Abugu Glory Uche, Holloway Nicholas, Riches Philip, Clarke Jon, Giardini Mario Ettore, Chopra Swati
University of Strathclyde, Department of Biomedical Engineering, Glasgow, UK; Department of Orthopaedics, Golden Jubilee University National Hospital, Clydebank, UK.
Department of Orthopaedics, Golden Jubilee University National Hospital, Clydebank, UK.
J Clin Epidemiol. 2025 Sep;185:111897. doi: 10.1016/j.jclinepi.2025.111897. Epub 2025 Jul 7.
This study aimed to estimate patient acceptable symptom state (PASS) thresholds in the Forgotten Joint Score (FJS) 1 year following primary total knee arthroplasty (PTKA) while investigating the impact of patients' characteristics on PASS thresholds.
This cohort study used data from patients who underwent PTKA at a public hospital in Scotland between April 2021 and December 2022. Assessment of FJS (0-100, high-low knee awareness) was completed 1 year postoperatively. A single-item question about satisfaction with the operated knee was completed at 1 year and served as the anchor for estimating PASS thresholds. Anchor-based predictive modeling (adjusted and unadjusted) and receiver operating characteristic (ROC) curve methods were used to determine PASS thresholds. The impact of patient characteristics on PASS threshold values was investigated by calculating stratified PASS values based on gender and age groups.
A total of 1832 PTKAs were performed between April 2021 and December 2022, of which 1359 (74%) had complete data comprising the study cohort. The median age and body mass index of patients included in the study were 70 years and 31.2 kg/m, respectively, with 54% being females. The proportion of satisfied patients was 84%. A moderate positive correlation between FJS and patient satisfaction was found (r = 0.64, P < .001), which supports the validity of the external anchor. PASS thresholds for the entire cohort were 31 (ROC method) and ∼33 points (predictive modeling method). Larger PASS values were found for male patients and patients aged ≥70 years compared to their female and younger counterparts. The adjusted predictive modeling estimate was 15.3; given that the data do not meet the assumption of normal distribution, we consider this threshold might be biased and must be interpreted with circumspection.
A postoperative FJS of ≥33 points can be used as a reference guide to evaluate successful achievement of a "forgotten joint" in a Scottish population. Patients' characteristics impact PASS estimates and should be considered when interpreting outcome scores.
After knee replacement surgery, patients want their new knee to feel natural. The FJS measures how much a person notices their artificial knee in daily life. The score goes from 0 to 100, with higher numbers meaning the knee feels more natural. We studied data from over 1300 patients in Scotland using modern statistical methods. Our results show that most patients need a score of at least 33 to feel satisfied with their knee 1 year after surgery, while men and people aged ≥70 years seem to need higher scores.
本研究旨在评估初次全膝关节置换术（PTKA）1年后遗忘关节评分（FJS）中的患者可接受症状状态（PASS）阈值，同时研究患者特征对PASS阈值的影响。
本队列研究使用了2021年4月至2022年12月期间在苏格兰一家公立医院接受PTKA的患者数据。术后1年完成FJS评估（0 - 100分，高低膝关节感知度）。术后1年完成一个关于对手术膝关节满意度的单项问题，并将其作为估计PASS阈值的锚点。采用基于锚点的预测建模（调整和未调整）以及受试者工作特征（ROC）曲线方法来确定PASS阈值。通过计算基于性别和年龄组的分层PASS值，研究患者特征对PASS阈值的影响。
2021年4月至2022年12月期间共进行了1832例PTKA手术，其中1359例（74%）有完整数据纳入研究队列。纳入研究的患者中位年龄和体重指数分别为70岁和31.2kg/m²，女性占54%。满意患者的比例为84%。发现FJS与患者满意度之间存在中度正相关（r = 0.64，P < 0.001），这支持了外部锚点的有效性。整个队列的PASS阈值通过ROC方法为31分，通过预测建模方法约为33分。与女性和年轻患者相比，男性患者和年龄≥70岁的患者的PASS值更高。调整后的预测建模估计值为15.3；鉴于数据不满足正态分布假设，我们认为这个阈值可能存在偏差，必须谨慎解释。
术后FJS≥33分可作为评估苏格兰人群中“遗忘关节”成功达成情况的参考指南。患者特征会影响PASS估计，在解释结果评分时应予以考虑。
膝关节置换手术后，患者希望他们的新膝关节感觉自然。FJS衡量一个人在日常生活中对其人工膝关节的注意程度。分数从0到100，分数越高意味着膝关节感觉越自然。我们使用现代统计方法研究了来自苏格兰1300多名患者的数据。我们的结果表明，大多数患者在术后1年需要至少33分才能对其膝关节感到满意，而男性和年龄≥70岁的人似乎需要更高的分数。
