Assessment of spinal kinematics using open interventional magnetic resonance imaging

Assessment of spinal intersegmental motion has been a focus for research an d has depended on radiographic techniques. Radiographic techniques are limi ted because of ionizing radiation exposure, magnification errors, and image quality. Interventional magnetic resonance scanners, however, allow dynami c imaging in the scanner in different positions. Twelve healthy subjects we re scanned using a General Electric Signa SP10 open interventional magnetic resonance scanner. Subjects were scanned while they were in the supine pos ition and during sitting in flexed and extended positions. Measurements of lumbar curvature and intersegmental motion were made from the sagittal imag es obtained. The results showed that it was possible to obtain repeatable m easures of intersegmental rotation and translation from open magnetic reson ance images of the spine in flexed and extended positions. These measures o f motion are in agreement with previous data and suggest that the greatest motion occurs at the L4-L5 level. The use of interventional magnetic resona nce imaging for assessing lumbar intersegmental mobility seems promising.