Pedicle Subtraction Osteotomy for the Treatment of Fixed Sagittal Imbalance *

This chapter includes patients severely disabled from a fixed deformity in their lumbar spines. The majority of the patients had noncompensated deformities with high sagittal vertical axis secondary to hypolordotic lumbar spines. With the patients limited to requiring pedicle subtraction osteotomy (PSO) to correct their deformities, there was no control group to compare less-invasive procedures such as Smith-Petersen osteotomy, or combined …