Patients and methods: The files of 12 children presenting with a sternocleidomastoid tumor of infancy at the Timone Children's Hospital in Marseille between 1990 and 1999 were retrospectively studied. All of them underwent physical and ultrasonographic examination.
Results: The mass was firm, within the lower two-thirds of the sternocleidomastoid muscle. Ultrasonographic examination showed a soft tissue mass independent of the great vessels. Biopsy revealed a benign fibrous lesion. Eleven children were treated with stretching exercises and a surgical therapy was performed for one in whom physical therapy was unsuccessful.
Conclusion: The sternocleidomastoid tumor of infancy is a lateral neck mass affecting children between the ages of two and four weeks. Most of the time it spontaneously resolves in four to eight months. It may be associated with congenital muscular torticollis and requires physical therapy. Surgery should be reserved for children who have failed with this treatment.