Inflammatory biomarkers, endogenous analgesia and gait characteristics in those with moderate medial compartment knee osteoarthritis who experience increased pain after 30 minutes of continuous walking

Abstract

Purpose: Walking is recommended for those with knee osteoarthritis (OA) to improve pain; however, numerous reports of increased pain after walking exist following short durations of activity. The purpose of this study was to quantify the concurrent response of inflammatory biomarkers, endogenous analgesia and gait biomechanics to 30 minutes of physical activity across individuals with varied pain responses. The hypothesis was that those with medial compartment knee OA who self-reported an increase in pain following a 30-min walk would have a greater increase in inflammatory biomarkers, less increase in endogenous analgesia and a gait pattern consistent with a higher risk of clinical progression based on knee adduction moment (KAM) magnitude and dynamic knee flexion moment (KFM) unloading features compared to OA participants with no increase in pain and asymptomatic controls (ASYM).