The Royal Orthopaedic Hospital, Birmingham, UK.
Musculoskeletal Research Unit, Translational Health Sciences, Bristol Medical School, Southmead Hospital, Bristol, UK.
Hip Int. 2022 Jul;32(4):493-500. doi: 10.1177/1120700020983297. Epub 2021 Jan 14.
Many worldwide regulatory authorities recommend regular surveillance of metal-on-metal hip arthroplasty patients given high failure rates. However, concerns have been raised about whether such regular surveillance, which includes asymptomatic patients, is evidence-based and cost-effective. We determined: (1) the cost of implementing the 2015 MHRA surveillance in "at-risk" Birmingham Hip Resurfacing (BHR) patients; and (2) how many asymptomatic hips with adverse reactions to metal debris (ARMD) would have been missed without patient recall.
All BHR patients eligible for the 2015 MHRA recall (all females, and males with head sizes ⩽46 mm, regardless of symptoms) at one centre were invited for review (hips = 707; patients = 593). All patients were investigated (Oxford Hip Score, radiographs, blood metal ions, and targeted cross-sectional imaging) and managed accordingly. Surveillance costs were calculated using finance department data.
The surveillance cost £105,921.79 (range £147.76-£257.50/patient). Radiographs (£39,598) and nurse practitioner time/assistance (£23,618) accounted for 60% of overall costs. 31 hips had ARMD on imaging (12 revised; 19 under surveillance). All revisions were symptomatic. 7 hips with ARMD under surveillance were asymptomatic and remain under regular review. The number needed to treat to avoid missing one asymptomatic ARMD case was 101 patients, representing a cost of £18,041 to avoid one asymptomatic case.
Implementing MHRA surveillance for "at-risk" BHR patients was extremely costly. The risk of asymptomatic ARMD was low with the BHR (1%), suggesting recommended follow-up in asymptomatic patients is not cost efficient. This raises concerns about the increasingly intensive surveillance recommended in the 2017 MHRA guidance for metal-on-metal hip patients.
鉴于金属对金属髋关节置换术的高失败率，许多国家的监管机构建议对该类患者进行定期监测。然而，人们对这种包括无症状患者的定期监测是否具有循证医学依据和成本效益提出了质疑。本研究旨在：（1）确定在一个中心对“有风险”的 Birmingham Hip Resurfacing（BHR）患者实施 2015 年英国药品和健康产品管理局（MHRA）监测的成本；（2）如果没有患者召回，将会错过多少无症状的金属颗粒不良反应（ARMD）髋关节。
对一家中心符合 2015 年 MHRA 召回条件的所有 BHR 患者（所有女性，以及头径 ⩽46mm 的男性，无论症状如何）进行了邀请（髋关节=707；患者=593）。所有患者均接受了检查（牛津髋关节评分、影像学、血液金属离子和有针对性的横断面成像），并根据检查结果进行了相应的处理。使用财务部数据计算了监测成本。
监测成本为 105921.79 英镑（范围为 147.76-257.50 英镑/患者）。X 线片（39598 英镑）和执业护士时间/协助（23618 英镑）占总费用的 60%。影像学检查发现 31 髋有 ARMD（12 髋进行了翻修；19 髋在监测中）。所有翻修的髋关节均有症状。19 髋在监测中的髋关节中，有 7 髋无症状，且仍在定期复查中。为避免漏诊 1 例无症状 ARMD 病例，需要治疗的患者数为 101 例，避免 1 例无症状病例的成本为 18041 英镑。
对“有风险”的 BHR 患者实施 MHRA 监测的成本非常高。BHR 发生无症状 ARMD 的风险较低（1%），这表明对无症状患者进行建议的随访并不具有成本效益。这引发了对 2017 年 MHRA 指导意见中对金属对金属髋关节置换患者进行的日益密集监测的质疑。
