Cervical focal myositis in a child.

Focal myositis is a self limited, benign, inflammatory pseudotumor of skeletal muscle, which spontaneously regresses. A 10-year-old girl presenting with localized swelling of the left sternocleidomastoid muscle was seen with subsequent biopsy proven focal myositis. This is the second report of this distinct disease presenting in the neck and the first in the pediatric age group. Biopsy is the only diagnostic and therapeutic modality necessary.