In this investigation of congenital muscular torticollis, 311 infants treated consecutively for congenital torticollis over an 8-year period (1995-2003) at the Pediatric Neurology Clinic of Istanbul Medical Faculty, Istanbul University, Turkey were reviewed retrospectively. The clinical presentation, associated abnormalities, treatment, and outcomes of the overall group and of subgroups divided according to an ultrasonography-based classification were evaluated. All patients were evaluated using a standard approach: cervical ultrasonography was performed, and the patients were divided into two subgroups. Each group was scanned for other anomalies, and outcomes were compared. The mean age at diagnosis was 2.3 months; patients included in this study were 138 males and 173 females. Two clinical subgroups, comprised of sternomastoid tumors 85% and postural torticollis 15%, were identified. Passive range of motion was the initial treatment recommended for all of the patients. Follow-up data were available for all 311 patients; 95% experienced total resolution and 5% experienced subtotal resolution. We conclude that the majority of children with congenital muscular torticollis experience total resolution of symptoms. The success rate of conservative treatment is primarily dependent on the patients' age at the initiation of exercises and ultrasonographic findings. (c) 2006 by Elsevier Inc. All rights reserved.