Introduction: Benefits of surgical care for adulf spinal deformity has been shown but few guidelines exist to direct patient care. The Classification of adult spinal deformity (“Classification”) provides a clinical framework but validation of treatment algorithms have not been reported. This study aims to evaluate outcomes following surgery for adult thoracolumbar/lumbar spinal deformity based upon a consensus algorithm developed by the Spinal Deformity Study Group.
Methods: Multi‐center analysis of consecutive adult patients classified as Type IV, V curves (thoracolumbar,lumbar major) with sagittal malalignment (modifiers B/C, P/VP) were selected: 274 patients, 144 with lyr, 69 with 2yr follow up (radiographs, health related quality of life (HRQOL) data and operative details). The treatment algorithm calls for fusion to the sacrum and osteotomies for these cases. Statistical comparison of outcomes was made between groups dependant upon adherence with the algorithm.
Results: Of 274 patients, 192 (70.1%) had fusions that extended to SI, 130 patients (47.4%), had osteotomies. By SRS measures (total, appearance, mental), patients treated according to the algorithm had greater improvement than those whose fusions stopped short of the sacrum (p,0.05). In terms of SRS Appearance MCID at One Year ‐ 75% of fusions at the guideline level met the threshold, compared to 43% of those with fusions higher than the guideline (p = .001, chi square test). By osteotomy guidelines, greater improvement was found for those having osteotomies: one‐year and two year SRS Appearance (p = .01), SRS Mental (p= .003) and SRS Total Score (p=.005).
Conclusion: A Classification of adult deformity has been established and efforts are directed at validating an algorithm for optimal surgical approach. In this study combining Classification and treatment algorithm lead to improved outcome following surgery. The need for osteotomies and extension to the sacrum for Type IV/V sagittally imbalanced patients is established.
Significance: The Classification of adult spinal deformity can be combined with a treatment algorithm. In the setting of thoracolumbar/lumbar major curves with sagittal plane malalignment the algorithm effectively guides ideal treatment for best outcome based upon HRQOL measures.