Eight adult patients who underwent open tenotomy for idiopathic muscular torticollis were evaluated with an average follow-up of 14 years. The age of the patients at operation ranged from 20 to 37 years, with an average of 26 years. The sternal head of the sternocleidomastoid muscle was divided in two patients, both the sternal and the clavicular heads were divided in five patients, and in one patient all three heads were divided. After the operation a Minerva plaster cast was applied with the head hyperextended, bent away from the deformity, and rotated towards the deformity. Neurovascular complications were not observed. Facial asymmetry did not improve after surgery, but at follow-up all the patients had a satisfactory range of motion of the neck, although the radiographic alterations of the cervical spine present before the operation had not improved.