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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abnormal head movements have been studied in a variety of diseases using objective recording techniques and the data analysed with respect to the frequency content of the movement. Flopping, nodding, tic, chorea, myoclonic jerks, and most head tremors involve frequencies of approximately 2 and 4 Hz which correspond to the natural fundamental and second harmonic resonances of the head as determined by the mechanical properties of the head/neck system. These findings provide a basis for classification of abnormal head movements as well as an explanation of the characteristics of those arising from hypotonia of the neck muscles. The similarities between tremor frequencies and natural resonances suggest that in the case of the head, tremor arises from disorders of neural mechanisms normally responsible for the fine control of voluntary head movement and for stabilisation of the head during disturbance of posture. Head movements in cases of congenital nystagmus were found to be of two types. Some were of bizarre waveform, in no way assisted vision, and were taken to be of primarily pathological origin and classified as tremors. Others were learned adaptive responses which assisted vision either by interrupting the nystagmus, as in the case of spasmus nutans, or by compensating for the nystagmus with an inverse waveform and were called nodding. A prerequisite for true compensatory nodding is modified vestibulo-ocular reflex.
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PMID:Abnormal head movements. 49 Jan 76

Rapid, horizontal, pendular head oscillations were observed in 18 visually impaired children with nystagmus during intense visual fixation, and the characteristics of this behaviour were analysed. Head tilting and eye deviations also occurred in 14 of the children. Their symptoms and signs resembled spasmus nutans. Head shaking appeared to be a voluntary, learned, neurovisual adaptation to improve visual acuity. Accurate simultaneous recordings of eye and head movements are required to understand the pathophysiological significance of these head oscillations.
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PMID:Head shaking by visually impaired children: a voluntary neurovisual adaptation which can be confused with spasmus nutans. 228 5

Two children with congenital stationary night blindness were originally diagnosed as having spasmus nutans. Both children had the typical features of spasmus nutans including asymmetric nystagmus, head shaking, and torticollis. The diagnosis of congenital stationary night blindness was established only after each child underwent electroretinography. The nystagmus associated with retinal disease can mimic many of the features of spasmus nutans. Children suspected of having spasmus nutans should undergo complete ophthalmologic examination and electroretinography if they are myopic.
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PMID:Retinal disease masquerading as spasmus nutans. 835 Oct 22

Tremor in childhood, beginning in the neonatal period, is more common than generally appreciated. Although some tremor disorders in children (eg, essential tremor) also affect adults, others (eg, shuddering, jitteriness, spasmus nutans, and vitamin B12-deficiency tremor) are seen exclusively in children. This review covers the etiology, clinical features, and treatment of the major tremor syndromes in children, and when appropriate, makes comparisons with similar disorders in adults.
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PMID:Tremor in children. 1278 45

This patient, a 26-month-old girl, developed benign neonatal jitteriness soon after birth that subsequently resolved at 3 months of age. At 6 months of age, she developed spasmus nutans with left monocular nystagmus and head shaking in a "no-no" pattern. Physical examination was otherwise unremarkable. Magnetic resonance imaging (MRI) of the brain, optic nerves, and orbits was normal. The spasmus nutans also gradually resolved by 18 months of age. To our knowledge, the co-occurrence of these 2 benign movement disorders in an individual has not previously been reported. The pathogenesis of benign neonatal jitteriness and spasmus nutans is unknown. Their co-occurrence may reflect a shared underlying mechanism.
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PMID:A child with benign neonatal jitteriness and spasmus nutans. 2402 94

Tremor is a common neurological condition in clinical practice; yet, few syndromes are widely recognised and discussed in the literature. As a result, there is an overdiagnosis of well-known causes, such as essential tremor. Many important unusual syndromes should be considered in the differential diagnosis of patients with tremor. The objective of this review is to provide broad clinical information to aid in the recognition and treatment of various unusual tremor syndromes in the adult and paediatric populations. The review comprised of a comprehensive online search using PubMed, Ovid database and Google Scholar to identify the available literature for each unusual tremor syndrome. The review includes fragile X-associated tremor/ataxia syndrome, spinocerebellar ataxia type 12, tremors caused by autosomal recessive cerebellar ataxias, myorhythmia, isolated tongue tremor, Wilson's disease, slow orthostatic tremor, peripheral trauma-induced tremor, tardive tremor and rabbit syndrome, paroxysmal tremors (hereditary chin tremor, bilateral high-frequency synchronous discharges, head tremor, limb-shaking transient ischaemic attack), bobble-head doll syndrome, spasmus nutans and shuddering attacks. Rare tremors generally present with an action tremor and a variable combination of postural and kinetic components with resting tremors less frequently seen. The phenomenology of myorhythmia is still vague and a clinical definition is proposed. The recognition of these entities should facilitate the correct diagnosis and guide the physician to a prompt intervention.
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PMID:Unusual tremor syndromes: know in order to recognise. 2698 48