Bilateral sternocleidomastoid pseudotumors—a case report and literature review

Sternocleidomastoid (SCM) pseudotumors, also known as fibromatosis colli or congenital torticollis, are painless benign neck lumps found in newborns. Whilst unilateral cases are relatively common, bilateral SCM pseudotumors are a rare phenomenon with only a handful of cases reported internationally. We present the case of a 5-week-old infant who was brought to the emergency department with painless, bilateral, palpable anterior neck masses following a slightly traumatic but otherwise uncomplicated spontaneous delivery. An ultrasound scan of his neck revealed well-defined soft tissue lesions within both of the SCM muscles. He was subsequently diagnosed with bilateral SCM pseudotumors. This case emphasizes the importance of considering this entity as a differential diagnosis in infants presenting with bilateral palpable neck masses.