Basic Pelvic Parameters Associated with Lumbar Degenerative Disease: Review Article

ABSTRACT

STUDY DESIGN: Literature review. OBJECTIVES: The aim of this study was to present updated information on the basic pelvic parameters associated with lumbar degenerative disease. SUMMARY OF LITERATURE REVIEW Sagittal imbalance has been known to be related to a poor prognosis in almost all adult spine problems, including lumbar degenerative disease. MATERIALS AND METHODS: Review of the relevant literature. RESULTS: Pelvic incidence is a morphologic parameter of the pelvis. It influences lumbar lordosis and thoracic kyphosis, and determines the limitations of pelvic retroversion in sagittal imbalance. Pelvic tilt is a positional parameter of the pelvis, indicating the degree of compensation for sagittal imbalance. A C7-sagittal vertical axis >5 cm, pelvic tilt >20°, and pelvic incidence-lumbar lordosis mismatch are known to be independent factors predictive of poor outcomes. CONCLUSIONS: The C7-sagittal vertical axis, pelvic tilt, and pelvic incidence-lumbar lordosis mismatch should be considered when surgery is planned for a patient with degenerative lumbar disease.