Brain activity related to kinesiophobia before and after total hip arthroplasty in patients with hip osteoarthritis: a pilot task-related functional MRI study.

Kinesiophobia that persists in some patients after total hip arthroplasty (THA) is a significant factor hindering functional recovery. Its neural basis is not well understood. This exploratory prospective cohort study aimed to investigate changes in kinesiophobia-related brain activity before and after THA in patients with hip osteoarthritis (HOA) using task-related functional MRI (fMRI) during a motor task. Six women (70.8 ± 13.1 years) who underwent THA for left HOA were assessed before and 2 weeks after surgery. Brain activity was measured using block-design fMRI during an active left hip flexion motor task. Clinical assessments included the Tampa Scale for Kinesiophobia short version (TSK-11), Visual Analog Scales (VAS) for kinesiophobia and pain, and gluteus medius muscle activity (% maximum voluntary contraction, %MVC) during the gait stance phase. Brain image analysis was performed using the General Linear Model in MATLAB R2024b and SPM25, with activation regions identified using Montreal Neurological Institute coordinates. fMRI analysis revealed activity in the anterior cingulate cortex (ACC) and middle cingulate cortex (MCC), both pre- and postoperatively. Postoperatively, TSK-11, kinesiophobia VAS, and pain VAS scores significantly decreased (P < 0.05), while %MVC increased (P < 0.01). Changes in ACC activity showed a positive correlation with changes in TSK-11 and kinesiophobia VAS. Changes in MCC activity showed a negative correlation with changes in pain VAS and %MVC. These findings suggest that postoperative psychological improvements are associated with neuroplastic changes in the cingulate gyrus, which are associated with functional recovery. This suggests a potential neural mechanism involved in the recovery from kinesiophobia.