Department of Orthopaedic Surgery, Diakovere Annastift, Medical School Hannover, Anna-von-Borries-Str. 1-7, 30161, Hannover, Germany.
Knee Surg Sports Traumatol Arthrosc. 2020 Jul;28(7):2082-2090. doi: 10.1007/s00167-020-05912-x. Epub 2020 Mar 6.
The purpose of this study was to examine the predictive value concerning clinical outcome and implant survival, as well as the accuracy of individual tests of a recently published radiographic decision aid for unicondylar knee arthroplasty indication findings.
In the retrospective part of the study, 98 consecutive patients who had undergone unicondylar knee arthroplasty (Phase 3 Oxford medial UKA) were included, using revision questionnaires, as well as the Forgotten Joint Score-12 (FJS-12) and Knee Osteoarthritis Outcome Score (KOOS) and analysed for suitability of the radiographic decision aid. Inappropriate and appropriate indications were then compared concerning the clinical outcome and implant survival. The prospective part of the study assessed the accuracy of the decision aid's radiographic tests (varus and valgus stress views, true lateral view and skyline view), and included 90 patients. Definition as appropriate for UKA procedure included medial bone-on-bone situation in varus stress views, full-thickness lateral cartilage and functional medial collateral ligament in valgus stress views, functional anterior cruciate ligament (ACL) in true lateral views and absence of lateral facet osteoarthritis with bone loss in skyline views. Pre-operative radiographic assessment with respect to the decision aid was then compared with intraoperative articular conditions. The clinical outcome was analysed using non-parametric tests (Mann-Whitney U), and revision rates were compared using the Fisher's exact test. Accuracy assessment included calculations of the sensitivity, specificity, negative predictive value and positive predictive value. A p value < 0.05 was considered statistically significant.
Appropriate unicondylar knee arthroplasty with respect to the decision aid showed a significantly lower revision rate compared to inappropriate unicondylar knee arthroplasty (7.3% vs. 50.0%, p < 0.0001), as well as higher clinical outcome scores (FJS-12: 53.13 vs. 31.25, p = 0.041 and KOOS-QDL: 68.75 vs. 50.0, p = 0.036). The overall sensitivity (70.1%) and specificity (76.2%) for the radiographic decision aid was comparably low, which was essentially based on false negative cases (22.7%) regarding medial bone-to-bone conditions.
The radiographic decision aid is a helpful tool to predict clinical outcome and implant survival of mobile-bearing unicondylar knee arthroplasty. Strict use of the radiographic decision aid may lead to increased exclusion of appropriate patients with unicondylar knee arthroplasty implantation.
本研究旨在探讨一种新发布的单髁膝关节置换术适应证影像学决策辅助工具的预测价值，包括临床结果和植入物存活率，以及各项检查的准确性。
在研究的回顾性部分，纳入了 98 例接受单髁膝关节置换术（3 期牛津内侧 UKA）的连续患者，使用修订后的问卷调查以及遗忘关节评分-12 分（FJS-12）和膝关节骨关节炎评分（KOOS）进行分析，以评估影像学决策辅助工具的适用性。然后比较影像学决策辅助工具下不适当和适当的适应证与临床结果和植入物存活率的关系。研究的前瞻性部分评估了决策辅助工具影像学检查（内翻和外翻应力位、标准侧位和关节上间隙位）的准确性，纳入了 90 例患者。UKA 手术适应证的定义包括内翻应力位的内侧骨对骨情况、外翻应力位的全层外侧软骨和功能内侧副韧带、标准侧位的功能前交叉韧带（ACL）以及关节上间隙位无外侧关节面骨关节炎和骨丢失。然后比较术前影像学评估与术中关节状况。使用非参数检验（Mann-Whitney U 检验）分析临床结果，使用 Fisher 确切概率法比较翻修率。准确性评估包括灵敏度、特异度、阴性预测值和阳性预测值的计算。p 值＜0.05 被认为具有统计学意义。
影像学决策辅助工具下的适当单髁膝关节置换术与不适当单髁膝关节置换术相比，翻修率显著降低（7.3% vs. 50.0%，p＜0.0001），临床结果评分也更高（FJS-12：53.13 分 vs. 31.25 分，p=0.041；KOOS-QDL：68.75 分 vs. 50.0 分，p=0.036）。影像学决策辅助工具的整体灵敏度（70.1%）和特异度（76.2%）相对较低，主要是因为内侧骨对骨情况的假阴性病例（22.7%）。
该影像学决策辅助工具有助于预测单髁膝关节置换术的临床结果和植入物存活率。严格使用影像学决策辅助工具可能会导致适当的单髁膝关节置换术患者被排除在外。
