ARTICLE: PDF OnlyDerotational Analysis of Cotrel-Dubousset Instrumentation in Idiopathic ScoliosisGRAY, JOHN M. MD; SMITH, BRIANT W. MD; ASHLEY, R. KIRKLIN MD; LaGRONE, MICHAEL O. MD; MALL, JAY MDAuthor Information Shriners Hospital for Crippled Children, Children's Hospital, San Francisco, California, and the Department of Orthopaedic Surgery, University of California, San Francisco, California. Spine: August 1991 - Volume 16 - Issue 8 - p S394 Free Abstract Ten patients with idiopathic scoliosis were treated with posterior spinal fusion and Cotrel-Dubousset instrumentation. Computed tomographic scans and intraoperative photographs were used to evaluate the derotational effect of the Cotrel-Dubousset instrumentation. The frontal deformity was corrected from an average of 51 ± to 15± and the kyphosis from 9.5° to 18°. The amount of preoperative vertebral rotation was variable, however, and insignificant postoperative changes were documented in the majority of cases. © Lippincott-Raven Publishers.