Torticollis may be either:
- Dystonic Torticollis
- Non-dystonic or Pseudodystonia
It is a primary focal dystonia which manifests as sustained involuntary contractions of the neck muscles leading to abnormal movements and postures of the head.
Dystonic Torticollis is of the following types –
- PrimaryOR Idiopathic Torticollis –
Idiopathic spasmodic torticollis (IST) is a chronic, progressive form of torticollis classified as a focal dystonia. Abnormalities of basal ganglia (deep seated nuclei of the brain) have been implicated in its pathogenesis, though the exact cause is not known. This torticollis starts with mild posturing but later on becomes severe. It affects the day to day activities of a person. It typically worsens during the first 5 years of onset and then eventually plateaus. It manifests as either fixed form or intermittent jerky form or a combination of both. Spontaneous remission is seen in 20% of patients but it is usually not complete or prolonged. Also, nearly all patients relapse within 5 years.
- Secondary Torticollis – It is not commonly seen.
It can be caused by:
- Focal brain lesions of various origins
- Neurodegenerative disorders
- Metabolic disorders
- Drugs and chemicals that affect the basal ganglia, thalamus and brainstem
- Following peripheral injury [79–81].
Non-dystonic or Pseudodystonia are the disorders that are associated with sustained muscle contractions probably due to reflex mechanisms or reaction to some other disturbance
e.g. Tilting of the head to improve vision in 4th nerve palsy or in hemianopia.
Non-dystonic torticollis can be divided into:
- Congenital Torticollis –cause due to:
- In utero malposition or birth trauma
- Malformations of cervical spine
- Hypertrophy of cervical muscles
- Arnold-Chairi malformation
- Acquired Torticollis- CNS mass lesions, abnormalities of the cervical spine, and local head and neck infections are more likely. Psychiatric causes may occur during adolescence.
- Cervical musculoskeletal abnormalities like AAD, fracture clavicle and scapula
- Infections like cervical spine osteomyelitis
- Neurological causes like syringomyelia, tumours
- Other causes like psychogenic, benign paroxysmal torticollis