EEG-Based Cortical Alterations in Patients Following Total Hip and Knee Arthroplasty Due to Osteoarthritis: Pre- and Post-Operative Assessment.

Quantitative electroencephalography (qEEG) has not yet been systematically applied to characterize cortical bioelectrical activity in patients undergoing total hip or knee arthroplasty. The aim of this study was to evaluate pre‑ to post‑operative changes in cortical activity and their relationship with functional outcomes after arthroplasty. Neuroplastic changes were examined in 81 patients with end‑stage osteoarthritis (33 hip, 48 knee) scheduled for primary total joint arthroplasty. All participants underwent clinical assessment one week before surgery and three months postoperatively using the Harris hip score (HHS), knee society score (KSS), and oxford knee score (OKS), together with full‑cap EEG recordings (19 electrodes) during resting state and stair‑climbing motor imagery. EEG analysis revealed a generalized increase in low alpha band power during rest after arthroplasty in both hip (n = 33) and knee (n = 48) patients, particularly over frontocentral and parietal regions (mean increases ∼1-3 µV2; p < 0.001; Cohen's d up to 1.6). High alpha band changes were less consistent and often moved in the opposite direction over posterior sites, especially after knee arthroplasty and during motor imagery (p < 0.001). Theta power also increased post‑surgery, most prominently over frontal and central electrodes during both rest and motor imagery (p < 0.001). Only a few moderate correlations between changes in alpha band power and improvements in joint-specific clinical scores reached significance (Spearman's ρ, p < 0.05). These findings indicate that functional recovery after total hip and knee replacement is accompanied by measurable, band‑specific reorganization of cortical oscillatory activity, with partially distinct patterns between joints. The results support a relevant contribution of central mechanisms to postoperative outcomes and highlight qEEG as a promising tool for monitoring neuroplastic adaptation following major joint arthroplasty.This study reveals significant neuroplastic changes in cortical EEG activity post total hip/knee arthroplasty in osteoarthritis patients, with increased low alpha and theta power over frontocentral/parietal regions during rest and motor imagery. These alterations accompany functional improvements (HHS/KSS), suggesting qEEG's potential for monitoring recovery.