Sagittal Plane Alignment of the Spine and Gravity

Legaye J. Sagittal Plane Alignment of the Spine and Gravity: A Radiological and Clinical Evaluation. Acta Orthopaedica Belgica April 2005; 71(2):213-220.

In this study, standing full-spine lateral x-rays were taken to measure sacral slope and the pelvic angles compared to the curves and vertebral positions throughout the spine on the lateral or sagittal view.

“Analysis of the sagittal balance of the spine includes the study of the spinal curves and of the pelvis on the sagittal plane. It therefore requires full-spine lateral radiographs.”

Dimar JR, Carreon LY, Lebelle H, et al. Intra- and Inter-Observer Reliability of Determining Radiographic Sagittal Parameters of the Spine and Pelvis Using a Manual and a Computer-Assisted Methods. European Spine Journal October 2008; 17 (10):1373-1379.

This study used 30 cm x 90 cm (14” by 36”) lateral films and digital measurements. They did find digital, computer-assisted measuring systems to be more reliable than manual methods, the latter done by spinal surgeons.

“This [global spino-pelvic view] highlights the need for a consistent method of sagittal plane radiographic measurement other than the traditional manual method and the critical need for full length 90 cm radiographs for all sagittal plane deformities. Regardless of whether or not the pathology is a fracture, infection, structural kyphosis or a high grade spondylolisthesis, the restoration of reasonable sagittal balance is paramount to long term surgical [study was for and done by surgeons] success and patient satisfaction.

“The importance of maintaining proper spino-pelvic alignment cannot be over stated.”

“The importance of maintaining appropriate sagittal spino-pelvic balance can best be demonstrated from the adult deformity patient’s perspective. Patients with significant sagittal imbalance had poor two-year healthrelated quality of life measures.”

“… clearly established the need for 90 cm radiographs (including the hips)…”