Radiographical Spinopelvic Parameters and Disability in the Setting of Adult Spinal Deformity

STUDY DESIGN: Prospective multicenter study evaluating operative (OP) versus nonoperative (NONOP) treatment for adult spinal deformity (ASD). OBJECTIVE: Evaluate correlations between spinopelvic parameters and health-related quality of life (HRQOL) scores in patients with ASD. SUMMARY OF BACKGROUND DATA: Sagittal spinal deformity is commonly defined by an increased sagittal vertical axis (SVA); however, SVA alone may underestimate the severity of the deformity. Spinopelvic parameters provide a more complete assessment of the sagittal plane but only limited data are available that correlate spinopelvic parameters with disability. METHODS.: Baseline demographic, radiographical, and HRQOL data were obtained for all patients enrolled in a multicenter consecutive database. Inclusion criteria were: age more than 18 years and radiographical diagnosis of ASD. Radiographical evaluation was conducted on the frontal and lateral planes and HRQOL questionnaires (Oswestry Disability Index ODI, Scoliosis Research Society-22r and Short Form SF-12) were completed. Radiographical parameters demonstrating highest correlation with HRQOL values were evaluated to determine thresholds predictive of ODI more than 40. RESULTS: Four hundred ninety-two consecutive patients with ASD (mean age, 51.9 yr) were enrolled. Patients from the OP group (n = 178) were older (55 vs. 50.1 yr, P 40) included: PT 22° or more, SVA 47 mm or more, and PI - LL 11° or more.