There were 47 patients with congenital muscular torticollis who underwent operative release. After a mean follow-up of 74 months (60 to 90), they were divided into two groups, one aged one to four years (group 1) and the other aged five to 16 years (group 2). The outcomes were assessed by evaluating the following parameters: deficits of lateral flexion and rotation, craniofacial asymmetry, surgical scarring, residual contracture, subjective evaluation and degree of head tilt. The craniofacial asymmetry, residual contracture, subjective evaluation and overall scores were similar in both groups. However, group 2 showed superior results to group 1 in terms of the deficits of movement, surgical scarring and degree of head tilt. It is recommended that operative treatment for congenital muscular torticollis is postponed until the patient can comply successfully with post-operative bracing and an exercise programme.