Dystonia
Introduction/Definition[edit | edit source]
Dystonia is a hyperkinetic movement disorder in which involuntary contractions of muscles occur. It is characterised by sustained muscle contractions and abnormal trunk, neck, face, arms, and legs postures.[1]The term "Dystonia" was coined by Oppenheim in 1911 to express the disorder of changing muscle tone and repetitive muscle spasms. Its original name was dystonia musculorum deformans which was later changed to torsion dystonia due changing understanding of the problem.
Dystonia is easily confused with other diagnoses such as spasticity and rigidity.[1]This condition can be present separately or in combination with chorea, myoclonus, tremor and parkinsonism.[2][3]
According to Movement Disorder Society, there are 3 more sub-definitions of Dystonia-
- Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions causing abnormal and often repetitive, movements, postures, or both.
- Dystonic movements are typically patterned, twisting, and may be tremulous.
- Dystonia is often initiated or worsened by voluntary action and is associated with overflow muscle activation.[3]
Epidemiology[edit | edit source]
- True prevalence of Dystonia still remains unclear due to the fact that this disorder encompasses a wide range of classification.[4] Although it's not rare to see dystonia in neurologically affected populations.
- Patients with dystonia represent ~20% of patients in movement disorder clinics.[5][6][7]
- Dystonia cases accounts for 15-30 cases per 100,000 in general population.[8][7][4]
- In a study of a random sample of the population over 50 years of age, the prevalence of isolated dystonia was concluded to be 732 per 100 000, suggesting that in the ageing population dystonia is a common neurological disorder.[4][9]
- Women are more likely to be affected with this condition than men with a ratio of 2:1.[4]
- Adult-onset focal dystonia syndromes are by far the most frequent presentations of this disease. In recent researches on focal syndromes, the majority of patients had cervical dystonia (69%) or blepharospasm (17%) whilst other forms were much rarer: limb dystonia (3%–7%), spasmodic dysphonia (1%–3%), musician’s dystonia (3%) and oromandibular dystonia (1%).[4]
Quality of life[edit | edit source]
A lot of researches have investigated the health-related QOL in patients with dystonia and indicated a poorer QOL in patients with dystonia. Several factors affect QOL in patients, including impaired physical functioning owing to the presence of motor symptoms. The most severe, generalized forms of dystonia can affect all activities of daily living such as walking or hand function.
Focal forms of dystonia can also be disabling; for instance, laryngeal dystonia can affect communication, and blepharospasm can impede safe driving or walking. Task-specific dystonia can impede professional occupations, for example, in patients with writer’s cramp or musician’s dystonia.
Aetiology/Causes[edit | edit source]
Classification[edit | edit source]
Pathophysiology[edit | edit source]
Clinical features[edit | edit source]
There are 5 classical signs of Dystonia:-
- 2 main physical signs- dystonic movements and dystonic posture.
- 3 additional physical signs -mirror dystonia, overflow dystonia, and gestes antagonists/sensory tricks.
Examination[edit | edit source]
Diagnosis[edit | edit source]
Investigation[edit | edit source]
Screening and Prevention[edit | edit source]
Treatment[edit | edit source]
References[edit | edit source]
- ↑ 1.0 1.1 Tarsy D, Simon DK. Dystonia. New England Journal of Medicine. 2006 Aug 24;355(8):818-29.
- ↑ di Biase L, Di Santo A, Caminiti ML, Pecoraro PM, Di Lazzaro V. Classification of Dystonia. Life. 2022 Jan 29;12(2):206.
- ↑ 3.0 3.1 Albanese A, Bhatia K, Bressman SB, DeLong MR, Fahn S, Fung VS, Hallett M, Jankovic J, Jinnah HA, Klein C, Lang AE. Phenomenology and classification of dystonia: a consensus update. Movement disorders. 2013 Jun 15;28(7):863-73.
- ↑ 4.0 4.1 4.2 4.3 4.4 Albanese A, Di Giovanni M, Lalli S. Dystonia: diagnosis and management. European journal of neurology. 2019 Jan;26(1):5-17.
- ↑ Balint B, Mencacci NE, Valente EM, Pisani A, Rothwell J, Jankovic J, Vidailhet M, Bhatia KP. Dystonia. Nature reviews Disease primers. 2018 Sep 20;4(1):1-23.
- ↑ Jankovic J. Treatment of hyperkinetic movement disorders. The Lancet Neurology. 2009 Sep 1;8(9):844-56.
- ↑ 7.0 7.1 Steeves TD, Day L, Dykeman J, Jette N, Pringsheim T. The prevalence of primary dystonia: a systematic review and meta‐analysis. Movement Disorders. 2012 Dec;27(14):1789-96.
- ↑ Camfield L, Ben-Shlomo Y, Warner TT. Epidemiological study of Dystonia in Europe Collaborative Group impact of cervical dystonia on quality of life. Mov Disord. 2002;17(4):838-41.
- ↑ Müller J, Kiechl S, Wenning GK, Seppi K, Willeit J, Gasperi A, Wissel J, Gasser T, Poewe W. The prevalence of primary dystonia in the general community. Neurology. 2002 Sep 24;59(6):941-3.
