Clinical Significance of Prognostic Nutritional Index in Patients Who Underwent Palliative Surgery for Spine Metastasis

<b>Background/Objectives</b>: Malnutrition is common in patients with metastatic spine tumors (MSTs) and may adversely affect surgical outcomes. The Prognostic Nutritional Index (PNI) reflects both nutritional and immune status, but its role in palliative MST surgery is not well defined. The aim of this study was to investigate the association between preoperative the PNI and postoperative outcomes, including functional recovery and survival, in patients undergoing palliative surgery for MSTs. <b>Methods</b>: A brief description of the main methods or treatments applied. This can include any relevant preregistration or specimen information. <b>Results</b>: Patients with a higher PNI (≥42.8) demonstrated significantly better postoperative ambulation and longer overall survival compared to those with a lower PNI (<42.8). The higher PNI group showed earlier ambulation (<i>p</i> = 0.017) and longer median survival (30.7 vs. 7.0 months; <i>p</i> = 0.002). Multivariate analysis confirmed that a PNI ≥ 42.8 was an independent predictor of early ambulation (HR = 1.516; 95% CI: 1.010-2.277; <i>p</i> = 0.045) and prolonged survival (HR = 0.955; 95% CI: 0.927-0.985; <i>p</i> = 0.003). No significant association was found between the PNI and postoperative infections. <b>Conclusions</b>: The PNI is a simple and effective predictor of postoperative functional recovery and survival in patients undergoing palliative surgery for MSTs. Its routine preoperative assessment may help stratify surgical risk, guide nutritional interventions, and optimize clinical outcomes in this vulnerable population.