Simultaneous prone transpsoas interbody fusion and osteotomies for severe deformity correction: multi-institutional retrospective review

Background: The increasing prevalence of adult spinal deformity (ASD) highlights the need for effective treatment strategies. While minimally invasive spine surgery has improved outcomes, patients with severe deformity often require more extensive correction. This study evaluates the outcomes of combining prone transpsoas (PTP) lumbar interbody fusion with posterior column osteotomies (PCO) or pedicle subtraction osteotomies (PSO) for severe ASD correction. Methods: This retrospective, multicenter cohort study evaluated pre- and postoperative changes in 15 patients with severe ASD [minimally invasive spinal deformity revision 2 (MISDEF2) class III/IV] treated with a hybrid approach combining PTP with simultaneous PSO or PCO. Radiographic spinopelvic parameters included pelvic incidence-lumbar lordosis (PI-LL) mismatch, sagittal vertical axis (SVA), T1 pelvic angle (TPA), segmental lordosis (SL), and coronal Cobb angle. Patient-reported outcomes included Oswestry Disability Index (ODI) and Visual Analogue Scale scores for back (VAS-B) and leg (VAS-L) pain. Differences between pre- and post-operative outcomes were assessed with paired t-tests, and Spearman’s rank coefficients were used to evaluate correlations. Results: Complication rates were similar between PCO and PSO patients. Significant improvements were observed in lumbar lordosis (LL) (P=0.002), SVA (P=0.03), TPA (P=0.04), coronal Cobb angle (P=0.03), and PI-LL mismatch (P=0.003). SL did not change significantly at any level. Clinically, ODI, VAS-B, and VAS-L scores improved significantly (P