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

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.