Does Implant Design Influence Failure Rate of Lateral Unicompartmental Knee Arthroplasty? A Meta-Analysis

Purpose Due to low incidence of isolated lateral osteoarthritis (OA), there are limited data on whether a fixed-bearing (FB) or a mobile-bearing (MB) design is superior for lateral unicompartmental knee replacement (UKR). The aim of this matched-pairs analysis was to compare both designs in terms of implant survival and clinical outcome. Methods Patients who received MB-UKR (Group A) and FB-UKR (Group B) at a single centre were matched according to gender, age at time of surgery and body mass index (BMI). Survivorship analysis was performed with the endpoint set as “revision for any reason”. Clinical outcome was assessed using the Oxford knee score (OKS), visual analogue scale for pain (VAS), patients’ satisfaction, University of California Los Angeles activity scale (UCLA) and the Tegner activity score (TAS). Results A total of 60 matched pairs were included with a mean follow-up (FU) of 3.4 ± 1.3 (range 1.2–5.0) years in Group A and 2.7 ± 1.2 (range 1.0–5.0) years in Group B. Survivorship between both groups differed significantly (Group A: 78.7%; Group B: 98.3%, p = 0.003) with bearing dislocation being the most common reason for revision in Group A (46.2%). The relative and absolute risk reduction were 92.2% and 20%, respectively, with 5 being the number needed to treat. There were no differences in OKS (Group A: 41.6 ± 6.5; Group B: 40.4 ± 7.7), VAS (Group A: 2.9 ± 3.2; Group B: 1.6 ± 2.2), UCLA (Group A: 5.7 ± 1.3; Group B: 5.9 ± 1.8) and TAS (Group A: 3.0 ± 1.0; Group B: 3.1 ± 1.2) between both groups on follow-up. Conclusion Despite modern prosthesis design and surgical technique, implant survival of lateral MB-UKR is lower than that of FB-UKR on the short- to mid-term due to bearing dislocation as the most common cause of failure. Since clinical results are equivalent in both groups, FB-UKR should be preferred in treatment of isolated lateral OA. Level of evidence Retrospective case–control study, Level III.

“…The findings of this study are consistent with the aforementioned systematic analyses, in which metal-backed FB-UKR showed lowest revision rates for lateral UKR [9,36].…”

Section: Discussionsupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Fixed-bearing is superior to mobile-bearing in lateral unicompartmental knee replacement: a retrospective matched-pairs analysis

Hariri

Zahn

Mick

et al. 2023

“…Similarly, in the previous study [19], aseptic implant loosening occurred in 3 patients, implant failure in 1 and polyethylene wear in 1 patient out of 236 patients at the end of a mean follow‐up of 14.9 ± 3.0 years. Other recent studies also showed excellent survivorship of TKA [6, 17]. This demonstrates quite well that sporting activities do not negatively impact survivorship of the knee prosthesis and all of our patients are encouraged to take up sports participation after their TKA.…”

Section: Discussionsupporting

confidence: 81%

Total knee arthroplasty improves sports activity and the patient-reported functional outcome at mid-term follow-up

Meena

Hoser

Abermann

et al. 2022

Self Cite

Purpose The purpose of this study was to assess (1) sports participation and preference for the type of sports activity after TKA, (2) mid-term functional outcome and activity level, (3) correlation of different age groups with activity level and functional outcomes, and (4) mid-term survivorship of the prosthesis. Methods A retrospective review of prospectively collected data was performed. 182 patients were included who underwent primary TKA between January 2010 and December 2016. Inclusion criteria were symptomatic knee osteoarthritis, age 50–90 years, and with a minimum of 5-year follow-up after TKA. Patients with rheumatoid arthritis and revision TKA were excluded. Sports participation and sports preference, Oxford Knee Score (OKS), Tegner Activity Level, and Visual Analogue Scale (VAS) for pain were recorded pre- and postoperatively at 6 months, 1 year, 2 years, and 5 years. The patient cohort was subdivided according to age groups; activity levels, patient-reported outcomes, and improvement in knee pain were correlated with these age groups. Kaplan–Meier curves were used to investigate survivorship at a minimum of 5 years. Results The mean age of the cohort was 75.6 ± 7.2 years (range 52–89). Significant improvement was noted in sports participation (p < 0.003). After TKA, there was no change in the preference for sports and none of the patients had to discontinue their sporting activity. OKS improved significantly at all follow-up time points compared to the preoperative score (p < .0001). Patients' sports and physical activity improved significantly at 1 year compared to the preoperative activity level (p < 0.001). Although the Tegner activity level improved over time, this improvement was not significant (NS), while it was significantly higher in males than in females (p < 0.004). Significant improvement was found in the VAS for pain at all follow-up time points compared to the preoperative score (p < .0001). Survivorship was found to be 100% at a 5-year follow-up. Conclusion After TKA, patients can be able to return to sporting activity or even perform better than before surgery. Maximum improvement was noted in the first post-operative year. The male and younger groups perform better than the female and older groups. Sports and physical activity do not negatively impact survivorship of the knee prosthesis at mid-term follow-up and all patients are encouraged to take up sports participation after their TKA. Level of evidence Level 3.

“…On the other hand, some authors believe that robotic systems may improve TKA survivorship which would result in a decreased cost for future revision. However, to date, there is a lack of conclusive data on the relationship between the use of robotic systems and the longevity of TKA implants [ 1 , 2 , 10 , 37 ]. Due to the additional time and expense associated with robotic systems in their long-term study, Kim 2019 et al [ 17 ] did not recommend widespread use of robotic TKA.…”

Section: Discussionmentioning

confidence: 99%

Complications and downsides of the robotic total knee arthroplasty: a systematic review

Nogalo

Meena

Abermann

et al. 2022

Self Cite

Purpose The purpose of this systematic review is to describe the complications and downsides of robotic systems in total knee arthroplasty (TKA). Methods A comprehensive search according to the PRISMA guidelines was performed across PubMed, MEDLINE, Cochrane Central Register of Controlled Trials, Scopus, and Google Scholar from inception until December 2021. All articles of any study design directly reporting on complications and downsides of the robotic system in TKA were considered for inclusion. Risk of bias assessment was performed for all included studies using the Cochrane risk of bias and MINORS score. Results A total of 21 studies were included, consisting of 4 randomized controlled trials, 7 prospective studies and 10 retrospective studies. Complications of the robotic system were pin-hole fracture, pin-related infection, iatrogenic soft tissue and bony injury, and excessive blood loss. While, downsides were longer operative duration, higher intraoperative cost, learning curve and aborting a robotic TKA due to different reasons. Iatrogenic injuries were more common in the active robotic system and abortion of the robotic TKA was reported only with active robotic TKA. Conclusion Robotic TKA is associated with certain advantages and disadvantages. Therefore, surgeons need to be familiar with the system to use it effectively. Widespread adoption of the robotic system should always be evidence-based. Level of evidence IV.