Section of Rheumatology, Boston University School of Medicine, Massachusetts.
School of Public Health, Boston University, Massachusetts.
Arthritis Rheumatol. 2023 Jul;75(7):1132-1138. doi: 10.1002/art.42454. Epub 2023 Apr 26.
Although magnetic resonance imaging (MRI) is the imaging modality of choice for research, there is no widely accepted MRI definition of knee osteoarthritis (OA). We undertook this study to test the performance of different MRI definitions of OA.
We studied Multicenter Osteoarthritis Study participants with knee symptoms using posteroanterior and lateral knee radiographs and MRIs. Radiographic OA was defined as Kellgren/Lawrence grade ≥2 in the tibiofemoral (TF) and/or patellofemoral (PF) joint. Symptomatic OA was defined using a validated questionnaire. MRI findings of cartilage damage, osteophytes, bone marrow lesions (BMLs), and synovitis were scored using the Whole-Organ MRI Score system. We compared definitions using combinations of MRI features to the validation criteria of prevalent radiographic OA and symptomatic OA. All combinations included cartilage damage score ≥2 (0-6 scale) and osteophyte score ≥2 (0-6 scale); addition of BMLs and synovitis score was also tested. We also evaluated a Delphi panel definition that defined OA differently for the PF and TF joints. For each definition, we calculated sensitivity, specificity, and the area under the curve (AUC).
We included 1,185 knees from 1,185 participants (mean age 66 years, 62% female, 89% White). Among the 1,185 knees, 482 knees had radiographic OA, and 524 knees had symptomatic OA. The MRI definitions with a cartilage score ≥2 and osteophyte score ≥2 and definitions which added BMLs or synovitis score ≥1 had the highest sensitivities (95.2% and 94.5%, respectively) for prevalent radiographic OA (AUCs 0.67 and 0.69, respectively), and also had the highest sensitivities for symptomatic OA. The Delphi panel definition had similar performance but was more complex to apply.
An MRI OA definition requiring cartilage damage and a small osteophyte with or without BMLs or synovitis had the best performance and was simplest for identifying radiographic OA and symptomatic OA.
尽管磁共振成像（MRI）是研究中首选的成像方式，但目前还没有被广泛接受的膝关节骨关节炎（OA）MRI 定义。我们进行这项研究是为了测试不同的 OA MRI 定义的性能。
我们使用膝关节前后位和侧位 X 线片和 MRI 研究了多中心骨关节炎研究参与者的膝关节症状。放射学 OA 定义为在胫股（TF）和/或髌股（PF）关节中 Kellgren/Lawrence 分级≥2。症状性 OA 使用经过验证的问卷定义。使用全器官 MRI 评分系统对软骨损伤、骨赘、骨髓病变（BML）和滑膜炎的 MRI 发现进行评分。我们比较了使用 MRI 特征组合的定义与现患放射学 OA 和症状性 OA 的验证标准。所有组合均包括软骨损伤评分≥2（0-6 分）和骨赘评分≥2（0-6 分）；还测试了添加 BML 和滑膜炎评分。我们还评估了一个 Delphi 小组定义，该定义对 PF 和 TF 关节的 OA 定义不同。对于每个定义，我们计算了敏感性、特异性和曲线下面积（AUC）。
我们纳入了 1185 名参与者的 1185 个膝关节（平均年龄 66 岁，62%为女性，89%为白人）。在 1185 个膝关节中，482 个膝关节有放射学 OA，524 个膝关节有症状性 OA。具有软骨评分≥2 和骨赘评分≥2 且添加 BML 或滑膜炎评分≥1 的 MRI 定义具有最高的现患放射学 OA 敏感性（分别为 95.2%和 94.5%）（AUC 分别为 0.67 和 0.69），也具有最高的症状性 OA 敏感性。德尔菲小组的定义具有相似的表现，但应用起来更为复杂。
需要软骨损伤和小骨赘，伴有或不伴有 BML 或滑膜炎的 MRI OA 定义具有最佳性能，并且最适合识别放射学 OA 和症状性 OA。
