Body Position and Anesthesia Can Alter Scoliosis Deformity
Changes in apparent curvature during surgery can complicate selection of fusion levels
WEDNESDAY, Aug. 18 (HealthDay News) -- Spine curvature in scoliosis is corrected somewhat by different body positions and anesthesia during surgery, which can confound the determination of fusion levels, according to a study in the August issue of the Journal of Spinal Disorders & Techniques.
Choon Sung Lee, M.D., of the University of Ulsan in Seoul, South Korea, and colleagues evaluated 62 structural curves (mean preoperative Cobb angle, 45.5 degrees; mean preoperative rotation angle, 18.7 degrees) in 31 patients with adolescent idiopathic scoliosis who had surgery. The researchers identified the end and neutral vertebrae and evaluated postoperative Cobb angle and rotational deformity corrections in standing, supine, side bending, postanesthesia, and postoperative radiographs.
The investigators found that Cobb angles with supine position, anesthesia, side-bending, and surgery decreased with correction rates of 25.0, 31.7, 59.5, and 74.0 percent, respectively, while rotational deformities decreased with the correction rates of 6.1, 24.5, 6.2, and 25.7 percent respectively. End vertebrae changed in 58.1 percent of patients in supine and postanesthesia radiographs, and the neutral vertebrae changed in 32.3 percent of patients in supine radiographs and in 64.5 percent in postanesthesia radiographs, complicating the selection of fusion levels.
"In summary, Cobb angle in preoperative standing radiograph was significantly corrected by supine position, anesthesia, side bending, and surgical intervention. Of these results, the effects of supine position and anesthesia were similar. Rotation angle, however, did not show such a great change, and only anesthesia and surgical correction significantly decreased it," the authors write.