Nuffield Department of Orthopaedics, University of Oxford, Oxford, UK.
Health Services Research Unit, University of Aberdeen, Aberdeen, UK.
Health Technol Assess. 2020 Apr;24(20):1-98. doi: 10.3310/hta24200.
Late-stage medial compartment knee osteoarthritis can be treated using total knee replacement or partial (unicompartmental) knee replacement. There is high variation in treatment choice and insufficient evidence to guide selection.
To assess the clinical effectiveness and cost-effectiveness of partial knee replacement compared with total knee replacement in patients with medial compartment knee osteoarthritis. The findings are intended to guide surgical decision-making for patients, surgeons and health-care providers.
This was a randomised, multicentre, pragmatic comparative effectiveness trial that included an expertise component. The target sample size was 500 patients. A web-based randomisation system was used to allocate treatments.
Twenty-seven NHS hospitals (68 surgeons).
Patients with medial compartment knee osteoarthritis.
The trial compared the overall management strategy of partial knee replacement treatment with total knee replacement treatment. No specified brand or subtype of implant was investigated.
The Oxford Knee Score at 5 years was the primary end point. Secondary outcomes included activity scores, global health measures, transition items, patient satisfaction (Lund Score) and complications (including reoperation, revision and composite 'failure' - defined by minimal Oxford Knee Score improvement and/or reoperation). Cost-effectiveness was also assessed.
A total of 528 patients were randomised (partial knee replacement, = 264; total knee replacement, = 264). The follow-up primary outcome response rate at 5 years was 88% and both operations had good outcomes. There was no significant difference between groups in mean Oxford Knee Score at 5 years (difference 1.04, 95% confidence interval -0.42 to 2.50). An area under the curve analysis of the Oxford Knee Score at 5 years showed benefit in favour of partial knee replacement over total knee replacement, but the difference was within the minimal clinically important difference [mean 36.6 (standard deviation 8.3) ( = 233), mean 35.1 (standard deviation 9.1) ( = 231), respectively]. Secondary outcome measures showed consistent patterns of benefit in the direction of partial knee replacement compared with total knee replacement although most differences were small and non-significant. Patient-reported improvement (transition) and reflection (would you have the operation again?) showed statistically significant superiority for partial knee replacement only, but both of these variables could be influenced by the lack of blinding. The frequency of reoperation (including revision) by treatment received was similar for both groups: 22 out of 245 for partial knee replacement and 28 out of 269 for total knee replacement patients. Revision rates at 5 years were 10 out of 245 for partial knee replacement and 8 out of 269 for total knee replacement. There were 28 'failures' of partial knee replacement and 38 'failures' of total knee replacement (as defined by composite outcome). Beyond 1 year, partial knee replacement was cost-effective compared with total knee replacement, being associated with greater health benefits (measured using quality-adjusted life-years) and lower health-care costs, reflecting lower costs of the index surgery and subsequent health-care use.
It was not possible to blind patients in this study and there was some non-compliance with the allocated treatment interventions. Surgeons providing partial knee replacement were relatively experienced with the procedure.
Both total knee replacement and partial knee replacement are effective, offer similar clinical outcomes and have similar reoperation and complication rates. Some patient-reported measures of treatment approval were significantly higher for partial knee replacement than for total knee replacement. Partial knee replacement was more cost-effective (more effective and cost saving) than total knee replacement at 5 years.
Further (10-year) follow-up is in progress to assess the longer-term stability of these findings.
Current Controlled Trials ISRCTN03013488 and ClinicalTrials.gov NCT01352247.
This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in ; Vol. 24, No. 20. See the NIHR Journals Library website for further project information.
晚期膝关节内侧间室骨关节炎可采用全膝关节置换或单髁膝关节置换治疗。治疗选择存在很大差异，且缺乏指导选择的充分证据。
评估内侧间室骨关节炎患者行单髁膝关节置换与全膝关节置换的临床效果和成本效果。研究结果旨在为患者、外科医生和医疗保健提供者的手术决策提供指导。
这是一项随机、多中心、实用比较有效性试验，包括一个专业知识组成部分。目标样本量为 500 例患者。使用基于网络的随机化系统分配治疗方法。
27 家 NHS 医院（68 名外科医生）。
内侧间室骨关节炎患者。
试验比较了单髁膝关节置换治疗与全膝关节置换治疗的总体管理策略。未研究特定品牌或亚类植入物。
5 年时的牛津膝关节评分是主要终点。次要结局包括活动评分、总体健康指标、转移项目、患者满意度（Lund 评分）和并发症（包括再手术、翻修和复合“失败”——定义为最小牛津膝关节评分改善和/或再手术）。还评估了成本效果。
共随机分配了 528 例患者（单髁膝关节置换组，n=264；全膝关节置换组，n=264）。5 年时的主要结局随访应答率为 88%，两种手术均有良好的效果。两组在 5 年时的平均牛津膝关节评分无显著差异（差值 1.04，95%置信区间 -0.42 至 2.50）。5 年时牛津膝关节评分的曲线下面积分析显示，单髁膝关节置换优于全膝关节置换，但差异在最小临床重要差异范围内[平均 36.6（标准差 8.3）（n=233），平均 35.1（标准差 9.1）（n=231）]。次要结局测量指标显示，单髁膝关节置换的方向与全膝关节置换相比，均有一致的获益模式，尽管大多数差异较小且无统计学意义。患者报告的改善（转移）和反思（会再次接受手术吗？）仅显示单髁膝关节置换具有统计学上的优越性，但这两个变量都可能受到缺乏盲法的影响。根据所接受的治疗，两组的再手术（包括翻修）频率相似：单髁膝关节置换组 22 例，全膝关节置换组 28 例。5 年时的翻修率分别为单髁膝关节置换组 10 例，全膝关节置换组 8 例。单髁膝关节置换组有 28 例“失败”，全膝关节置换组有 38 例“失败”（按复合结局定义）。1 年后，单髁膝关节置换与全膝关节置换相比具有成本效果，具有更大的健康效益（使用质量调整生命年来衡量）和更低的医疗保健成本，反映出索引手术和后续医疗保健使用的成本较低。
本研究无法对患者进行盲法，存在一定程度的不遵守分配的治疗干预措施。提供单髁膝关节置换的外科医生相对经验丰富。
全膝关节置换和单髁膝关节置换均有效，提供相似的临床结果，且再手术和并发症发生率相似。一些治疗批准的患者报告测量指标对单髁膝关节置换的评价明显高于全膝关节置换。5 年时，单髁膝关节置换比全膝关节置换更具成本效果（更有效且节省成本）。
正在进行进一步（10 年）随访，以评估这些发现的长期稳定性。
当前对照试验 ISRCTN03013488 和临床试验。gov NCT01352247。
本项目由英国国家卫生研究院（NIHR）健康技术评估计划资助，将在 ; Vol. 24, No. 20 中全文发表。有关该项目的更多信息，请访问 NIHR 期刊库网站。
