Intraoperative Cell Salvage in Spine Surgery: A Meta-Analysis of Reduced Allogeneic Transfusion with Implications for Orthopedic and Sports Practice.

Background: Spine surgery, particularly multilevel fusion and deformity correction, is associated with substantial intraoperative blood loss. The effectiveness of intraoperative cell salvage in reducing allogeneic transfusion in this setting remains uncertain. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA 2020 guidelines. PubMed/MEDLINE, Scopus, and Web of Science were searched from inception to March 2026. Randomized and non-randomized comparative studies evaluating intraoperative cell salvage in spine surgery were included. Primary outcomes were allogeneic transfusion rate and number of transfused units. Random-effects models were used to pool risk ratios (RR) and mean differences (MD). Results: Four comparative studies involving 360 patients were included, of which two contributed to the meta-analysis of transfusion rate and three to transfused units. Intraoperative cell salvage was significantly associated with a reduced risk of allogeneic transfusion (RR, 0.51; 95% CI, 0.35-0.76; I² = 0%), with a consistent direction of effect across studies. A modest reduction in transfused units was also observed (MD, -0.40 units; 95% CI, -0.66 to -0.14; I² = 41%). Secondary outcomes were heterogeneous and did not demonstrate consistent effects across studies. Conclusion: Intraoperative cell salvage may reduce exposure to allogeneic transfusion in spine surgery, with a more limited effect on transfusion volume. Its clinical benefit appears most relevant in procedures with high expected blood loss. However, the strength of the evidence is constrained by the small number of comparative studies, limited statistical power, and inclusion of non-randomized designs. Further adequately powered randomized trials are required to better define its role.