The radiographic parameters for the prediction of spondylolysis and spondylolisthesis

The grading of severity of spondylolisthesis and measurement of percentage slip are well-known radiological parameters that affect progression of the slip. The role of pelvic morphology and spino-pelvic balance in the prediction of spondylolisthesis has been recently scrutinized. Pelvic incidence, sacral slope, and pelvic tilt define the pelvic morphology and position. Pelvic incidence is most important as it determines the spino-pelvic balance, affects the biomechanical stresses at the lumbosacral junction, and predicts the progression of spondylolisthesis. A new classification by the Spinal Deformity Study Group incorporates pelvic morphological parameters and global sagittal balance and seeks to guide surgical management of spondylolisthesis.