Department of Physical Medicine and Rehabilitation, Elisabeth Bruyère Hospital-Ottawa, 43 Bruyère St, K1N 5C8 Ontario, ON, Canada.
University of Leeds and NIHR Leeds Musculoskeletal Biomedical Research Unit, Leeds, UK.
Ann Phys Rehabil Med. 2021 Mar;64(2):101439. doi: 10.1016/j.rehab.2020.09.005. Epub 2021 Mar 9.
Knee joint osteoarthritis (OA) is often accompanied by flexion contracture (FC), but the impact of FC on important outcomes across the spectrum of OA, such as the incidence, progression and need for total knee arthroplasty (TKA), is not well established.
We evaluated whether the presence and/or severity of knee FC were risk factors for worse OA clinical outcomes, radiographic incidence and progression as well as time to TKA.
We evaluated longitudinal 9-year data from the Osteoarthritis Initiative (OAI) database for 3 sub-cohorts: at-risk of knee OA (n=3284), radiographically established knee OA (n=1390), and low-risk controls (n=122). We classified knee FC as none, mild, moderate or severe based on knee extension at enrolment. Knee OA outcomes were extracted from the database.
FC was present in 32.4% of knees. Participants with FC had increased knee OA incidence with joint space narrowing in the definition (corrected odds ratio 1.31 [95% confidence interval (CI) 1.04-1.64]). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for pain, stiffness and function were worse with than without FC at nearly all times (p<0.001). Effect estimates were significant for all 3 WOMAC sub-scales comparing FC to no FC (pain: 0.15 [95% CI 0.02-0.28], stiffness: 0.11 [0.05-0.18], function: 0.49 [0.05-0.93]). Individuals with knee FC had higher Kellgren and Lawrence grade (effect size 0.31 [95% CI 0.25-0.37]) and were more likely to undergo TKA (corrected odds ratio 1.37 [95% CI 1.10-1.71]) than those without FC. All outcomes were worse with increasing FC severity.
The presence of knee FC at enrolment was a risk factor for radiographic OA incidence including joint space narrowing, worse clinical outcomes, radiographic progression and the need for early TKA. Treatment of knee FC may represent an option across the OA spectrum. Further research is needed to evaluate the pathophysiology, joint structure alterations and longitudinal impact of treating FC in individuals with knee OA.
膝关节骨关节炎（OA）常伴有屈曲挛缩（FC），但 FC 对 OA 各谱中重要结局的影响，如发生率、进展和全膝关节置换术（TKA）的需求，尚未得到很好的确定。
我们评估膝关节 FC 的存在和/或严重程度是否是膝关节 OA 临床结局恶化、放射学发生率和进展以及 TKA 时间的危险因素。
我们评估了 Osteoarthritis Initiative（OAI）数据库的 9 年纵向数据，该数据来自 3 个亚队列：膝关节 OA 高危（n=3284）、放射学确诊膝关节 OA（n=1390）和低危对照组（n=122）。我们根据入组时的膝关节伸展程度将膝关节 FC 分为无、轻度、中度或重度。从数据库中提取膝关节 OA 结局。
32.4%的膝关节存在 FC。FC 组的膝关节 OA 发生率更高，关节间隙变窄的校正比值比为 1.31（95%置信区间（CI）1.04-1.64）。在几乎所有时间，有 FC 的患者的 Western Ontario and McMaster Universities Osteoarthritis Index（WOMAC）疼痛、僵硬和功能评分都比没有 FC 的患者差（p<0.001）。与无 FC 相比，所有 3 个 WOMAC 亚量表的 FC 比较的效应估计均有统计学意义（疼痛：0.15[95%CI 0.02-0.28]，僵硬：0.11[0.05-0.18]，功能：0.49[0.05-0.93]）。有膝关节 FC 的患者的 Kellgren 和 Lawrence 分级更高（效应量 0.31[95%CI 0.25-0.37]），更有可能接受 TKA（校正比值比 1.37[95%CI 1.10-1.71]），而没有 FC 的患者则不然。FC 程度的增加与所有结局的恶化有关。
入组时膝关节 FC 的存在是放射学 OA 发生率的危险因素，包括关节间隙变窄、临床结局恶化、放射学进展和早期 TKA 的需求。治疗膝关节 FC 可能是 OA 各谱中的一种选择。需要进一步研究以评估膝关节 OA 患者 FC 的病理生理学、关节结构改变和治疗的纵向影响。
