. In an in silico approach using 4 subject specific musculoskeletal models, the length change patterns of the collateral ligaments during knee flexion (relative to the extended knee) were calculated for the anatomically reconstructed joints as well as for JLEs of 5 and 10 mm. Analysis of the distance between the ligaments’ attachment sites (DA) in midflexion revealed a relative decrease in DA magnitude after JLE for both collateral ligaments in comparison to the anatomically reconstructed knee. This finding suggests that JLE could contribute to MFI. However, the anterior ligament regions also experienced a DA increase (MCL) or only a slight DA decrease (LCL) for each JLE simulated. From this perspective, the anterior ligament portions are unlikely to slacken in midflexion and JLE is unlikely to contribute greatly to MFI. In conclusion, our findings did not support the idea that JLE is a major contributor to midflexion instability for this particular ultra-congruent implant design.     

Gait analysis comparison of cruciate retaining and substituting TKA following PCL sacrifice

The role of the posterior cruciate ligament (PCL) remains controversial in total knee arthroplasty (TKA), with some surgeons who believe in PCL sacrifice and substitution and others who believe in PCL preservation for stability. Manufacturers have developed both cruciate-substituting/posterior stabilized (PS) implants typically used when the ligament is sacrificed and cruciate retaining (CR) implants designed for ligament preservation. However, studies demonstrate excellent clinical results with CR implants despite PCL sacrifice. This study sought to determine functional stability differences between PS and CR TKAs following PCL sacrifice. Eighteen (9 matched pairs) subjects with either a PS or CR TKA and sacrificed PCL and a normal contralateral knee were subjected to physical exam and gait analysis (walking, stair ascent and descent) using a staircase model, passive reflective arrays and an optoelectric system. No differences were detected between the two groups among any of the measured parameters (knee flexion angle, knee flexion moment, knee power absorption, pelvic tilt). PCL sacrifice in a well-balanced cruciate retaining TKA did not result in instability during stair descent based on gait parameters. The decision to use a posterior stabilized design when faced with an incompetent PCL intraoperatively should be based on factors other than anticipated instability.     

Intraoperative changes in medial joint gap after posterior femoral condylar resection,posterior osteophyte removal,and femoral component placement during primary total knee arthroplasty

Background“Mid-flexion stability” is important for superior patient satisfaction following total knee arthroplasty (TKA). Thus, it is important to control medial joint gap intraoperatively as a countermeasure. However, reports on the precise intraoperative changes in medial joint gap during TKA are scarce. This study evaluated the intraoperative changes in medial joint gap during TKA.MethodsWe studied 167 knees with varus osteoarthritis that underwent 80 cruciate-retaining (CR) and 87 posterior-stabilized (PS) TKAs between January 2018 and December 2020. We measured the intraoperative changes in medial joint gap with a tensor device at 137.5 N.ResultsThe medial joint gap after posterior femoral condylar resection was significantly increased not only at 90° of flexion but also at 0° of extension in CR and PS TKAs (p < 0.01). The medial joint gap after posterior osteophyte removal was significantly increased not only at 0° of extension but also at 90° of flexion in CR and PS TKAs (p < 0.01). The medial joint gap at 0° of extension was reduced by 0.60 mm after femoral component placement in PS TKA.ConclusionSurgeons need to pay close attention to these intraoperative changes in medial joint gap by measuring the medial joint gap before and after each procedure or assuming the changes in those values before bone cutting to achieve superior patient satisfaction following TKA.     

Patella related problems as common reason for revision of NexGen PS® total knee arthroplasty without patella resurfacing: An analysis of 5911 primary total knee arthroplasties registered in the Dutch Arthroplasty Register

BackgroundPatella resurfacing remains controversial in primary total knee arthroplasty (TKA). The aim of this study was to investigate if there was a difference in revision rate and reason for revision within 8 years after single brand primary cemented TKA with or without patella resurfacing, using data from the Dutch Arthroplasty Register.MethodsAll primary TKA surgeries with a posterior stabilized cemented primary NexGen®, between 2010 and 2013 with diagnosis osteoarthritis were analyzed (n = 5911). Multivariate cox regression analyses were performed to analyze differences in revision rate between TKA with or without patella component, and was adjusted for age and previous surgery.ResultsOf 5911 TKA surgeries, 4795 were performed without patella resurfacing (81.1%) and 1116 with patella resurfacing (18.9%). There was a significant difference in patellar problems as reason for revision between patients after primary TKA with patella resurfacing (9.3%) and without patella resurfacing (29.9%) (p = 0.01). This was mostly caused by patellar pain (28.0%). There was no significant difference in cumulative revision rate within between TKA with patella resurfacing and without patella resurfacing.ConclusionIn conclusion, 30% of patients who need revision surgery after TKA using NexGen® PS without patella resurfacing the reason for revision is patella related problems, compared to 9% after TKA NexGen® PS with patella resurfacing. There was no difference in cumulative incidence of revision after primary surgery of all TKA’s using NexGen® PS with or without patella. To reduce the probability of reoperation for patella related problems, our data suggest the patella should be resurface during primary TKA.     

A tensor with a flat surface overestimates midflexion laxity in total knee arthroplasty: Comparison between a tensor with a flat-shaped surface and a tensor with an insert-shaped surface

BackgroundSoft tissue balance is important for the success of total knee arthroplasty (TKA). Various types of tensors have been developed for the precise measurement of a gap. We hypothesized that the surface shape of the tensor that contacted the TKA component affected the gap measurement. This study aimed to compare the gaps obtained with flat and insert-shaped surface tensors.MethodsTwo senior surgeons performed 95 TKAs (Vanguard-PS:55 knees; Persona-PS:40 knees). The joint gap was measured in each static knee flexion status (0°, 30°, 45°, 60°, 90°, 120°, and full flexion). We compared the gaps measured with a flat surface tensor and an insert-shape surface tensor. We defined a significant change as a gap difference of >1 mm with a statistical significance.ResultsIn Vanguard-PS, significant changes were observed at 30° and 45°. In Persona-PS, significant changes were observed at 30°, 45°, and 60°. In both implants, gaps measured with the flat tensor were larger than those measured with the insert tensor at approximately midflexion, and the significant changes disappeared in higher flexion position over midflexion.ConclusionsThe surface shape of the tensor affected the measurement of midflexion laxity in TKA. When measuring the gap with a flat tensor, the midflexion laxity was overestimated. A tensor with an insert-shaped surface should be used to measure the gap in TKA.     

Translational and rotational knee joint stability in anterior and posterior cruciate-retaining knee arthroplasty

This study investigated passive translational and rotational stability properties of the intact knee joint, after bicruciate-retaining bi-compartmental knee arthroplasty (BKA) and after posterior cruciate retaining total knee arthroplasty (TKA). Fourteen human cadaveric knee specimens were used in this study, and a robotic manipulator with six-axis force/torque sensor was used to test the joint laxity in anterior–posterior translation, valgus–varus, and internal–external rotation. The results show the knee joint stability after bicruciate-retaining BKA is similar to that of the native knee. On the other hand, the PCL-retaining TKA results in inferior joint stability in valgus, varus, external rotation, anterior and, surprisingly, posterior directions. Our findings suggest that, provided functional ligamentous structures, bicruciate-retaining BKA is a biomechanically attractive treatment for joint degenerative disease.     

No difference in the anteroposterior stability between the GRADIUS and multi-radius designs in total knee arthroplasty

BackgroundThis retrospective study aimed to compare stability and clinical and radiological outcomes of total knee arthroplasty (TKA) for the GRADIUS and multi-radius femoral designs after minimum of two-year follow-up.MethodsA total of 142 patients who underwent TKA using ATTUNE posterior stabilized (PS) implants (68 patients, GRADIUS group) or Persona PS implants (74 patients, multi-radius group) for degenerative osteoarthritis were included. After an average of 2-year follow-up, the anteroposterior (AP) stability at 30°, 60°, and 90° was measured using KT 2000 device and compared between the two groups. The clinical outcome measurements included range of motion (ROM) of the knee, patient-reported outcomes and anterior knee pain (AKP). For the clinical evaluation of mid-flexion instability, pain was evaluated using the visual analog scale (VAS) score recorded during climbing up or going down stairs. The radiolucent lines on knee radiographs obtained at final follow-up were evaluated and compared between two groups.ResultsThe average AP stability at 30° knee flexion was 5.7 mm in the GRADIUS group and 5.9 mm in the multi-radius group; however, the difference was not significant. The AP stability at 60° and 90° knee flexion was also similar in both groups. There were no significant differences in the ROM, patient-reported outcomes at follow-up, incidence of AKP and VAS scores between the two groups. There were no differences in the incidence of radiolucency around the components between the two groups.ConclusionThe GRADIUS design did not show any advantage with respect to the stability or clinical outcomes compared with the multi-radius design in TKA.