Perioperative Repetitive Transcranial Magnetic Stimulation Reduces Postoperative Cognitive Dysfunction and Inflammation in Elderly Patients Undergoing Total Knee Arthroplasty: A Randomized Controlled Trial.

Abstract

Postoperative cognitive dysfunction (POCD) is a major complication in elderly patients undergoing total knee arthroplasty (TKA), often linked to neuroinflammation. Repetitive transcranial magnetic stimulation (rTMS) has shown potential in modulating neural activity and reducing inflammation, but its perioperative efficacy in preventing POCD remains underexplored. This study aimed to evaluate the effectiveness of perioperative rTMS in reducing POCD and inflammation in elderly patients undergoing TKA. In this single-center, randomized, double-blind trial, 60 elderly patients (≥ 60 years) scheduled for primary, elective TKA were randomly assigned to either an Active-rTMS or Sham-rTMS group. The Active-rTMS group received 10 Hz stimulation targeting the dorsolateral prefrontal cortex for five consecutive days perioperatively, while the Sham-rTMS group underwent identical procedures with the coil positioned perpendicularly to the skull to ensure no active stimulation. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA), and serum inflammatory biomarkers, including interleukin 1 beta (IL-1β), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), and high mobility group box 1 (HMGB1), were measured on preoperative days six and one and postoperative days three (POD three) and seven (POD seven). The Active-rTMS group demonstrated significantly higher MoCA scores at postoperative days three and seven (POD three: 25.3 ± 1.4 versus 23.7 ± 2.1, P = 0.001; POD seven: 26.1 ± 1.2 versus 24.4 ± 1.7, P < 0.001) and a lower cumulative POCD incidence (two versus 10 cases, P = 0.01). Postoperative levels of IL-1β, IL-6, TNF-α, and HMGB1 were significantly reduced in the Active-rTMS group (P ≤ 0.002), indicating attenuated neuroinflammation. Perioperative rTMS significantly reduces POCD incidence and inflammation in elderly patients undergoing TKA, supporting its potential as a non-invasive strategy to preserve cognitive function. The study was registered with the Chinese Clinical Trial Registry (registration number: ).