Tração femorotibial mecânica alivia dor em pacientes com osteoartrite de joelho: um ensaio clínico aleatorizado

Abstract

Introduction: Knee osteoarthritis (KOA) is a chronic progressive joint disease that affects all articular elements of the knee and is associated with obesity and aging. Pain and stiffness are the main symptoms of KOA, impacting functional capacity and quality of life. Mechanical femorotibial traction (MFTT) is an effective therapeutic procedure for KOA, promoting immediate pain reduction. The scientific literature presents several MFTT loads, but no study has investigated the most efficient one. Objective: To compare the immediate effects of 15kg and 30kg MFTT loads on pain and functional capacity measures in people with KOA. Methods: This is a randomized, double-blind, two-arm parallel clinical trial, written based on the “Consolidated Standards of Reporting Trials” (CONSORT) guideline. The immediate and isolated effect of 15 kg (MFTT-15) and 30 kg (MFTT-30) loads of MFTT applied continuously for 15 minutes was measured. The outcomes evaluated were: pain intensity (Numerical Pain Scale - NPS); functional capacity (Timed Up and Go - TUG); range of motion (ROM) of flexion and hyperextension (Knee Extension Prone Test - KEPT) of the knee; and joint space width (JSW) (obtained with an imaging ultrasound). Descriptive statistics were used to characterize the sample; inferential statistics, with a mixed linear model modeled with fixed effects, were used to compare the effects of the treatment. The effect size (Hedges' g) was calculated for differences with a significance level of p ≤ 0.05. Results: Fifty people with KOA (36 women, 72%) participated in this study, 25 in each group: MFTT-15 (mean age: 62.5±9.3) and MFTT-30 (mean age: 59.4±9.7). The mean intergroup difference in the primary outcomes was significant in pain intensity [0.96 points (95% CI: 0.53– 1.86)], but not in functional capacity [0.08s (95% CI: -2.22–2.40)]. In the secondary outcomes, this mean difference was only significant in LEA [0.04cm (95% CI: 0.01–0.06)]. Conclusion: The immediate isolated effect of the 15 kg load of MFTT used in the treatment of patients with KOA is superior to that of the 30 kg load on the clinical outcome of pain intensity but does not present a significant difference on the outcome of functional capacity.