Neurophysiological Markers of Adaptation and Compensation Following Lower Limb Amputation: An Analysis of EEG Oscillations and Clinical Predictors from the DEFINE Cohort Study.

Abstract

Background: Neuroplasticity, involving cortical and subcortical reorganization, plays a critical role in the adaptation and compensation process post-amputation. However, underlying neurophysiological changes remain unclear, particularly in brain oscillations. Methods: This is a cross-sectional analysis that includes baseline data from 48 individuals with lower limb amputation from our DEFINE Cohort Study project. EEG data were collected using a 64-channel system during a 5-min resting-state period. Preprocessed data were analyzed for delta and alpha oscillations across frontal, central, and parietal regions. Logistic regression models examined associations between EEG oscillations and clinical variables, including cognition (MoCA), functional independence (FIM), and phantom limb sensations (PLS). Results: The multivariate logistic regression analysis revealed distinct patterns of association between EEG oscillations and clinical variables. Delta oscillations were inversely associated with cognitive scores (OR: 0.69; p = 0.048), while higher delta power was related to the absence of PLS (OR: 58.55; p < 0.01). Frontal alpha power was positively linked to cognitive function (OR: 1.55; p = 0.02) but negatively associated with functional independence (OR: 0.75; p = 0.04). Conclusions: These findings suggest that lower frequencies, such as delta oscillations, play a role as potential compensatory brain rhythms. In contrast, alpha oscillations may reflect a more adapted pattern of brain reorganization after amputation.