Background <p>Scheuermann kyphosis (SK) is a spinal deformity characterized by exaggerated kyphosis, frequently requiring surgical correction. Selection of the lowest instrumented vertebra (LIV) is critical in optimizing outcomes, with options including the stable sagittal vertebra (SSV) and first lordotic vertebra (FLV). This systematic review evaluates the clinico-radiological outcomes and complications associated with SSV and FLV as LIVs.</p> Methods <p>A systematic review were conducted following PRISMA guidelines. Seven studies comprising 311 patients (142 in the SSV group and 169 in the FLV group) were included. Outcomes analyzed included pre- and postoperative radiographic parameters (kyphosis, lumbar lordosis, sagittal balance), correction rates, incidence of distal junctional kyphosis (DJK), and revision surgery for DJK. Statistical analysis used Review Manager 5.4 with heterogeneity assessed using I² and Q tests. Evidence quality was evaluated using the GRADE framework.</p> Results <p>Pre- and postoperative kyphosis was significantly higher in the SSV group, while lumbar lordosis and sagittal balance were comparable. Although the correction rates were similar between groups, the incidence of DJK was significantly higher in the FLV group (OR 0.20, <i>p</i> = 0.04). Sensitivity analysis revealed that after removing the most heterogeneous study, the difference in DJK incidence was no longer statistically significant. Revision surgeries for DJK remained significantly higher in the FLV group (OR 0.26, <i>p</i> = 0.01).</p> Conclusion <p>Fusion to SSV may reduce the incidence of DJK and revision surgery compared to FLV, with comparable radiological outcomes. However, these findings were sensitive to study heterogeneity, and the significance of DJK difference disappeared after sensitivity analysis, highlighting the need for further prospective studies with larger sample sizes to strengthen the evidence.</p>