Cervical Dystonia

General Information



  • Sternocleidomastoid spasm or dystonia
  • Torticollis is a broad category of disorders categorized by involuntary movement or abnormal posturing of neck (head tilt and rotation)
  • Torticollis derived from Latin words tortus (twisted) and collum (neck)

Also called:

  • Spasmodic torticollis
  • Idiopathic spasmodic torticollis
  • Sternocleidomastoid spasm


  • Torticollis is twisting of neck (rotational)
  • Other forms of cervical dystonia include laterocollis (side bending), anterocollis (flexion), retrocollis (extension) or combinations

Organs involved:

  • Sternocleidomastoid spasm, sometimes associated with rotatory subluxation of C1 on C2 (atlanto-axial subluxation)

Who is most affected:

  • Adults
  • Usual age of onset 30-50 years


  • Incidence and prevalence based on population data from Rochester, Minnesota (1950-1982)
    • Annual incidence of generalized dystonia 2 per 1,000,000 persons
    • Annual incidence for all focal dystonias combined 24 per 1,000,000 persons
    • Prevalence of generalized dystonia 34 per 1,000,000 persons
    • Prevalence for all focal dystonias combined 295 per 1,000,000 persons
    • Torticollis most common focal dystonia
    • Reference – Mov Disord 1988;3(3):188
  • estimated prevalence of primary dystonia among persons > 50 years old ranges from 30 per million in Chinese survey (Arch Neurol 1985 Jul;42(7):655) to 7,320 per million in Italian survey (Neurology 2002 Sep 24;59(6):941)

Causes and Risk Factors


  • Often idiopathic (Phys Ther 2007 Nov;87(11):1511)
  • Can be secondary to
    • Abnormal birth or development history
    • Drug exposure
    • Neurologic disorder
    • Trauma
    • Reference – Phys Ther 2007 Nov;87(11):1511


  • Localized muscle spasm with involuntary sustained tonic or clonic contractions of neck muscles
  • Involuntary concomitant contraction of agonist and antagonist muscles

Likely risk factors:

  • Psychopathological antecedents and association with stressful life-events common in retrospective study of 220 patients with isolated and idiopathic spasmodic torticollis (Can J Neurol Sci 1991 May;18(2):143)

Complications and Associated Conditions


  • cervical dystonia had a significant negative impact on quality of life in cohort of 289 patients (Mov Disord 2002 Jul;17(4):838)

Associated conditions:

  • 41.3% of patients met DSM-IV criteria for current social phobia in prospective cohort of 116 patients with spasmodic torticollis treated with botulinum toxin (J Neurol Neurosurg Psychiatry 2001 Oct;71(4):499), commentary can be found in J Neurol Neurosurg Psychiatry 2002 Oct;73(4):461
  • Associated movement disorders in study of 300 patients with cervical dystonia
    • 82% had torticollis, 42% had laterocollis, 29% had retrocollis, and 25% had anterocollis
    • 66% had combination of abnormal postures
    • 71% had tremor (60% had head-neck tremor)
    • 68% reported local pain
    • 39% had scoliosis
    • 32% had evidence of secondary cervical radiculopathy
    • may be associated with other movement disorders
      • 16% had oral dystonia
      • 12% had mandibular dystonia
      • 10% had hand/arm dystonia
      • 10% had blepharospasm
    • Reference – Neurology 1991 Jul;41(7):1088