Sternocleidomastoid (SCM) Muscle Guide

• The content provided is a muscle guide for the Sternocleidomastoid (SCM) muscle, torticollis, cranial deformities, and associated interventions.

SCM Muscle

• Originates from the mastoid process of the temporal bone and the lateral half of the superior nuchal line.
• The sternal head inserts on the manubrium of the sternum.
• The clavicular head inserts on the medial third of the clavicle.
• Innervated by the spinal accessory nerve for motor function, and C2/C3 for pain and proprioception.
• Bilateral action causes cervical flexion and capital extension.
• Unilateral contraction results in ipsilateral sidebending/lateral flexion and contralateral rotation of the neck.

Unilateral SCM Contraction

• Right SCM contraction leads to right sidebending and left rotation.
• Left SCM contraction leads to left sidebending and right rotation.

Congenital Muscular Torticollis (CMT) Naming

• Right torticollis involves the right SCM, resulting in right lateral flexion and left rotation, with limited left lateral flexion and right rotation.
• Left torticollis involves the left SCM, resulting in left lateral flexion and right rotation, with limited right lateral flexion and left rotation.

Types of Torticollis

• Postural torticollis involves a postural preference of cervical lateral flexion and/or rotation, but muscle flexibility and ROM are normal.
• Muscular torticollis involves cervical lateral flexion and/or rotation with SCM tightness and ROM limitations.
• SCM mass involves cervical lateral flexion and/or rotation with fibrotic thickening of the SCM (palpable mass/bump) and ROM limitations.
• CMT with SCM mass is a congenital, benign, nontender fibrous tumor in the SCM, associated with breech presentation or forceps/vacuum delivery.

Torticollis Risk Factors

• Large baby
• Multiple babies
• Breech position
• Birth trauma
• Vacuum or forceps delivery

Untreated Torticollis Complications

• Craniofacial deformities
• Asymmetrical postures
• Developmental delay
• Plagiocephaly
• Asymmetrical ears (one anterior and one posterior)
• Uneven eyes
• Cervical &/or thoracic scoliosis
• Uneven shoulders
• Uneven weight bearing through pelvis
• Children diagnosed with CMT are at risk for motor developmental delays

Importance of Screening

• Up to 18% of children with asymmetrical head and neck posture may have a non-muscular cause.
• Establishing an accurate diagnosis is essential

Torticollis Differential Diagnosis

• Klippel-Feil Syndrome
• Ocular Torticollis
• Benign paroxysmal torticollis
• Sandifer syndrome
• Neurological causes

Klippel-Feil Syndrome

• Abnormal fusion of 2 or more cervical vertebrae (Red Flag).
• Associated with short neck, low hairline, cervical spine ROM limitations.
• May also involve kidney, rib & heart abnormalities, hearing problems, congenital scoliosis.

Ocular Torticollis

• Compensatory abnormal head/neck posture used to improve vision &/or maintain binocular vision.
• Onset is later than CMT
• Neck ROM is not limited
• Usually associated w/ nystagmus or strabismus
• Screen by checking oculomotor function (visual tracking, smooth pursuit)

Benign Paroxysmal Torticollis

• Recurrent episodes of head tilt to the same or opposite side.
• Accompanied by nausea, vomiting, crying and migraines later in life.

Sandifer Syndrome

• Recurrent episodes of dystonia of the neck (R cervical rotation) with back arching, especially after eating.
• Occurs secondary to GERD, a position of comfort for infants with reflux.

Neurological Causes of Torticollis

• Screen for brachial plexus injury (head turned away from affected UE), CNS lesions (tumors in brain, brainstem, cerebellum).
• Pain with movement (CMT is not painful).
• Atypical or asymmetrical muscle tone and retained primitive reflexes.
• Signs of brachial plexus injury (decreased movement &/or posturing of one UE, decreased sensation in an UE).

Torticollis Subjective History

• Chronological age (corrected if premature) and age of symptom onset.
• Pregnancy and birth history (fetal movement, multiple pregnancies, cephalic or breech, forceps or vacuum, low birth weight).
• Head posture/preference & head or facial asymmetry.
• Other known/suspected congenital, developmental, or medical conditions.
• Developmental milestones.

Torticollis Associated Conditions Screening

• Cranial deformities
• Developmental dysplasia of the hip
• Brachial plexus injury
• Foot deformities
• Early motor delays
• TMJ dysfunction

Torticollis Examination-Systems Review

• Musculoskeletal (symmetrical face, skull, spine, shoulders, hips, symmetrical ROM, SCM palpation).
• Neurological (tone, BPI, temperament, visual tracking).
• Integumentary (skin folds of hip and neck symmetry, color, condition).
• Cardiopulmonary (rib cage expansion, clavicle movement).
• Communication (facial expression, cry).
• Movement (symmetrical and full AROM in all positions).
• G-I (Hx of GERD or difficulty feeding from one side).

Developmental Dysplasia of Hip Risk Factors

• Breech birth
• Large babies
• Cultures that swaddle
• Signs/Sx: asymmetrical skin folds, hip popping/clicking, limited hip ABD ROM, leg length discrepancy

Torticollis Examination-Body Structures

• Bilateral cervical AROM of lateral flexion and rotation.
• Bilateral cervical PROM of lateral flexion (110°) and rotation (70°).
• Posture in and tolerance to supine, prone, sitting, and standing.
• PROM/AROM of trunk, UEs, LEs.
• Pain or discomfort.
• Skin integrity, SCM mass.
• Craniofacial asymmetry & head/skull shape.

Muscle Strength of Lateral Flexors measured by Muscle Function Scale (MFS)

• 0: Below the horizontal line (0° to 15° to >45°).
• 4: High above the horizontal line, more than 45° (>45° to 75°).

Norms for Muscle Function Strength/Endurance at Ages

• 2 months: Mean 1.0, Range 0-2.
• 4 months: Mean 2.6, Range 1-4.
• 6 months: Mean 3.0, Range 2-4.
• 10 months: Mean 3.4, Range 3-4.

Torticollis Examination-Participation

• Positioning when awake & asleep.
• Time in prone when awake.
• Ability to alternate sides when breastfeeding or bottle feeding.
• Time spent in equipment/positioning devices.

Torticollis Prognosis

• PT starts before 1 month, often 1x/wk.
• Most important aspect of PT=>caregiver education.

First Choice Interventions for CMT

• Neck PROM when PROM is limited
• Neck & trunk AROM
• Developmental of symmetrical movements
• Environmental adaptations
• Caregiver education

Neck PROM

• Should be performed frequently throughout the day
• Slow, gentle, pain-free stretches
• Stabilize head & shoulders to prevent compensations
• Can be performed in a variety of positions
• Contraindications to PROM: c-spine bony abnormalities, clavicle fracture, tumors, Arnold-chiari malformation

Neck & Trunk AROM

• Goal: strengthen neck and trunk muscles
• Activities: positioning, carrying, eating & play
• Cervical Rotation: Visual tracking to non-preferred side, feeding from non-preferred side
• Cervical lateral flexion: practice righting reactions to non-preferred side
• Minimize time in positioning devices & encourage prone play

Development of Symmetrical Movements

• Facilities symmetrical age-appropriate motor skills
• Prevent asymmetry with prone, sitting, crawling & walking
• Transition to the right and left b/w all developmental positions

Environmental Modifications

• Alternate infant’s position in crib & changing tables
• Minimize time in positioning devices
• When used, positioning devices must be used with attention to infant symmetry & encourage cervical rotation to the non-preferred side
• Maximize awake time in prone (goal=at least 1 cumulative hour of tummy time per day)

Caregiver Education

• Educate about:
  • CMT
  • Tummy time when awake
  • Minimize time in infant positioning equipment
  • Alternate sides when feeding
• Create individualized home program with family structure & schedule in mind

Torticollis Outcomes & PT Discontinuation Criteria

• Cervical PROM is within 5° of the unaffected side.
• Symmetrical movement patterns are present.
• Age-appropriate gross motor skills are present.
• No visible head tilt.
• Caregivers demonstrate understanding of how to monitor their child as they grow.

Reassessment After Torticollis Treatment

• Re-assess 3-12 months after discontinuation or when the child starts walking.
• Assess postural symmetry, functional abilities, caregiver understanding of home exercises/monitoring, and caregiver satisfaction.
• If all criteria met, discharge from PT; if not, restart direct PT services.

Notes on Intermittent Head Tilt

• May return with illness, fatigue, or when learning a new motor skill.

Cranial Deformation

• Distortion of head shape due to mechanical forces prenatally or postnatally.
• Associated with CMT, prematurity, multiple births, firstborn children.
• Increased incidence after 1994 "Back to Sleep" campaign.
• Decreased time in prone and increased time in supine
• 80% of brain/skull growth occurs before 12 mos of age.
• Skull is most malleable prior to 3 mos of age and brain growth slows at 5-6 mos.

Types of Cranial Deformation

• Plagiocephaly: Ipsilateral occipital flattening & contralateral occipital bossing
• Brachycephaly: Central occipital flattening
• Dolichocephaly: Long & narrow skull

Positional/Deformational Plagiocephaly

• Asymmetrical head shape and facial asymmetry-parallelogram shape.
• Jaw, ears & eye mal-alignment (ear on posterior flat side moves anterior).
• Associated with CMT, prematurity, multiple births.

Craniosynostosis (Red Flag)

• Premature closure of one or more cranial sutures causing cranial asymmetry.
• Sx: slow or no head growth.
• Raised ridge on skull along suture and abnormal skull shape.
• Positional Molding: frontal protuberance, ear displaced anteriorly, flattened occiput, all sutures open, posterior protuberance
• Lambdoid Synostosis: frontal protuberance, ear displaced posteriorly, mastoid protuberance, closed lambdoid suture, posterior protuberance

Craniofacial Assessment

• Palpate anterior and posterior fontanelles (size, shape, position, fullness).
• Palpate cranial sutures (look for ridging).
• Visual assessment of craniofacial symmetry (take photos of 6 views) or use standardized assessment.
• Reassess monthly.

Cranial Deformation Evidence Based Recommendations

• Decrease pressure on flat spots by encouraging more tummy time and less time in positioning equipment.
• Treat CMT, if present.
• Cranial molding helmets initiated when skull is rapidly growing (4-6 months), worn 20-23 hours per day.
• Poorer outcomes associated with older age, greater severity, and poor adherence.