Sagittal spinal misalignment (SSM) is an established cause of pain and disability. Treating physicians must be familiar with the radiographic findings consistent with SSM. Additionally, the restoration or maintenance of physiological sagittal spinal alignment after reconstructive spinal procedures is imperative to achieve good clinical outcomes. The C-7 plumb line (sagittal vertical axis) has traditionally been used to evaluate sagittal spinal alignment; however, recent data indicate that the measurement of spinopelvic parameters provides a more comprehensive assessment of sagittal spinal alignment. In this review the authors describe the proper analysis of spinopelvic alignment for surgical planning. Online videos supplement the text to better illustrate the key concepts.
Abbreviations used in this paper:CA = coronal alignment; CSVL = central sacral vertical line; HRQOL = health-related quality of life; LL = lumbar lordosis; PI = pelvic incidence; PSO = pedicle subtraction osteotomy; PT = pelvic tilt; SA = sagittal alignment; SPI = spinopelvic inclination; SS = sacral slope; SSM = sagittal spinal misalignment; SVA = sagittal vertical axis; TK = thoracic kyphosis; TLK = thoracolumbar kyphosis.
Address correspondence to: Christopher P. Ames, M.D., Department of Neurosurgery, University of California, Medical Center, 400 Parnassus Avenue, A850, San Francisco, California 94143. email: firstname.lastname@example.org.
Please include this information when citing this paper: published online March 23, 2012; DOI: 10.3171/2012.2.SPINE11320.
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