Sagittal Spinal Alignment in Adult Spinal Deformity
* Changes in spinal alignment trigger several compensatory changes in the pelvis and lower extremities to maintain upright posture. Activating these mechanisms of compensation may require increased energy expenditure to maintain upright posture. * The Scoliosis Research Society-Schwab Adult Spinal Deformity (ASD) classification system allows for a uniform classification and discussion of ASD. A higher sagittal deformity classifier is associated with increased disability. * Age-related changes in spinal alignment are important to consider when setting alignment goals for deformity correction. Less-aggressive correction should be considered in older patients because of their increased risk for complications. * A structured approach to the treatment of ASD consists of 6 steps: (1) find and quantify the driver of deformity, (2) evaluate how deformity impacts global alignment, (3) define alignment targets, (4) determine spinal flexibility, (5) choose a surgical strategy, and (6) execute this strategy intraoperatively in a controlled fashion.