Staircase Nutritional Intervention for Elderly Patients Undergoing Spinal Fusion Surgery

The goal of this prospective multicenter randomized controlled clinical trial is to evaluate the efficacy of a staircase nutritional intervention in reducing postoperative complications and improving long-term functional recovery in elderly patients aged ≥75 years scheduled for spinal fusion surgery. The main questions it aims to answer are: 1. Does the staircase nutritional intervention reduce the 30-day postoperative complication rate, as measured by the Comprehensive Complication Index (CCI), compared to conventional ERAS diet management? 2. Does the staircase nutritional intervention improve 1-year functional recovery, as assessed by Oswestry/Neck Disability Index (ODI/NDI) and health-related quality of life (EQ-5D), compared to conventional ERAS diet management? Researchers will compare the intervention group receiving MNA - based staircase nutritional intervention (including 14-day preadmission oral nutritional supplementation, perioperative personalized nutritional support, and postdischarge continuous management) combined with surgery-specific prehabilitation training to the control group receiving conventional ERAS diet management to see if the former leads to better clinical outcomes and long-term functional recovery. Participants will Undergo randomization: Be randomly assigned to either the intervention group or the control group. Receive assigned interventions: Control group: Receive conventional ERAS diet management, including preadmission nutritional education and early postoperative oral intake. Intervention group: Undergo MNA - based staircase nutritional intervention and surgery-specific prehabilitation training. Participate in follow-up: Complete short-term (within 90 days postoperatively) and long-term (6 and 12 months postoperatively) follow-up assessments, including laboratory tests, functional evaluations, and satisfaction surveys.