Vargas E Silva Natália Cristina de Oliveira, Dos Anjos Rafael Luz, Santana Matheus Miranda Campos, Battistella Linamara Rizzo, Marcon Alfieri Fábio
Adventist University of São Paulo (UNASP), Brazil.
School of Medicine, University of São Paulo, Brazil.
Reumatologia. 2020;58(6):375-380. doi: 10.5114/reum.2020.102002. Epub 2020 Dec 23.
Knee pain is an imprecise marker of radiographic evidence of osteoarthritis (OA). These patients are more likely to develop central sensitisation to pain, a risk factor for chronic pain.
The aim of this study was to examine the associations among radiographic evidence of OA, self-reported pain, pressure pain thresholds (PPT), and superficial knee temperature in individuals with knee OA.
This cross-sectional study enrolled 25 patients with knee OA with clinic and radiographic diagnosis of bilateral OA (Kellgren-Lawrence grading scale 1-4 in X-ray images), but symptoms of pain and discomfort in only one of the knees, with pain perception in the symptomatic knee equal to or above 4 in a visual analogue scale. Volunteers underwent an evaluation including demographic data, superficial knee temperature (infrared thermography, mean superficial temperature of the region of the knee) and PPT (digital algometry at longus adductor, vastus lateralis, vastus medialis and tibialis anterior muscles, patellar tendon, and centre of the patella).
Comparisons between symptomatic and asymptomatic knees revealed no differences regarding Kellgren-Lawrence classification, knee superficial temperature, or PPT. Significant weak and moderate associations were found between radiographic classification of OA and PPT of both knees in almost all sites evaluated. Nonetheless, superficial temperature of the knee was not associated with PPT or Kellgren-Lawrence grading scale.
Patients with bilateral knee OA presented no differences in symptomatic and asymptomatic knees regarding radiographic evidence, knee temperature, and PPT, indicating that central sensitisation may be present in them. Radiographic classification of OA was significantly associated with PPT in both knees.
膝关节疼痛是骨关节炎（OA）影像学证据的一个不精确指标。这些患者更有可能发展为对疼痛的中枢敏化，这是慢性疼痛的一个危险因素。
本研究的目的是检查膝关节OA患者中OA的影像学证据、自我报告的疼痛、压痛阈值（PPT）和膝关节表面温度之间的关联。
这项横断面研究纳入了25例膝关节OA患者，这些患者经临床和影像学诊断为双侧OA（X线图像上的Kellgren-Lawrence分级为1-4级），但仅一侧膝关节有疼痛和不适症状，且症状性膝关节的疼痛感知在视觉模拟量表上等于或高于4分。志愿者接受了包括人口统计学数据、膝关节表面温度（红外热成像，膝关节区域的平均表面温度）和PPT（在内收长肌、股外侧肌、股内侧肌和胫骨前肌、髌腱和髌骨中心进行数字测痛法）的评估。
有症状和无症状膝关节之间的比较显示，在Kellgren-Lawrence分类、膝关节表面温度或PPT方面没有差异。在几乎所有评估部位，OA的影像学分类与双膝的PPT之间均发现了显著的弱关联和中度关联。然而，膝关节表面温度与PPT或Kellgren-Lawrence分级量表无关。
双侧膝关节OA患者在有症状和无症状膝关节的影像学证据、膝关节温度和PPT方面没有差异，这表明他们可能存在中枢敏化。OA的影像学分类与双膝的PPT显著相关。
