INTRAOPERATIVE EVALUATION OF SPINAL CORONAL ALIGNMENT VIA T-SQUARE SHAPED TOOL IN THORACOLUMBAR INSTRUMENTATION

Objective: Postoperative coronal malalignment (CM) is associated with suboptimal surgical outcomes and a diminished quality of life in spinal deformity patients.Several risk factors for postoperative CM are proposed, including type 2 CM, pelvic obliquity, and lumbosacral fractional curve.Intraoperative assessment of coronal alignment plays a pivotal role in avoiding postoperative CM.A T-square-shaped tool (T-tool) has been proposed as a surgical device to evaluate the coronal balance intraoperatively.In this study, we evaluate the effectiveness of the T-tool in intraoperative coronal alignment correction in patients undergoing thoracolumbar spinal instrumentation. Materials and Methods:The study includes patients who had preoperative coronal spinal deformity and/or sagittal imbalance.The T-tool was used intraoperatively in all patients.Radiological measurements were obtained using pre-and postoperative standing scoliosis X-rays.Pelvic obliquity and leg-length discrepancy were also evaluated.Preoperative and postoperative C7-coronal vertical axis (CVA) and Cobb angle of the coronal curve were measured.CM was classified according to the Obeid-CM classification.The results were compared statistically.Results: Six hundred twenty-nine patients were included in the study.Degenerative deformity was observed in 553 (87.92%) patients, while adolescent idiopathic scoliosis was observed in 76 (12.08%) patients.The preoperative and postoperative C7-CVA were 27.1611.44and 8.645.21,respectively.The mean coronal Cobb angle decreased from 24.9021.13to 14.035.68.No patient demonstrated postoperative worsening of CM. Conclusion:The T-tool is a feasible and cost-effective instrument for intraoperative assessment of the coronal spinal alignment, and it may contribute to the improvement of surgical outcomes and reduced postoperative complications.