Influence of Patellar Morphology Classified by Wiberg Classification on Knee Joint Function and Patellofemoral Tracking After Total Knee Arthroplasty Without Patellar Resurfacing

BackgroundTo evaluate the influence of patellar morphology on knee joint function and patellofemoral tracking in patients with primary osteoarthritis after total knee arthroplasty (TKA) without patellar resurfacing.MethodsWe performed a retrospective study of 156 patients with primary osteoarthritis who underwent TKA without patellar resurfacing from April 2018 to July 2019. As per Wiberg classification, patients were divided into Wiberg type I (group A, n = 38), II (group B, n = 88), and III (group C, n = 30) groups. The clinical data, postoperative follow-up data, and radiological data between three groups were compared.ResultsThere was no statistically significant difference in the HSS score and Feller score between the three groups before surgery and at each follow-up point after surgery (P > .05). At the last follow-up, there were no significant differences in the height and relative thickness of the patella between the three groups (P > .05). However, the incidence of anterior knee pain was significantly higher in group C than in the group B (P < .05). The patellar tilt angle was significantly larger in group C than in the groups A and B (both P < .05). The patellar facet angle was significantly larger in group A than in group B and C, which was also significantly larger in group B than in group C (both P < .05).ConclusionPatients with three different morphologic types of the patella both exhibited improved knee joint function after TKA, however, patients with Wiberg type Ⅲ patella were more prone to have poor patellofemoral tracking and anterior knee pain after surgery.     

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.     

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.     

How Does Preoperative Central Sensitization Affect Quality of Life Following Total Knee Arthroplasty?

BackgroundCentral sensitization (CS) has been recently identified as a significant risk factor for persistent pain and patient dissatisfaction following total knee arthroplasty (TKA). However, it remains unclear as to whether the preoperative CS persists after the elimination of a nociceptive pain source by TKA, or how CS affects the quality of life after TKA.MethodsA total of 222 consecutive patients undergoing primary TKA were enrolled in the study. All patients were preoperatively screened for CS using the Central Sensitization Inventory (CSI) and categorized into either a CS (n = 55; CSI ≥ 40) or non-CS group (n = 167; CSI < 40). CSI, pain visual analog scale (VAS), Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index score, and satisfaction were recorded at postoperative 2 years.ResultsTwo years after TKA, preoperative CS remained unchanged; there was no difference between preoperative and postoperative CSI scores, and both preoperative and postoperative CSI severity levels were similar (P > .1). The CS group showed worse pain VAS, KSS, and Western Ontario and McMaster Universities Osteoarthritis Index scores than did the non-CS group (P < .01) and more patients in the CS group were dissatisfied with all activities (P < .01). However, a similar percentage of the CS group achieved the previously documented minimal clinically important difference in pain VAS and KSS, compared with the non-CS group. Multivariate regression analysis revealed that preoperative CSI scores were associated with dissatisfaction at postoperative 2 years.ConclusionPreoperative CS was persistent at 2 years after TKA. Although CS patients achieved comparable clinical improvement following TKA, CS patients had worse quality of life, functional disability, and dissatisfaction than non-CS patients.     

Do Changes in Patellofemoral Joint Offset Lead to Adverse Outcomes in Total Knee Arthroplasty With Patellar Resurfacing? A Radiographic Review

Background

Patellofemoral joint biomechanics contribute to anterior knee pain, instability, and dysfunction following total knee arthroplasty (TKA). Information about specific factors leading to anterior knee pain and dysfunction is currently limited. Changes in patellofemoral joint offset (PFO) refers to a mismatch between the preoperative and postoperative anteroposterior geometry of the patellofemoral joint. It remains unclear whether these changes lead to adverse outcomes in TKA.

Influence of Total Knee Arthroplasty on Patellar Kinematics and Patellofemoral Pressure

Background

Patellofemoral complications are one of the main problems after total knee arthroplasty (TKA). The design of the TKA component may affect the patellar biomechanics, which may be associated with this postoperative complication. The purpose of this study was to assess the influence of TKA and prosthesis designs on the patellar kinematics and patellofemoral pressure.

Routine Patellar Resurfacing During Total Knee Arthroplasty Is Not Cost-Effective in Patients Without Patellar Arthritis

BackgroundCurrently, the decision to resurface the patella is often made irrespective of the presence of patellar arthritis. The purpose of this study is to utilize the existing literature to assess cost-utility of routinely vs selectively resurfacing the patella.MethodsProspective randomized studies of patella resurfacing vs non-resurfacing in total knee arthroplasty (TKA) were identified through literature review. Data from these studies represented probabilities of varied outcomes following TKA dependent upon patella resurfacing. Using previously validated utility scores from the McKnee modified Health Utilities Index, endpoint utility values were provided for each potential outcome.ResultsLiterature review yielded a total of 14 studies with 3,562 patients receiving 3,823 TKAs, of which 1,873 (49.0%) patellae were resurfaced. Persistent postoperative anterior knee pain occurred in 20.9% vs 13.2% (P < .001) and patella reoperation was performed in 3.7% vs 1.6% (P < .001) of unresurfaced and resurfaced patella, respectively. In studies excluding those with arthritic patellae, the incidence of anterior knee pain was equivalent between groups and reoperation decreased to 1.2% vs 0% (P = .06). Patella resurfacing provided marginally improved quality-adjusted life-years (QALY) for both selective and indiscriminate patella resurfacing. When including all studies, the incremental cost per QALY was $3,032. However, when analyzing only those studies with nonarthritic patellae, the incremental cost per QALY to resurface the patella increased to $183,584.ConclusionPatellar resurfacing remains a controversial issue in TKA. Utilizing data from new prospective randomized studies, this analysis finds that routinely resurfacing arthritis-free patellae in TKA are not cost-effective.     

Patellar Denervation in Total Knee Arthroplasty Without Patellar Resurfacing and Postoperative Anterior Knee Pain: A Meta-Analysis of Randomized Controlled Trials

The aim of this meta-analysis was to investigate whether patellar denervation with electrocautery (PD) after total knee arthroplasty (TKA) could reduce the postoperative anterior knee pain (AKP). Five randomized controlled trials (RCTs) with 572 patients and 657 knees were eligible for this meta-analysis. Our results showed that PD was associated with less AKP, lower visual analogue scale (VAS), higher patellar scores and better knee function compared with no patellar denervation (NPD). Complications did not differ significantly between the two groups. The existing evidence indicates that PD may be a better approach, as it improves both anterior knee pain and knee function after TKA. Future multi-center randomized controlled studies with large sample sizes are required to verify the current findings.     

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.     

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.

Clinical Outcomes of a Modern Total Knee Arthroplasty Prosthesis Compared to Its Predecessor at 5-Year Follow-Up: Matched Pair Analysis

BackgroundResidual pain is an important cause of patient dissatisfaction after total knee arthroplasty (TKA). A recent study at our institution found that a modern prosthesis was associated with less residual and anterior knee pain at 2-year follow-up when compared to its predecessor. The aim of this study is to evaluate these implants at 5-year follow-up.MethodsFrom July 2012 to December 2013, 100 consecutive modern TKAs were identified from our prospective Institutional Review Board approved database. All patients with 5-year clinical follow-up (n = 77) were matched in a one-to-one fashion based on age, gender, body mass index, and follow-up with a predecessor TKA. Clinical outcomes were assessed with a patient-administered questionnaire for specifically anterior knee pain, painless noise, painful crepitation, and satisfaction. Overall function was assessed using Knee Society Scores and Western Ontario and McMaster University Osteoarthritis Index.ResultsAt 5-year follow-up, there were no significant differences between the modern TKA and a predecessor TKA in the Knee Society pain or function scores (P = .24 and P = .54, respectively). The overall prevalence of residual pain was less with the modern TKA compared to its predecessor (19.5% vs 36.3%; P = .02), but the prevalence of isolated anterior knee pain was similar in both cohorts (11.7% vs 22.1%; P = .09). There was no difference in painless noise (19.5% vs 13.3%; P = .28) or satisfaction scores (7.9 ± 2.4 vs 7.6 ± 2.6; P = .25) between the modern and predecessor cohorts.ConclusionAt 5-year follow-up, we found that both the modern and predecessor prostheses provided excellent clinical outcomes. The modern TKA was associated with less residual pain compared to its predecessor, but we were unable to detect differences in the prevalence of isolated anterior knee pain, painless noise, Knee Society Scores, or radiographic evaluation.     

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

BackgroundPatellar crepitus (PC) is a common complication after total knee arthroplasty (TKA) using a posterior-stabilized (PS) prosthesis. While numerous factors have been associated with PC development after PS-TKA, patellar resurfacing (PR) which directly impacts the patellofemoral joint kinematics has been underinvestigated. A prospective, randomized, controlled trial was conducted to (1) compare the PC incidence in PR and non-PR PS-TKA, (2) determine the time of PC presentation in PS-TKA, (3) identify radiographic parameters associated with PC, and (4) compare clinical outcomes of patients with and without PR.MethodsA total of 84 patients who underwent unilateral TKA using the Legion PS Total Knee System were randomized into PR group or non-PR group. PC incidence, time of PC presentation, radiographic parameters associated with PC development, and clinical outcomes were evaluated at 3 months, 6 months, 9 months, and 1 year postoperatively.ResultsPC occurred significantly more in the non-PR group (23.1% vs 7.3%, P = .048). Time of PC presentation in both groups was not different. Anterior knee pain was found in 16.7% of crepitus patients, and none required any surgical procedure. The non-PR knees had significant decreases in patellar shift index, patellar displacement, Insall-Salvati ratio, and patellar component height and increase in change in posterior femoral offset. Oxford and patellar scores were significantly better in the PR group at 9 months and 1 year.ConclusionGiven higher PC incidence and several worse clinical outcomes in the non-PR, we recommend resurfacing during PS-TKA with this knee system to avoid PC development.     

Different Factors Conduct Anterior Knee Pain Following Primary Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

Background

A systematic review and meta-analysis was performed to investigate the risks associated with anterior knee pain (AKP) following primary total knee arthroplasty (TKA).

The efficacy of patellar decompression for improving anterior knee pain following total knee arthroplasty without patellar resurfacing

Background

Anterior knee pain remains common following total knee arthroplasty (TKA). In this study, we evaluated the efficacy of patellar decompression via drilling for the treatment of anterior knee pain following TKA without patellar resurfacing.

Methods

A prospective cohort study was performed in 271 consecutive patients who underwent primary total knee replacement with patellar decompression (study group, n = 131) or without decompression (control group, n = 140). The patients were assessed according to the Knee Society rating, clinical anterior knee pain score, and British Orthopaedic Association patient-satisfaction score in each group. Each assessment was performed without the examiner knowing whether the patella had been decompressed. Radiographic evaluations were also performed according to the Knee Society scoring system for functional activity and our own severity grade system for patellofemoral articular change.

Results

There were no adverse events following patellar decompression. The overall prevalence of anterior knee pain was not significantly different between groups (p = 0.71). However, patients presenting pain over grade II after the operation in the study group were statistically low (p = 0.01). The overall postoperative knee scores were higher in the study group, but there were no significant differences between groups (p = 0.0731). Analyses of the radiographs revealed similar postoperative outcomes in both groups of knees.

Conclusions

As we observed significantly lower rates of anterior knee pain and no patellar complications following patellar decompression via drilling in TKA without patellar resurfacing, we recommend performing patellar decompression in cases of total knee replacement without patellar resurfacing.     

Foot Pain is Common,But Frequently Improves 1 Year After Total Knee Arthroplasty

BackgroundOsteoarthritis frequently affects multiple joints through the lower limbs. This study sought to examine the incidence of foot pain in subjects undergoing total knee arthroplasty (TKA) and determine if foot symptoms improved following surgery.MethodsSix hundred ten subjects undergoing TKA completed patient-reported outcome measures preoperatively, and at 6 and/or 12 months after surgery including the incidence and severity of foot or ankle pain, Knee Injury and Osteoarthritis Outcome Scores (KOOS) Joint Replacement, Oxford Knee Scores (OKS), EQ5D, and satisfaction.ResultsFoot or ankle pain was reported in 45% before, 32% at 6 months, and 36% at 12 months after TKA. Of those with preoperative foot pain, 42% at 6 months and 50% at 12 months reported no foot pain after TKA, and the Visual Analog Scale severity reduced from a mean of 4.0 before to 1.7 after surgery. Those with preoperative foot pain had lower baseline KOOS (P = .001), OKS (P = .001), and more depression/anxiety (P = .010), but experienced equivalent postoperative KOOS, OKS, and satisfaction with surgery, compared to those without foot pain.ConclusionFoot or ankle pain was reported by nearly half of TKA subjects, but resolved after surgery in 50%. Those with preoperative foot pain experienced at least equivalent improvement in knee-related symptoms and mobility compared to those without foot pain. The presence of foot pain should not be a deterrent to TKA.     

Total Knee Arthroplasty in Patients With Knee Osteoarthritis: Effects on Proprioception. A Systematic Review and Best Evidence Synthesis

BackgroundImpact of total knee arthroplasty (TKA) on proprioception remains to be determined. The aim of this systematic review is to analyze factors influencing proprioception in patients with knee osteoarthritis (OA) undergoing TKA.MethodsA systematic literature search was conducted on 3 medical electronic databases: PubMed, PeDRO, and Cochrane Collaboration. The Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were used. Risk of bias analysis and best evidence synthesis were performed. Three main aspects were investigated: the presence of preoperative, surgical, and postoperative factors influencing proprioception in OA patients undergoing TKA.ResultsSearch identified 1601 records. After screening, 19 papers were used for the analysis of 676 patients. Proprioception generally improved but often remained impaired after surgery. Strong evidence was found for no influence of prosthesis design on proprioception. Moderate evidence was found for patellar resurfacing not affecting proprioception, varus deformity negatively influencing proprioception, and time elapsed from surgery positively influencing proprioception. Limited evidence was found for valgus deformity, OA grade, intact anterior cruciate ligament, and anteroposterior joint laxity negatively affecting knee proprioception, and for muscle strength and sensorimotor training not affecting proprioception. Finally, conflicting evidence was found for better postoperative proprioception vs preoperative level.ConclusionProprioception in OA patients undergoing TKA improves but remains impaired after surgery. The best evidence synthesis demonstrated no influence of prosthetic design, while the role of the treatment remains unclear. This warrants for further research efforts to study proprioceptive impairment to better manage OA patients undergoing TKA.     

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。     

初次全膝关节置换术后膝前痛预防的研究进展

全膝关节置换术（total knee arthroplasty,TKA）是治疗终极膝关节病变的有效方法,能有效缓解疼痛,纠正畸形,改善功能,进而提高患者的生活质量.目前,患者的满意程度越来越被认为是评价TKA的一个重要因素.而膝前痛作为初次TKA后的常见并发症,是指发生于膝前或者髌骨周围的疼痛,这严重影响了患者膝关节功能的改善和其对手术的满意程度.因此,膝前痛的减轻成为TKA的重要目标.目前,认为膝前痛的主要机制是髌股关节的高接触应力造成的软骨下骨内压升高和并发于髌骨运行轨迹异常导致的髌骨周围软组织病变.近年来针对如何预防全膝关节置换术后膝前痛的发生进行了大量研究,但是由于各种各样的原因,至今为止不管是髌骨置换,保留髌骨行髌骨周围去神经化,还是活动平台体都不能取得确切而良好的效果.由此可见,初次TKA后膝前痛的防治仍然是一个棘手的问题.此问题的解决,需要对膝前痛发生原因、膝关节假体及髌股关节生物力学特性做进一步研究,并经过大规模的随机对照试验的论证.     

Knee Flexion Angle Following Total Knee Arthroplasty Relates to a Preoperative Range of Motion of the Hip

BackgroundMany factors have been reported to affect postoperative range of knee flexion after total knee arthroplasty (TKA); however, no study has reported the impact of preoperative range of motion of the hip to the postoperative flexion angle of the knee thus far.MethodsOf 38 consecutive patients who underwent posterior-stabilized TKA, we assessed 21 patients after excluding 17 patients who met exclusion criteria. The range of motion of the knee and the hip, age, body-mass index, serum albumin level, HbA1c, Kellgren–Lawrence grade, knee extension strength and radiological femorotibial angle as well as postoperative knee flexion angle at three months were evaluated. The preoperative data and the knee flexion angle at three months after TKA were compared using Spearman''s rank correlation coefficient.ResultsKnee flexion angle at three months after TKA was positively correlated with preoperative flexion (ρ = 0.616, p = 0.007) and external rotation angle (ρ = 0.576, p = 0.012) of the hip as well as preoperative knee flexion angle (ρ = 0.797, p = 0.001). There were no correlations between postoperative knee flexion angle and other preoperative data.ConclusionsPatients with restricted flexion and/or external rotation of the hip may have contractures of Gluteus maximus, Gluteus medius and Tensor fasciae latae, which can cause hypertension of iliotibial tract. It may cause decreased internal rotation of the tibia when the knee is flexed, which affects postoperative knee flexion angle, thus limited flexion and/or external rotation of the hip might restrict knee flexion angle following TKA.     

髌骨置换与否对全膝关节置换术后疗效的影响

目的 探讨膝骨关节炎患者行全膝关节表面置换时髌骨置换与否对术后疗效及并发症发生的影响.方法 对2007年1月至2011年12月之间行人工全膝关节置换术的170例(237膝)骨关节炎患者,按髌骨置换(126膝)和未置换(111膝)分为2组.对术前和末次随访时两组的HSS评分、膝前痛评分、膝关节活动度、最大屈曲度数、屈曲畸形及手术时情况和患者满意度等进行对比分析.结果使用SPSS 17.0统计软件包进行统计学分析.结果 在170例(237膝)OA患者中161例(21 3膝)获得随访,平均随访时间(40.94±8.02)个月,置换组HSS评分由术前的(40.19±8.14)分增加到末次随访时的(87.45±6.00)分(P＜0.05),膝前痛评分由(4.13±1.08)分升高到(19.47±4.04)分(P＜0.05);未置换组HSS评分由(40.00±6.74)分上升到(88.93±4.92)分(P＜0.05),膝前痛评分由(3.58±2.26)分变化到(13.61±3.89)分(P＜0.05);患者满意度置换组为80.91％,未置换组为61.17％(P＜0.05).在HSS评分、膝关节活动度、最大屈曲度数、屈曲畸形等方面两组差异无统计学意义.而在膝前痛评分、患者满意度、手术时间、术中失血量等方面差异有统计学意义.结论 当膝关节骨关节炎患者进行全膝关节置换术时,若术前存在膝关节疼痛严重、患者期望较高、不适合长时间手术,应行髌骨置换.