The Effect of Smith-Peterson Osteotomy on Blood Loss during Surgical Correction of Adolescent Idiopathic Scoliosis.

INTRODUCTION Surgical correction of adolescent idiopathic scoliosis is inevitably accompanied by blood loss. About 37-85% of patients undergo allogeneic transfusions associated with a risk of serious complications. Prediction of the expected blood loss volume remains a topical problem. In this regard, there is a need to clarify predictors of increased blood loss. AIM To assess the effect of vertebrectomy on the intraoperative blood loss volume during surgical correction of adolescent idiopathic scoliosis. MATERIALS AND METHODS A retrospective study included 511 adolescents who underwent posterior correction of spinal deformity. Two groups were allocated: Group I consisted of 303 patients who underwent multilevel transpedicular fixation; Group II included 208 patients who underwent multilevel transpedicular fixation combined with Smith-Peterson osteotomy. RESULTS Intergroup comparisons revealed significant differences in the number of transpedicular fixation levels and the volume of blood loss, which were higher in Group II. After aligning the groups by the number of transpedicular fixation levels using the Propensity Score Matching method, no statistically significant difference was observed. We derived formulas for calculating the expected blood loss volume in Groups I and II. Comparison of the formulas revealed that the formula for Group II predicted a significantly lower volume of blood loss, by 2.51%, while the formula for Group I predicted a significantly higher volume of blood loss, by 3.27%. In our opinion, application of the formula that overestimates expected intraoperative blood loss is most reasonable due to a possibility of the worst case scenario during surgery; therefore, the formula for Group I approaches a universal model for use. CONCLUSION Smith-Peterson osteotomy did not affect the amount of blood loss during surgical correction of adolescent idiopathic scoliosis, considering the number of transpedicular fixation levels.