Association of the peripheral and central pressure pain threshold with the parameters of adiposity of the lower limbs in knee osteoarthritis in obese and non-obese subjects obese

Abstract

The present project aims to associate the peripheral and central pressure pain threshold with adiposity parameters, in subjects with knee osteoarthritis (KOA), who are obese and not obese. For this, 30 subjects with KOA will be recruited, with degrees II, III and IV (Kellgren & Lawrence) divided into two groups: (1) Obese (n=15), with BMI e 30 and (2) Non-obese (n =15), with a BMI < 30. All subjects will be submitted to bilateral knee X-ray examinations, with the personal data of the participants being collected through a self-administered form, and anthropometric measurements will also be taken, such as weight and height, abdominal circumference and hip and blood pressure will be measured. To determine the pressure pain threshold of the participants, a digital pressure algometer will be used, with the pressure stimulus being applied to the medial joint line of the ipsilateral knee and to the contralateral thenar eminence. Finally, for the analysis of the appendicular fat of the lower limbs, the participants will be submitted to the Dual Energy X-Ray Absorptiometry (DXA) examination, being subsequently carried out an analysis of the regions of interest. For data analysis, a descriptive analysis of the variables will be carried out and the normality and homogeneity of variances will be verified. According to the distribution of the data, the corresponding independent or non-parametric t-test will be applied. To investigate the prediction of peripheral and central pain symptoms, two multiple linear regression models will be applied, the first considering the percentage of fat in the ROI as the dependent variable and peripheral and central pain as independent variables. In the second regression model, the total percentage of adiposity of the lower appendicular limbs will be considered as the dependent variable, and the pain threshold points will be considered, in order to identify the influence of the independent variables. For all analyzes an alpha of 5% (p d 0.05) will be adopted.