Cervical Dystonia Mimics: A Case Series and Review of the Literature

Srinivas Raju; Amogh Ravi; LK Prashanth

doi:10.5334/tohm.465

Figures & Tables

Table 1

Clinical Features and Imaging Findings of Pseudodystonia Subjects

Video 1	Video 2	Video 3
Age at onset	45	Childhood	6	21	11	24
Current age	48	22	6	53	14	24
Gender	M	M	F	M	M	M
Clinical presentation	Neck posturing with neck flexion	Abnormal posturing of neck since childhood	Abnormal posturing of neck following a trauma	Posturing of neck since age of 21. Increased in the last 5–6 months with paraspinal spasm	Abnormal neck movements	Neck posturing and discomfort in left hand (acute onset)
Clinical findings mimicking dystonia	Antecollis with facial dystonia	Torticollis to the right with minimal retrocollis; left SCM is taut and string like	Severe torticollis with right shoulder elevation	Mild torticollis to the left present with features of antecollis	Jerky neck movements (dystonic jerks vs. akathisia)	Lateral shift to the right with right torticaput
Other neurological /clinical findings	Neck extensor weakness (MRC grade 1/5)	Thin and fibrosed left SCM	None	Head drop with neck extensor weakness (G3+/5)	Dysmorphic features	Jerky tremors of hands, bilateral hand grip weakness
MRI findings	Fibrosis with fatty infiltration of deep cervical muscles	Atrophy and fibrosis of the left SCM. Scoliosis the of cervical spine with convexity to the right side	Subluxation of C2-C3	Deep paravertebral muscle atrophy	Increased Atlanto dental distance of 100 mm with retroversion of odontoid process. Signal change and thinning of cord at C1-C2 level. Hypertrophied anterior arch of atlas, hypoplastic odontoid process	Multiple anomalies in CVJ with atlanto occipital assimilation, partial fusion of C1-C2 vertebrae, hemi vertebra with fusion of right C4-C5 level along with C3-C4 spinal cord hyperintensities
Interventions done before diagnosis	Anticholinergics, Benzodiazepines, Dopamine blocker, Botulinum toxin, none	Two sittings of botulinum toxin injections given. Anticholinergics	None	None	Benzodiazepines	None
Final diagnosis	Isolated neck extensor myopathy	Muscular fibrosis	Posttraumatic subluxations	Isolated neck extensor myopathy	Atlanto axial dislocation	CVJ anomaly
Intervention after diagnosis	Medical management and supportive care	Option for surgical release given. Patient opted for no intervention	Surgical corrections	Medical management and supportive care	Surgical correction	Surgical referral

[i] Abbreviations: CVJ, Craniovertebral Junction; MRC, ; SCM, Sternocleidomastoid Muscle.

Video 1

Video Shows Neck Antecollis along with Lower Facial Movements. In the second part of the video, clinical examination shows difficulty in neck extension movements against gravity.

**(A) T2WI Axial Section of cervical Spine Shows Atrophied Deep Paracervical Muscles with Fibrosis and Fatty Infiltration.** (B) T2WI axial section of the Neck showing the atrophied left sternocleidomastoid muscle (yellow line-1) in comparison to the normal right sternocleidomastoid muscle (Yellow line-2). (C, D) T2WI Sagittal MRI (C) of CVJ area and sagittal CT section cranio-cervical junction (D) showing multiple anomalies in CVJ with atlanto occipital assimilation, partial fusion of C1-C2 vertebrae, hemi vertebra with fusion of right C4-5 level along with C3-C4 spinal cord hyperintensities.

Video 2

Video Shows Limitation of Rotation of Neck to the Left Along with Right Lateral Shift Torticaput to the Right. The prominence of sternocleidomastoid at its origin can be easily appreciated on the left side.

Video 3

Video Shows Right Lateral Shift of Neck Along with Left Shoulder Elevation. In addition, limitation of rotatory movements of neck to both right and left is shown.

Table 2

Cause of potential mimics of isolated idiopathic cervical dystonia Pseudodystonia

Classification	Causes
Vascular causes	Spinal epidural haemorrhage Cerebellar infarct/haemorrhage Lateral medullary infarct Cerebral haemorrhage Bilateral Putaminal haemorrhage Cerebral AVM Unilateral hypoplasia of Internal Carotid artery ACOM Vascular pseudo retrocollis
Musculoskeletal	AARS Fibrodysplasia ossificans Acute calcific tendinitis Basillar invagination Chiari 1 malformation Klippel-Fiel syndrome Syringomyelia Diastometomyelia Osteomyelitis Inter vertebral disc calcification Facetal hypertrophy Ankylosing spondylitis Fibromatosis of sternocleidomastoid Nodular fascitis of sternocleidomastoid Congenital oseous c2-c3 synostosis Cervical spondylo discitis Osteoporotic fracture Absent sternocleidomastoid muscle
Infections	Septic arthritis Cat scratch disease Tuberculoma Bacterial meningitis Acute febrile torticollis Acute encephalomyelitis Paravertebral Brucellar abscess Cervical epidural abscess Pharyngeal abscess Retropharyngeal abscess Sternocleidomastoid abscess Pyomyositis of paraspinal muscles Lymphadenitis Tuberculosis of bones & joints
Mass / Space occupying lesions	Tumor calcinosis of cervical spine Intra thoracic malignancy Posterior fossa tumor Arachnoid cyst Spinal cord ependymoma Cervical osteoblastoma Medullary tumor Posterior glioma Ewing’s sarcoma Osteochondroma Giant cell tumor Osteoid osteoma Cervical hemangioblastoma Fibrodysplasia ossificans progressiva Post radiation therapy of carcinoma larynx Cerebellar gangliocytoma Spinal cord astrocytoma Colloid cyst of 3rd ventricle Sternocleidomastoid tumor Cervical eosinophilic granuloma
Traumatic	Odontoid fracture Laminar fracture Condylar fracture C1 dislocation with split atlas Fracture of c2 lamina Brachial plexus injury Post trauma foreign body Pneumomediastinum
Ocular Causes	Congenital Nystagmus Nystagmus Compensation Syndrome Spasmus nutans Oculomotor apraxia Refractive error Blepharoptosis Superior oblique palsy Abducens Palsy Vertically incomitant horizontal strabismus Duane syndrome Brown’s syndrome Double elevator palsy Orbital floor fracture Endocrine ophthalmopathy Congenital fibrosis syndrome Inferior oblique muscle palsy (ocular torticollis)
Otological Causes	Acute Mastoiditis Saccular dysfunction Bezold’s abscess
Gastrointestinal causes	Sandifer’s syndrome
Others	Multiple sclerosis Acute disseminated encephalomyelitis Idiopathic intracranial hypertension Hypereosinophilic syndrome Widespread nevus spilus Parry-Romberg syndrome Moyamoya disease Behcet’s disease Kawasaki disease Goeminne syndrome Langerhans cell histiocytosis Allergy Iatrogenic hypoparathyroidism Congenital muscular torticollis Benign paroxysmal torticollis Grisel’s syndrome Complication of ventriculo-peritoneal shunt Familial Mediterranean fever Foreign body
Psychogenic

[i] Abbreviations: AVM - arteriovenous malformation, ACOM - anterior communicating artery aneurysm, AARS - Atlanto Axial Rotatory Subluxation.

Algorithm for Mimics of Isolated Cervical Dystonia.

Cervical Dystonia Mimics: A Case Series and Review of the Literature

Figures & Tables

Table 1

Video 1

Figure 1

Video 2

Video 3

Table 2

Figure 2

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