1000 Section - The Impact of Preoperative Nutritional Support on Outcomes for Patients Undergoing Spinal Surgery: A Systematic Review

Objectives : Preoperative malnutrition is associated with significantly increased postoperative infections and length of stay following spinal surgery. However, evidence supporting nutritional optimization comes predominantly from non-spinal surgeries. This review fills a critical gap, investigating the effects of specific nutritional therapies on outcomes for spinal surgery patients.

Design: PubMed, Web of Science, Scopus, and Cochrane were searched. Criteria for inclusion were primary articles evaluating patients who underwent elective spinal surgeries and received preoperative nutritional support. ERAS protocol-based studies were multivariable and thus excluded. The primary outcome was postoperative pain, measured by the visual analog scale (VAS) 1-10. For each nutritional intervention, a subgroup meta-analysis generated pooled estimates for VAS-pain. Secondary outcomes (length of stay, disability, and stability) were narratively synthesized due to heterogeneity. This study was reported following PRISMA guidelines. PROSPERO-registered (ID: 1027295).

Results: From 6347 records, 8 eligible studies satisfied the inclusion criteria. As the primary outcome, 3-month postoperative VAS-pain was reduced by 2.17 (95%CI −2.60,−1.74) with protein supplementation and by 1.3 (95%CI −1.59,−1.09) with vitamin D supplementation compared to placebo in posterior lumbar fusion studies.

Protein supplementation also improved Oswestry Disability Index scores at 1 and 3-months postoperatively compared to placebo. Carbohydrate loading showed no effect on hospital or PACU/MICU lengths of stay. Evidence for vitamin D on postoperative stability was inconsistent, as one study reported significantly greater limits of stability at 5 weeks and post-rehabilitation, while another found no difference between groups.

Conclusion: Protein and vitamin D supplementation demonstrated meaningful reductions in VAS-pain scores compared to placebo, with protein having a greater effect. Additionally, protein supplementation may improve disability outcomes. Interestingly, no evidence supported reduced hospital stay with carbohydrate loading, and evidence regarding vitamin D’s effect on postoperative stability was conflicting. Due to the limited quantity and heterogeneity of available studies, further high-quality prospective research is needed to clarify these trends.