Congenital Muscular Torticollis

Shortening/contracture of the sternocleidomastoid (SCM) muscle — occurs in ~0.4% of births. See also neck pain (approach) and acquired torticollis.

Causes

In-utero positioning; abnormal SCM development; birth trauma to the muscle. A small pea-sized lump (pseudotumour) is sometimes felt on the SCM in the first 4 weeks, usually resolving by 6 months. Older children occasionally present with a fibrotic, shortened SCM presumed to be the legacy of an unrecognised sternomastoid tumour in infancy.

Presentation

Head held tilted to one side, presenting mostly in the first year of life — often with a history of breech birth or difficult delivery. Over 90% resolve with treatment.

Examination

Tight SCM with restricted neck range of motion; head tilts toward the shortened SCM, chin rotates to the opposite side; a spindle-shaped, firm, painless swelling may be palpable in the affected muscle.

Check for associated conditions: plagiocephaly, facial hypoplasia, hip dysplasia, positional foot deformities.

Investigations: rarely needed — clinical diagnosis. Ultrasound or X-ray only for an unusual presentation or concerning features (specialist-directed).

Management

Diagnosis is clinical; treatment is highly effective, especially started before 3 months.

• Positioning and activities: feed so the baby rotates the chin to the non-preferred side; position the cot so the baby must turn to the non-preferred side to view the room (babies prefer to look into the room and will actively turn away from a wall, stretching the tight muscle); place toys/draw attention on the non-preferred side during play.
• Physiotherapy referral for further positioning advice, stretches and exercises — also reduces plagiocephaly risk.
• Surgery only if: SCM tightness persists limiting head rotation beyond 12–15 months; SCM tightness with progressive facial asymmetry; or diagnosis is made after 12 months.

Referral

Refer for paediatric physiotherapy for conservative management. Request non-urgent paediatric assessment if the cause is uncertain, tightness persists >12 months (with or without facial asymmetry), diagnosis is late (>12 months), or range of motion remains reduced despite conservative therapy.