Do Quantitative Resting-State EEG Changes Occur in Patients with Knee Osteoarthritis Undergoing Rehabilitation?

Knee osteoarthritis (KOA) is a chronic condition strongly associated with pain, in which central sensitization plays a key role. Yet, its neurobiological mechanisms remain poorly understood. Quantitative resting-state EEG offers a non-invasive approach to investigate these processes. This longitudinal study examined EEG changes before and after rehabilitation in patients with chronic KOA. Resting-state EEG and WOMAC pain and function scores were assessed pre- and post-rehabilitation. Relative power in delta, theta, alpha, and beta bands was analyzed across frontal, central, and parieto-occipital regions. Subgroup analyses explored the influence of baseline characteristics and clinical response. Fifty-nine patients (median age 67.6 years; pain duration 3 months–41 years) completed the study, with 80.7% showing clinical improvement. Although no statistically significant EEG changes were observed, trends suggested increased beta and decreased alpha power following rehabilitation. Subgroup analyses revealed higher left frontal beta power in patients without pain relief, while those with pain lasting ≥10 years showed reduced right frontal beta power. This first real-world investigation indicates that EEG may capture maladaptive or compensatory mechanisms in KOA and holds promise as a biomarker, warranting confirmation in future research.