Hybrid Anterior Column Realignment - Pedicle Subtraction Osteotomy for Severe Rigid Sagittal Deformity.

Abstract

OBJECTIVE\nRecently, a hybrid anterior column realignment-pedicle subtraction osteotomy (ACR-PSO) approach has been conceived for patients with severe rigid sagittal deformity, the clinical and radiographic outcomes of which require further investigation compared to ACR only.\n\n\nMETHODS\nA single-center, retrospective chart review identified patients undergoing a combination of hyperlordotic lateral lumbar interbody grafting (ACR) and concurrent Schwab grade 3 three-column osteotomy and propensity-matched patients undergoing ACR only in the same timeframe. Anterior longitudinal ligament was directly released or partially sectioned in all patients. Chart data included demographics, Oswestry Disability Index (ODI) scores, ACR and osteotomy locations, cage dimensions, fusion length, and complications. Radiographic measurements included lumbar lordosis, sagittal vertical axis (SVA), pelvic tilt (PT), and proximal junctional kyphosis (PJK).\n\n\nRESULTS\n14 patients were enrolled in the ACR+PSO group and 36 in the ACR-only group. Mean ages were 68.5 and 63.9 years, 64% and 67% female, average BMI was 27.9 and 29.2, and cardiopulmonary comorbidities were 21% and 17%, respectively. There was no difference in complications (p = 0.347). The average follow-up for the ACR+PSO and ACR-only groups were 22 and 18 months, respectively. Excluding two mortalities, fusion occurred in all patients. Average change in lumbar lordosis measured -40.8 ± 9.2° and -19.1 ± 15.7° (p = 0.0006) and PT correction measured 10.5 ± 3.4° and 27.3 ± 1.6° (p < 0.0001), respectively.\n\n\nCONCLUSION\nFor patients with severe rigid sagittal deformity, the hybrid ACR-PSO approach offers significant restoration of lumbar lordosis compared to ACR only, with similar complications but reduced PT correction.