7 Radiographic Measurements in Spinal Deformity

Sebastien Charosky and Kathleen M. Blanke

Abstract

Radiographic measurements in spinal deformity have increased in number and technique over the years. The appreciation of the significance of various measurements has grown as well. The patient’s overall alignment, coronal and sagittal balance, and the relationship of the spine to the rest of the body need to be taken into consideration and not only the magnitude of the curve(s). The degree of curvature is measured using the Cobb method; curve progression along with other associated deformity characteristics determines the direction of treatment. The amount of radiation exposure to the patient has decreased with the development of digital X-rays, which has also resulted in clearer views of the spine for the clinician. Increasingly, radiographic measurements are accomplished digitally utilizing various measurement software.

This chapter will review the various positions for preoperative X-rays and why they are important/what information they provide for the surgeon. Much thought and consideration needs to go into the planning of the surgical procedure prior to the patient’s arrival in the operating room. The goals of any spinal deformity surgery are to safely correct and stabilize the spine, decrease pain and neurologic deficit if present, preserve as many motion segments as possible, and improve the overall quality of life and future for patients with their spine in the optimal position.

Key words

coronal - sagittal - balance - alignment - curve magnitude - Cobb angles - digital measures

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