Secondary patellar resurfacing in total knee arthroplasty: results of multivariate analysis in two case-matched groups

Although patellofemoral symptoms after patellar-retaining knee arthroplasty are common, no evidence has been published in the literature on the potential benefit from patellar resurfacing at a later stage. This study evaluates the effect of secondary (delayed) patellar resurfacing using comparisons between 2 case-matched groups of patients with primary and secondary patellar resurfacing. Furthermore, multivariate statistical methods were applied to study factors that may influence the final outcome. Our results suggest that although significant clinical improvement was seen after delayed patella resurfacing, the outcome of secondary patellar resurfacing is inferior to that expected for a similar group of patients with primary resurfacing. Furthermore, the timing (delay period) of the secondary resurfacing procedure appears to negatively affect the final outcome. This suggests that secondary patellar resurfacing, when indicated, should be considered at an early stage.     

膝关节置换术中髌骨置换与非髌骨置换比较的Meta分析

[目的]系统评价全膝关节置换术中髌骨置换与否对术后疗效的影响,为临床治疗提供参考。[方法]全面搜索国内外关于膝关节置换术中髌骨置换和非髌骨置换的随机对照研究资料,按照既定的纳入、排除标准,核定检出符合评价标准的文献,提取所需研究数据,采用RevMan 4.2软件进行Meta分析。[结果]纳入随机对照研究16篇,共计1 922例膝关节置换术。Meta分析结果显示,髌骨置换组术后5年内发生膝前痛的风险降低,加权后RR=0.53,95%CI(0.30,0.94),但5年后二者无明显统计学差异。髌骨置换组术后5年以上发生再手术的风险低,加权后RR=0.35,95%CI(0.18,0.66),但5年内二者无明显统计学差异。膝关节KSS评分不论是亚组分析还是总体分析,均无统计学差异。总体分析结果,KSS评分加权均数差值为0.44,95%CI(-1.22,2.09)。[结论]全膝关节置换术中髌骨置换与非髌骨置换相比,术后5年内膝前痛发生率低,术后5年以上再手术的风险低,关节评分无明显差别。髌骨置换与非髌骨置换的优劣仍需大规模多中心的RCT来进一步研究。     

Patellar resurfacing complications in total knee arthroplasty

Purpose

The ideal management of the patella during total knee arthroplasty (TKA) is still controversial. Patellar retention is generally associated with an increased rate of anterior knee pain; however, patient satisfaction is similar in cases of replacement or retention. When the patella is replaced, potential severe complications can occur. Aim of this study was to retrospectively review results of a continuous series of patients having been treated with TKA and patella resurfacing.

Methods

The charts of 1,600 consecutive total knee prostheses were analysed to evaluate the rate of patellar resurfacing. All implants were posterior stabilized; 310 patients having received a patellar replacement were reviewed at follow-up (FU) examination. Complete physical examination as well as administration of the Hospital for Special Surgery (HSS) score was performed. X-rays analysis included weightbearing anteroposterior (AP) and lateral views of the injured knee and bilateral skyline views at 30° flexion.

Results

Two hundred and eighty patients were available for clinical and imaging investigation at an average FU of 96 (58–144) months. Mean age at the time of surgery was 70 (62–80) years. Mean HSS score was 85.9 ± 7.6. The overall rate of patellofemoral complications was 7 % (19 cases); 13 patients claimed anterior knee pain, five had symptomatic patellar maltracking and one had patellar component loosening.

Conclusion

Our data are in accordance with those available in the literature. Recent meta-analyses demonstrated lower risk of re-operation after patellar resurfacing. However, when complications of the resurfaced patella occur, they can be potentially catastrophic events.     

Patellar clunk syndrome after posterior stabilized total knee arthroplasty

Two hundred thirty-six posterior stabilized total knee arthroplasties (TKAs) were performed consecutively. Twenty-seven patellar clunk syndromes were identified in 25 patients. Insall-Salvati ratio, position of joint line, postoperative patellar height, and anterior-posterior position of tibial tray were measured. It was found that postoperative low-lying patella (P<.001) and anterior placement of tibial tray (P=.011) was associated with patellar clunk syndrome. Thirteen patients had bilateral TKAs of the same prosthesis (5 bilateral AMK knees and 8 bilateral Insall Burstein knees) but unilateral patellar clunk syndrome. The nonclunk sides were used as control for comparison with the clunk sides. The congruency and tilting of the patellar button in the skyline view were documented. It was observed that the congruency of the patellar button was less satisfactory in the clunk side (P=.019).     

Patellar Denervation Reduces Postoperative Anterior Knee Pain After Patellar Resurfacing Total Knee Arthroplasty: A Randomized Controlled Trial

BackgroundThe benefit of patellar denervation (PD) in patellar resurfacing total knee arthroplasty (TKA) is still debatable. This prospective, randomized controlled trial investigated whether circumferential PD should be performed in patellar resurfacing TKA.MethodsA total of 241 patients who underwent unilateral TKA were randomized into PD or non-PD groups. Incidence, intensity, and presentation time of anterior knee pain (AKP) and clinical outcomes were evaluated at 3, 6, 9, 12, 18, and 24 months postoperatively.ResultsThe incidence of AKP was significantly lower in the PD group (6.4% vs 16.2%, P = .032). The intensity of AKP and patient satisfaction scores were significantly better in the PD group at 3 months but not after 3 months. The presentation time of AKP mostly occurs at 3 months after surgery. The Knee Society score, range of motion, Oxford score, patellar score, activity of daily living score, and visual analog scale of overall knee pain were not significantly different between the two groups during the follow-up period.ConclusionGiven that PD can improve AKP and patient satisfaction at an early period postoperatively without jeopardizing clinical outcomes at no additional cost, this inexpensive procedure readily available in nearly every operation room is strongly recommended during primary TKA with patellar resurfacing.     

全膝关节置换术中髌骨置换与否对膝前痛发生的影响

[目的]回顾性分析、比较全膝关节置换术中髌骨置换与否对膝前痛发生的影响,为临床治疗提供参考。[方法]对1994年10月~2004年10月行人工全膝关节置换术病人125例(148膝)按髌骨置换(84膝)和未置换(64膝)分为2组,并对其随访资料进行分析,膝关节评分采用HSS评分系统,髌骨评分采用Feller评分标准。结果使用SPSS统计软件进行统计学分析。[结果]置换组HSS评分由术前的(39.6±39.8)分进步为末次随访时的(90.9±8.2)分,髌骨评分由(14.4±6.4)分进步到(25.2±4.8)分,膝前痛分数也由(4.6±3.9)分进步为(10.6±4.1)分;未置换组HSS评分由术前的(38.8±9.8)分进步为(90.2±8.9)分,髌骨评分由(14.2±6.2)分进步到(25.1±4.8)分,膝前痛分数也由(4.8±3.8)分进步为(10.3±4.1)分。2组患者末次随访时膝前痛均较术前明显减轻,差异有显著性意义;置换组与未置换组比较,膝前痛减轻的差别无显著性意义。[结论]无论髌骨置换与否,患者的合理选择和正确的手术操作是避免术后膝前痛的关键所在。     

Failure of the all-polyethylene patellar component after total knee arthroplasty

From 1991 to 1996, 953 cases of porous-coated anatomic modular knee prostheses with all-polyethylene patellar components were implanted. Among them, 4 cases had breakage of the patellar component at the peg-button interfaces. One had loosening of the patellar component by cutting out the patellar bony bed. Heavy body weight, weakness of the pegs of the all-polyethylene patellar component, and osteonecrosis of the patella were conceived as the causes of failure.     

Patellofemoral function after total knee arthroplasty: gender-related differences

The purpose of the study was to evaluate patellofemoral results in 2 comparable groups of 50 patients, men and women, undergoing total knee arthroplasty. The average follow-up was 6 years. The implant was posteriorly stabilized with a dome patellar arthroplasty. The patients were studied using Knee Society knee and functional scores and the Hospital for Special Surgery (HSS) patellar score. Radiologic study included standard and weight-bearing axial views and a computed tomographic scan to assess component rotation. The 2 groups achieved satisfactory and similar knee scores; women had a significantly lower functional and patellar scores. The incidence of lateral patellar tilt, subluxation, and lateral impingement was decreased in weight-bearing axial views compared with non-weight bearing. Medial bony impingement was evident only in weight-bearing views and correlated with pain (P < .05).     

Patellar clunk in total knee arthroplasty using modified Sigma posterior stabilized femoral component

Aim

The purpose of this study was to evaluate the efficacy of the enhanced PS femoral component design released in 2008 by DePuy. The patellar clunk syndrome has been reported in a significant number of patients following total knee arthroplasty. Design modifications of the implant have been made to reduce the incidence of the patellar clunk, especially in the posterior substituted designs.

Methods

130 total knee replacements performed using the enhanced PS femoral components were followed-up with clinical and radiographic evaluations.

Results

Patellar clunk was seen in 3 of the 130 knees (2%). This is much less than the incidence of patellar clunk reported until now.

Conclusions

Removal of the sharp ridge in the intercondylar groove in the newer implant seems to have been effective in reducing the incidence of the patellar clunk. It also indicates that the sharp ridge was the most probable cause of the clunk.     

髌骨钻孔减压改善全膝关节置换术后膝前疼痛

目的探讨通过髌骨钻孔减压术改善全膝关节置换术(TKA)后膝前痛的临床疗效。方法将符合标准的113例行TKA的骨关节炎患者按数字法随机分为两组:54例为减压组,TKA术中联合髌骨钻孔减压术;59例为非减压组,仅施行TKA不联合髌骨钻孔减压术。术后观察两组患者切口愈合情况、相关并发症、KSS评分及膝前痛发生率。结果两组患者切口均一期愈合,无严重并发症发生,113例均获满12个月的完整随访。KSS评分:减压组术后明显高于非减压组;术后膝前痛的发生率明显低于非减压组,差异均有统计学意义(P0.05)。结论 TKA术中联合髌骨减压术可以在一定程度上改善膝关节KSS评分及降低术后膝前疼痛的发生率。     

The Outcome of Total Knee Arthroplasty With and Without Patellar Resurfacing up to 17 Years: A Report From the Australian Orthopaedic Association National Joint Replacement Registry

BackgroundPatellar resurfacing in total knee arthroplasty (TKA) remains a controversial issue after more than 4 decades of TKA. Despite a growing body of evidence from registry data, resurfacing is still based largely on a surgeon’s preference and training. The purpose of this study is to provide long-term outcomes for patellar resurfaced compared to when the patella is not resurfaced.MethodsData from the Australian Orthopaedic Association National Joint Replacement Registry (1999-2017) were used for this study. The analysis included 570,735 primary TKAs undertaken for osteoarthritis. Hazard ratios (HRs) and 17-year cumulative percent revision rates were used to compare revision rates between 4 subgroups: minimally stabilized (MS) patellar resurfacing, posterior stabilized (PS) patellar resurfacing, MS unresurfaced, and PS unresurfaced patella. Additional analyses of the patellar implant type and a comparison of inlay and onlay patellar resurfacing were also performed.ResultsFor all primary TKA, procedures where the patella was not resurfaced have a higher rate of revision compared to procedures where the patella was resurfaced (HR, 1.31; confidence interval, 1.28-1.35; P < .001). Unresurfaced PS knees have the highest cumulative percent revision at 17 years (11.1%), followed by MS unresurfaced (8.8%), PS resurfaced (7.9%), and MS resurfaced (7.1%). Inlay patellar resurfacing has a higher rate of revision compared to onlay patellar resurfacing (HR, 1.27; confidence interval, 1.17-1.37; P < .001).ConclusionResurfacing the patella reduces the rate of revision for both MS and PS knees. MS knees with patellar resurfacing have the lowest rate of revision. Onlay patella designs are associated with a lower revision rate compared to inlay patella designs.     

The natural history of anterior knee pain in 2 posterior-stabilized, modular total knee arthroplasty designs

Anterior knee pain (AKP) has been a persistent complaint after total knee arthroplasty; however, the natural course of this complaint has not been fully investigated. This is a 10-year follow-up report of a prospective, randomized study between the Insall-Burstein II (Zimmer, Warsaw, IN) and the Press Fit Condylar Modular (Johnson & Johnson, Raynham, MA) knees. Up to one third of total knee arthroplasties will experience mild to moderate AKP at 1-year follow-up, which will persist in approximately 30% of these previously symptomatic knees at 10-year follow-up. New-onset AKP will develop in approximately 10% of previously asymptomatic knees.     

Onlay Patellar Resurfacing in a Posterior-Stabilized Total Knee Arthroplasty Increases Patellar Crepitus Complication: A Randomized,Controlled Trial

BackgroundPatellar crepitus (PC) is a potentially problematic complication after total knee arthroplasty (TKA) more commonly occurring with a posterior-stabilized (PS) prosthesis. Patellar resurfacing has been reported to reduce PC complications; however, no study has compared the PC complication rates between 2 different resurfacing techniques, namely inlay and onlay.MethodsA prospective, randomized controlled trial was conducted to compare the PC complication between inlay and onlay patellar resurfacing techniques. A total of 222 patients who underwent unilateral TKA using a Legion PS Total Knee System were randomized into 2 groups. PC incidence, time of PC presentation, radiographic parameters associated with PC development, and clinical outcomes were evaluated at 3, 6, 9, 12, 18, and 24 months postoperatively.ResultsPC occurred significantly more in the onlay group (17.9% vs 6.5%, P = .009). Time of PC presentation in both groups was not different. Anterior knee pain was found in 11.5% of PC patients, and none required any surgical procedure. Postoperative radiographic parameters, range of motion, Knee Society score, Oxford score, patellar score, incidence and intensity of anterior knee pain, and visual analog scale of overall knee pain were not significantly different between the 2 groups during the follow-up period.ConclusionTo reduce the chance of PC development, we suggest an inlay patellar resurfacing technique during PS-TKA with this knee system.     

The need for patellar resurfacing in total knee arthroplasty: a literature review

The controversy over whether or not to routinely resurface the patella during a total knee arthroplasty has persisted despite three decades of successful joint replacement procedures. Advocates for routine patellar resurfacing admit the occasional need for secondary patellar resurfacing and declare increased incidence of anterior knee pain in patients with non‐resurfaced patellae as a cause for worry. Surgeons that leave the patella unresurfaced cite avoidance of complications that include patellar fracture, avascular necrosis, patellar tendon injury and instability. This review discusses the available literature on patellar resurfacing through an evidence‐based analysis of randomized and pseudo‐randomized controlled trials and published meta‐analyses to date. The published literature seems to favour resurfacing the patellar routinely. Selective patellar resurfacing would be the ideal solution if sound pre‐operative criteria could be established. So far, a method for accurately predicting which patients can avoid patellar resurfacing has not been found. Future research looking at patellar resurfacing should concentrate on developing criteria for selecting those patients that would benefit from patellar resurfacing and those that would do as well without resurfacing, and thus, limiting potential surgical complications.     

Osteoarthritis knee with patellar fracture in the elderly: single-stage fixation and total knee arthroplasty

Periarticular fractures that occur in a previously osteoarthritic knee, especially in an elderly patient, will be associated with other comorbidities and is a treatment challenge. Early mobilization is a key treatment principle in the geriatric population. We present a case report of an elderly diabetic patient with osteoarthritis of the knee joint who sustained a patellar fracture and was treated with single-stage primary total knee arthroplasty and fixation of the patellar fracture.     

Patellar reconstruction using distal femoral autograft in a patellectomized patient undergoing total knee arthroplasty

Patellectomized patients have less satisfactory clinical outcomes after total knee arthroplasty because of a decreased extensor mechanism efficiency and potential instability attributable to loss of anterior restraint. We report a patient, with a prior history of patellectomy, who underwent simultaneous patellar reconstruction using distal femoral autograft during the total knee arthroplasty. The patient has been followed up for 24 months with excellent postoperative knee scores with radiographically established graft viability.     

Patellar Resurfacing in Total Knee Arthroplasty: A Cost-Effectiveness Analysis

Background

This study estimates the cost-effectiveness of patellar resurfacing in total knee arthroplasty (TKA).

Adding Patella Resurfacing After Circumpatellar Electrocautery Did Not Improve the Clinical Outcome in Bilateral Total Knee Arthroplasty in Chinese Population: A Prospective Randomized Study

Background

In total knee arthroplasty (TKA), handling of the patella surface is still quite controversial. We carried out a prospective randomized study to compare circumpatellar electrocautery plus patella resurfacing vs circumpatellar electrocautery only in the single-staged bilateral TKA in Chinese population.

髌骨置换与否对全膝关节置换效果的影响

目的评价髌骨置换与否对全膝关节表面置换的影响。方法对2000年1月至2001年6月间行膝关节表面置换的165例病人随机分为髌骨置换组和不置换组。置换组均采用同一种膝关节假体系统，由同组医生完成，术前和随访时评价HSS评分、髌骨评分和髌骨适合角、髌骨高度等影像学结果。所有评价均采用双盲的方式。结果在HSS评分和髌骨评分方面，两组无统计学差异。影像学评价两组无统计学差异。髌骨置换组的手术时间明显长于非置换组。结论对于骨关节炎病人，不置换和置换髌骨临床效果相当，影像学表现无明显区别。但置换组的手术时间更长。不论置换与否，手术时应注意对下肢力线的矫正。     

髌骨合理设计在全膝关节置换中的临床效果

目的探讨髌骨合理设计后重塑在全膝关节置换(TKA)中的临床效果。方法根据股骨假体滑动轨迹及所需置换髌骨的形态,对56例TKA患者(72膝)术中进行髌骨合理设计并重塑,观察患者术后的关节活动度及疼痛情况,用KSS膝关节评分系统评定治疗效果。结果 56例均获得随访,时间6~18个月。仅1例患者膝关节活动度70°,活动较差,但疼痛明显减轻;其余患者屈曲活动度在0°~110°。KSS评分:优69膝,良2膝,中1膝,优良率达到98.6%。结论术中根据股骨假体滑动轨迹对髌骨合理设计并重塑,可以使未进行髌骨置换的TKA患者取得满意的治疗效果。