Department of General Practice, Erasmus MC Medical University Center Rotterdam, Rotterdam, the Netherlands.
Centre for Hip Health and Mobility, Department of Family Practice, University of British, Columbia, Canada.
Am J Sports Med. 2018 Nov;46(13):3217-3226. doi: 10.1177/0363546518801314. Epub 2018 Oct 15.
Patellofemoral malalignment has been observed among people with patellofemoral pain (PFP) and may be associated with the presence of imaging features of osteoarthritis, symptoms, and function.
To determine whether patellofemoral joint alignment and bony shape are associated with (1) cartilage, bone, and soft tissue morphological abnormalities defined on magnetic resonance imaging (MRI) and (2) reported symptoms and function among people with PFP.
Cross-sectional study; Level of evidence, 3.
Participants (mean ± SD age, 30.2 ± 9.5 years; range, 14-50 years; 78 females, 58.6%) completed questionnaires regarding demographics, pain, symptoms, and function and underwent a 3-T MRI scan of their more symptomatic eligible knee. Structural MRI abnormalities were scored with the MOAKS (Magnetic Resonance Imaging Osteoarthritis Knee Score), and MRI alignment and shape were measured with standardized methods. Associations among MOAKS features, PFP symptoms, and alignment and shape measures were evaluated with regression analyses (α = .05).
Minor cartilage defects were present in 22 (16.5%) participants, patellar osteophytes in 83 (62.4%), anterior femur osteophytes in 29 (21.8%), Hoffa synovitis in 81 (60.9%), and prefemoral fat pad synovitis in 49 (36.8%). A larger Insall-Salvati ratio was significantly associated with the presence of patellar osteophytes (odds ratio [OR], 51.82; 95% CI, 4.20-640.01), Hoffa synovitis (OR, 60.37; 95% CI, 4.66-782.61), and prefemoral fat pad synovitis (OR, 43.31; 95% CI, 4.28-438.72) in the patellofemoral joint. A larger patellar tilt angle was significantly associated with the presence of minor cartilage defects (OR, 1.10; 95% CI, 1.00-1.20), the presence of patellar osteophytes (OR 1.12; 95%CI 1.02-1.22), and prefemoral fat pad synovitis (OR, 1.11; 95% CI, 1.03-1.20) in the patellofemoral joint. Finally, a larger bisect offset was significantly associated with the presence of minor cartilage defects (OR, 1.05; 95% CI, 1.00-1.11) and patellar osteophytes (OR, 1.07; 95% CI, 1.01-1.14) in the patellofemoral joint. The majority of patellofemoral alignment measures were not associated with symptoms or function.
For people with PFP, the presence of morphological abnormalities defined on MRI appears to be related to particular patellofemoral alignment measures, including higher Insall-Salvati ratio (indicating patella alta), larger patellar tilt angle (indicating greater lateral tilt), and larger bisect offset (indicating greater lateral displacement). Hardly any associations were found with symptoms or function. So there might be a distinct subgroup of PFP that is more prone to developing patellofemoral osteoarthritis later in life, as particular alignment measures seem to be associated with the presence of patellar osteophytes. Prospective studies are required to investigate the longitudinal relationship between alignment or bony shape and morphological abnormalities defined on MRI in this patient population.
髌股疼痛（PFP）患者中存在髌股对线不良，并且可能与骨关节炎的影像学特征、症状和功能有关。
确定髌股关节对线和骨形状是否与（1）磁共振成像（MRI）上定义的软骨、骨和软组织形态异常，以及（2）PFP 患者的报告症状和功能相关。
横断面研究；证据水平，3 级。
参与者（平均±标准差年龄，30.2±9.5 岁；年龄范围 14-50 岁；78 名女性，58.6%）完成了关于人口统计学、疼痛、症状和功能的问卷调查，并对其更有症状的合格膝关节进行了 3-T MRI 扫描。结构 MRI 异常采用 MOAKS（磁共振成像骨关节炎膝关节评分）进行评分，MRI 对线和形状采用标准化方法进行测量。使用回归分析（α=.05）评估 MOAKS 特征、PFP 症状与对线和形状测量之间的相关性。
22 名（16.5%）参与者存在小的软骨缺损，83 名（62.4%）存在髌骨关节骨赘，29 名（21.8%）存在股骨前骨赘，81 名（60.9%）存在 Hoffa 滑膜炎，49 名（36.8%）存在髌前脂肪垫滑膜炎。Insall-Salvati 比值越大，髌骨关节骨赘（比值比 [OR]，51.82；95%置信区间，4.20-640.01）、Hoffa 滑膜炎（OR，60.37；95%置信区间，4.66-782.61）和髌前脂肪垫滑膜炎（OR，43.31；95%置信区间，4.28-438.72）的存在更为显著。髌股倾斜角越大，存在小的软骨缺损（OR，1.10；95%置信区间，1.00-1.20）、髌骨关节骨赘（OR，1.12；95%置信区间，1.02-1.22）和髌前脂肪垫滑膜炎（OR，1.11；95%置信区间，1.03-1.20）的可能性越大。最后，双分割偏移越大，存在小的软骨缺损（OR，1.05；95%置信区间，1.00-1.11）和髌骨关节骨赘（OR，1.07；95%置信区间，1.01-1.14）的可能性越大。大多数髌股对线测量与症状或功能无关。
对于 PFP 患者，MRI 上定义的形态异常似乎与特定的髌股对线测量有关，包括较高的 Insall-Salvati 比值（表明髌股高位）、较大的髌股倾斜角（表明更大的外侧倾斜）和较大的双分割偏移（表明更大的外侧移位）。几乎没有发现与症状或功能的关联。因此，可能存在一个特定的 PFP 亚组，更容易在以后的生活中发展为髌股骨关节炎，因为特定的对线测量似乎与髌骨关节骨赘的存在有关。需要前瞻性研究来研究该患者人群中髌股对线或骨形状与 MRI 上定义的形态异常之间的纵向关系。
