Preoperative Nutritional Optimization in Lumbar Spine Surgery: Associations, Interventions, and Clinical Implications

Malnutrition is an independent risk factor for postoperative complications following lumbar spine surgery, particularly surgical site infection and wound-related adverse events. As perioperative care has shifted toward proactive risk modification, nutritional optimization has gained attention alongside established targets such as anemia correction, glycemic control, and smoking cessation. While associations between poor nutritional status and adverse outcomes are well established, the degree to which targeted nutritional interventions reduce postoperative risk in lumbar spine surgery remains less clearly defined. This review synthesizes current evidence on malnutrition assessment in lumbar spine populations, biological mechanisms linking nutritional deficits to complications, and the effectiveness of perioperative nutritional optimization strategies. Common markers such as serum albumin and composite indices including the Prognostic Nutritional Index are consistently associated with early postoperative morbidity but are influenced by inflammation and comorbidity burden. Sarcopenia represents a distinct yet overlapping phenotype associated with reduced physiologic reserve and impaired recovery. Emerging interventional evidence, including a randomized trial and a pooled analysis, suggests that perioperative nutritional supplementation, particularly high-protein oral supplementation, can reduce overall and wound-related complications, with the greatest benefit observed among patients with demonstrable baseline nutritional risk. The literature is limited by heterogeneity in malnutrition definitions, intervention timing, and outcome reporting, as well as underrepresentation of severely malnourished patients. Overall, current evidence supports routine nutritional risk screening and targeted supplementation as a low-risk, scalable component of perioperative optimization in lumbar spine surgery. Future research should focus on standardized nutritional phenotyping and adequately powered, spine-specific prospective trials to refine patient selection and intervention strategies.