[How to restore the proper lumbar lordosis in spine surgery].

Sagittal alignment of the spine significantly affects the physical function. In this article, we review the clinical application of several spinal-pelvic parameters, analyze the impact factors of sagittal alignment and provide calculating methods to value the correcting degrees. Spine surgeons should get a deep understanding of the spinal-pelvic parameters, differentiate the functional and structural imbalance. Every patient needs thorough preoperative evaluation to restore the proper alignment during surgery and avoid overcorrection.