Combined Lateral Transpsoas Anterior Column Realignment with Pedicle Subtraction Osteotomy to Treat Severe Sagittal Plane Deformity: Cadaveric Feasibility Study and Early Clinical Experience

Abstract

Background: Traditional open approaches to correct lumbar spine deformities include 3-column osteotomies, such as a pedicle subtraction osteotomy (PSO). Minimally invasive surgical (MIS) techniques have been developed for lateral transpsoas anterior column realignment (ACR). These 2 techniques have not previously been combined. Our objective was to investigate the cadaveric feasibility of a combined hybrid MIS ACR-PSO technique for deformity correction and to review early clinical experience. Methods: The feasibility of the combined ACR-PSO technique was evaluated in 4 fresh cadaveric specimens. The operative experience, complications, and early clinical outcomes in patients treated with the combined approach to correct global sagittal imbalance were reviewed. Results: In the cadaveric study, the combined ACR-PSO resulted in a mean 46.0° increase in lordosis (P < 0.001). Nine patients treated with ACR-PSO were evaluated (mean age, 65.2 years; 33.3% female). Most patients (6/9; 66.7%) underwent ACR at L1/2 or L3/4; 8 (88.8%) had PSO at L3 or L4. On average, 10.6 ± 3.8 levels were fused. Significant decreases in mean pelvic tilt (P = 0.01), spinopelvic mismatch (P < 0.001), and T1 spinopelvic inclination (P = 0.03) were observed postoperatively; mean lumbar lordosis (P = 0.007), intradiscal angle (P = 0.001), and thoracic kyphosis (P = 0.04) significantly increased. The overall complication rate was 55.6% (5/9). Conclusions: Our early experience suggests that a combined ACR-PSO with posterior fixation allows for significant correction of segmental lordosis and global imbalance. This combined approach may maximize results attainable with hybrid MIS-open surgical techniques and represents a complementary option to PSO and other posterior approaches.