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Fibromatosis colli

Fibromatosis colli (FMC), also termed sternocleidomastoid tumor of infancy, pseudotumor of infancy, and infancy sternocleidomastoid pseudotumor is a condition that primarily occurs in infants. It is characterized by a benign (non-cancerous) mass or lump in the sternocleidomastoid muscle, one of the major muscles in the neck. This muscle runs along the sides of the neck and helps in head and neck movement.

  • The tumor is usually on the right side, and is firm, measuring a couple centimeters in diameter.[1]
  • Many tumors go away within a year without any treatment.[1:1]
  • With stretching exercises, most will go away within six months.[1:2]
  • In a small percentage of cases the tumor persists beyond a year despite stretching.[1:3]
  • It’s the most common of the congenital muscular “torticollis” conditions, which means, “twisted neck.”[1:4]
  • SCM tumor of infancy affects boys more often than girls.[1:5]
  • Some experts have speculated that minor soft tissue abnormalities develop within the neck muscle early in gestation.[1:6]

Symptoms

  • A firm lump that appears on the side of a newborn’s neck, usually between the second and eighth weeks of life; viewed up close, it appears to be part of the neck muscle.[1:7]

  • The lump is not attached to the skin and is able to be moved when manipulated.[1:8]

  • A neck that bends slightly

  • A head that tilts

  • Facial asymmetry

  • Flat spot on the side of the head

  • Baby preferring to look in the direction away from the affected neck muscle

  • Baby that was positioned breech late in pregnancy

  • Delivery that was long and difficult

  • Testing and diagnosis

  • Your primary care provider may suspect an SCM tumor of infancy by closely looking at it and examining how it feels and responds to touch.

  • Your primary care provider will likely refer your child to a specialist known as an otolaryngologist (ear, nose and throat specialist), to confirm a diagnosis through further testing and determine the best treatment, if any is needed.[1:9]

  • The otolaryngologist will perform a physical exam of the child’s head and neck and gather a medical history.[1:10]

    • May rarely perform a rapid screening test, known as a fine-needle aspiration cytology (FNAC) to examine the cells.[1:11]
      • Your child will be sedated for this safe, minor surgical procedure. It involves inserting a hollow needle into the mass to remove cells for examination under a microscope. By examining the cells, an ENT can differentiate an SCM tumor of infancy from other conditions, including a branchial cyst, thyroglossal cyst, infantile fibromatosis, hemangioma, cystic hygroma, and cancerous lesions including neuroblastoma and lymphoma.[1:12]
    • May perform an ultrasound to locate the tumor site, determine other physical characteristics of the tumor and the extent of it, and predict how well it will go away on its own.[1:13]

Treatment

  • Well over 90 percent of these tumors go away within six months by following a daily regimen of stretching exercises, and repositioning procedures that an ENT will recommend.[1:14]

  • Sometimes, an ENT arranges a visit with a physical therapist, to demonstrate the exercises and to work with the parents until they are well-practiced with the exercises.[1:15]

  • In a small percentage of SCM tumor of infancy cases, surgery is necessary.[1:16]

  • There are a variety of factors that help guide an ENT’s treatment decision, including:

    • The age of your baby
    • The findings from the ultrasound, which can help to predict how well the SCMI will respond to stretching exercises.
    • The severity of the SCM tumor of infancy
    • The ability of caregivers to consistently perform the exercises and repositioning procedures
    • A diagnosis of a flat spot on your baby’s head
    • Whether your baby has facial asymmetry or other bodily deformities
    • Whether your baby’s motor skills are affected by the SCM tumor of infancy
  • Passive stretching exercises.[1:17]

    • They involve gentle passive range of motion and strengthening exercises for your baby’s neck.[1:18]
    • Success of the exercises depends upon properly holding your baby by the shoulders and positioning your hands in the right spots, as well as the proper execution of them.[1:19]
    • Often two caregivers are needed to rotate your baby’s neck to the side of the affected muscle, while the other caregiver is holding your baby in place. Gentle, firm pressure is applied and the neck is rotated to its limit and held for several seconds. The procedure is generally repeated 10 times, twice daily.
  • Repositioning procedures.

    • These involve active range of motion exercises. Also, the physical therapist will demonstrate ways to handle, feed, carry, play with and position your baby as well as ways to encourage proper posture.[1:20]
  • Massage. A special method of massage can increase pain-free range of motion.[1:21] Customized corrective helmet or molding cup for a baby who has a flat spot on his head in addition to the SCM tumor of infancy.

  • Surgery is generally considered if SCM tumor of infancy persists after a year despite stretching exercises and other non-invasive treatment measures.[1:22]

  • Other considerations for surgery: your baby’s neck continues to have significant range of motion problems after six months of exercises or your child is older upon diagnosis of SCMI.[1:23]

  • The surgical techniques vary slightly depending on the SCM tumor of infancy and involve cutting, manipulating, lengthening and then stitching muscles in order to correct them.[1:24]

  • Surgery often requires a neck collar and physical exercises for several weeks or months afterwards.[1:25]

  • In about half the cases, SCM tumor of infancy goes away naturally, within a year or so, without any treatment at all.[1:26]

  • In many other cases, however, untreated SCM tumor of infancy leads to deformities in the head, neck, back, and even hips.[1:27]

  • The severity of the SCM tumor of infancy is a major factor in whether deformities will result or have already appeared in a newborn.[1:28]

  • Even significant cases of SCM tumor of infancy can go away by consistently following a regimen of stretching and repositioning exercises.

  • Only a highly trained ENT can help to assess and predict how well any particular case of SCM tumor of infancy will respond to exercises.[1:29]

  • More severe cases of SCM tumor of infancy are successfully corrected through surgery; an exercise regimen and a cervical collar are generally recommended for a period of time.[1:30]

  • Occasionally, regardless of the severity of your baby’s SCM tumor of infancy, your child’s posture may temporarily return to a more “twisted” state; this can happens during periods of growth, illness, teething, and development of new motor skills.[1:31]


  1. Title: Sternocleidomastoid Tumor of Infancy
    Publication: The Children’s Hospital of Philadelphia: DIVISION OF OTOLARYNGOLOGY (EAR, NOSE AND THROAT) ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎ ↩︎