DEFINITION AND STATE OF THE PROBLEM:
Benin generally and very rarely disabling, tremor is the most common movement disorders. He is a mechanical oscillation produced by periodic muscle activity takes its origin in the central nervous system. J. Dejerine defines in 1914 by “involuntary rhythmic oscillations that describes all or part of the body around its equilibrium position.” The tremors are among the most common neurological manifestations. There are many forms both their headquarters and their appearance and their circumstances ballistics.
By definition, are excluded epileptoid the thrill and trepidation. The steps of the practical approach before an earthquake are summarized in Box 1.
Box 1. Ten steps to support a tremor
1. To affirm its nature (differential diagnosis)
2. Determine its physiological or pathological nature
3. The grade according to its appearance circumstances
4. Clarify its topography
5. Evaluate the functional impairment
6. Search for neurological and psychiatric field
7. Verifi er the list of drugs and toxic administered
8. Determine the etiologic diagnosis
9. Check the contributing factors
10. Submit a symptomatic therapy and / or adapted etiological
Affirm the existence of an earthquake is seldom difficult. The majority of them are permanent or frequently present, and the practitioner is able to observe them. More rarely, some patients have reported an intermittent tremor, unrecognized by the doctor itself.
It is then necessary to verify the nature of the abnormal movement by a specific examination, if necessary by making mimic the patient, the latter may refer to as tremor other abnormal movements such as bursts of myoclonus, dyskinesia in dopaminergic treatment, etc. Episodic tremor integrating into a rich vegetative functional semiotics fact evoke panic attacks or hypoglycemia access.
Once recognized tremor, the next logical step is the determination of its pathological character or not. A physiological tremor is present in all healthy individuals in maintaining an attitude at all the muscles or joints with a degree of freedom. It is fast oscillations of low amplitude, bilateral and symmetrical, often imperceptible, which provide (by definition) no functional impairment.Their product exaggeration distal attitude tremor prominent senior members, more or less regular.Physiological tremor is accentuated by emotions (such as stage fright), prolonged physical exertion, fatigue, numerous metabolic disorders (hyperthyroidism, hypoglycemia, fever, discharges catecholamine pheochromocytoma, etc.) and under the influence of some toxic drugs.
In these situations, the intensity of the tremor was originally a functional impairment in daily activities, it takes a pathological dimension. If the eviction of drugs that aggravate and the possible associated metabolic disorders corrections are insufficient, it may be occasionally mitigated by small doses of propranolol (Avlocardyl®, 10 to 40 mg).
In general, like all abnormal movements, tremors have a fluctuating intensity with changes in muscle tone and all are aggravated by emotion. In practice, any tremor felt as invalidating should be considered pathological and can legitimate medical intervention. When reason for consultation, tremor pose few diagnostic problems because the patient usually can describe with relative accuracy Headquarters, circumstances of occurrence and the resulting functional impairment. The most delicate problem is the therapeutic attitude, which depends on both the functional discomfort felt, tolerance drug (or necessity if they are involved) and the variability of situations.
The physical, must be added the psychological impact of the quake that vehicle demeaning images such as frailty, senility or alcoholic stigma, and pose a social problem facing or professional acceptability. Convince the patient and his family’s distinctiveness between tremor and neurological decline is in itself a source of relief.
It is common, for useful diagnostic orientation in clinical practice to classify earthquakes according to their circumstances of occurrence in the range of muscle tone in which they predominate.
Resting tremor occurs when the muscle where it seat is released and disappears with muscle activity. To detect it, sometimes with a slight latency installation, facilitating or tripping operations are often useful. Puffs of oscillations of the fingers and wrist are sought in a sitting position (drooping hands and forearms on thighs or forearms resting on the armrests of the seat) or supine, during a mental arithmetic test or story evoking emotional memories, as well as walking. When writing or tapping tests (repetitive movements of the clip-index and thumb open-close fist), observation of the contralateral hand in release position may reveal an intermittent tremor.
The working diagnosis is easy: any predominant tremor or exclusively present at rest is part of a parkinsonian syndrome.
The two main causes for this are Parkinson’s disease and consumption of drugs neuroleptic properties. The search for a akinétohypertonique syndrome, gait and writing is associated with systematic result.
Moreover, the discovery of a parkinsonian syndrome in young adults (<40 years) must always consider Wilson’s disease to the extent that a delayed diagnosis can have disastrous consequences in this condition.
In Parkinson’s disease, tremor occurs at rest, is absent during sleep and is accentuated in the morning. It is asymmetrical and begins at the distal segment of upper limb, before spreading to the ipsilateral side of the body and then to bilateralize, touching the chin and tongue. He still predominates in the place where it started, and saving the neck, voice and trunk.
Moderate, it is intermittent and readily triggers a few seconds after an emotion.
Intense or during the ascent phase of dopaminergic therapy, a runaway phenomenon of large amplitude may be extended to maintain an attitude.
For treatment, symptomatic referred, we refer to the current recommendations, not forgetting to press the patient on the drug-sensitive nature of the disease, and thus the expected improvement. Contrary to popular belief, there is no specific effect of anticholinergic or piribedil (Trivastal®) on tremor, the drug most effective anti-Parkinson remaining L-DOPA. It is important to note further that the establishment of an anti-Parkinson treatment after the age of 70 consists of first-line prescription of L-DOPA and not of dopamine agonists, anticholinergics or other products. If severe tremor, dopamine impregnation of several weeks to relatively high doses necessary to achieve a substantial improvement.
In other degenerative parkinsonian syndromes, tremor is often in the background and less asymmetric. It is less sensitive to levodopa in the presence of akinétohypertoniques elements as in Parkinson’s disease.
Earthquake in neuroleptic:
If parkinsonism under neuroleptics, tremor is present about half the time. If certain features have been described in order to distinguish iatrogenic Parkinsonism and Parkinson’s disease, all can be at fault in a given patient, the only two elements characteristic of neuroleptic impregnation consisting reality akathisia (inability to stand still) and oral-facial-lingual dyskinesia.
Search for hidden or taken neuroleptics self-medication should be systematic before any parkinsonism.
Some simple facts need to be highlighted here:
– Unlike tardive dyskinesia, parkinsonism is always reversible upon discontinuation of the product;
– Tremor is relatively dosedépendant;
– If an attenuation of parkinsonian symptoms occurs within days after dose reduction or discontinuation of the drug, their complete disappearance can take several weeks or even months, what patients should be warned;
– All former or recent neuroleptics, some hidden (Théralène®, Vésadol®, Sibelium®, Agréal®, Primperan®, Vogalène®, Noctran®, Mépronizine®, etc.) can cause a parkinsonian tremor, including atypical molecules as Leponex® and even products “neuroleptiques- like” such as tetrabenazine (used for the treatment of tardive dyskinesia);
– A parkinsonian syndrome that persists 6 months after discontinuation of neuroleptics is (also) related to another cause, usually idiopathic Parkinson’s underlying disease.
EARTHQUAKE OF ATTITUDE AND ACTION:
The tremor attitude or posture, is observed in the active maintenance of a fixed attitude and disappears when complete muscle relaxation. The tremor action occurs in the movement, and intensified with the effort of attention, sight and accuracy. The term intention tremor is usually reserved for large amplitude tremors affecting the upper limb root which affect all gestures are often referred to as dyskinesia or hyperkinesia volitional. Many tremors coexist in attitude and action. For example, an earthquake of moderate attitude sitting on the distal segment of a member is also evident in the action when it intensifies and diffuse the proximal segment.
Before a patient consultant for a tremor of attitude and action, two etiologies dominate widely: essential tremor and iatrogenic tremor.
This is the earthquake but also the most common involuntary movement in the general population. The terminology “senile tremor” pejorative and inaccurate, has become obsolete. A family character is found in more than half the cases, according to an autosomal dominant with incomplete penetrance and variable expressivity. The disease moved to the fifth or sixth decade, more rarely in children or young adults. The tremor occurs in the attitude and action, and sits preferentially in the upper limbs (where it is roughly symmetrical), neck and larynx. Always isolated, it worsens slowly thread the years on a more or less linear fashion in both its intensity as his body topographic extension.
Inconstantly a remarkable sensitivity to small doses of alcohol is reported by patients, some of whom are reluctant to discuss the phenomenon for fear of being considered alcoholics. International diagnostic criteria for essential tremor are shown in Box 2.
Box 2. Diagnostic criteria for essential tremor
Earthquake bilateral, postural location, involving the hands and forearms (predominantly distal), visible and persistent, eventually discreetly asymmetrical; can shake the head and the associated voice
Disease duration at least equal to 5 years
Absence of other neurological, trauma of the nervous system in the 3 months preceding the installation of earthquake
Lack of exposure and recent trémorigènes or toxic drug withdrawal
No obvious psychic etiologic field
Absence of acute onset or evolution by jerks
The classic maneuvers seeking a tremor of attitude and action in the upper limb is the attitude of the oath (hands open arms outstretched, palms down), maneuvering the swashbuckler Garcin (maintaining two indexes face face before the nose, spaced 1 cm horizontal arm and forearm, shoulder elevation 90 ° and elbow flexion), the finger-nose test and graphomotor tests (writing, drawing spirals or lines curves). If necessary, the patient is asked to pour water from a bottle into a glass, the accuracy of the test and the emotion induced by the fear of failure strongly accentuating the quake. Involvement of cervical muscles, rarely isolated, is visible during maintenance by rhythmic oscillations of the head in affirmation or negation. The quavering voice is detected during the conversation or request the patient to sing a note held seconds.
After making the diagnosis and announced it is useful to begin with reassurance regarding the benign and low scalability of the disease from which he suffers. Despite these factors, pharmacological treatment is often disappointing and allows only alleviate the tremor of significant drawbacks price (penalty taken daily, adverse effects, possibility of addiction).
Propranolol (Avlocardyl® between 60 and 320 mg / day) and primidone (Mysoline®, between 250 and 750 mg / day) are the first line of products and are established by progressive steps. If the tremor is well tolerated in everyday life, some patients may not have recourse to a “premedication” in public circumstances where it is amplified by emotion.Impregnation for a few hours or days by alprazolam (Xanax®, between 0.75 and 2.75 mg / day) or propranolol or it must be said, ingesting a small amount of alcohol a hour before the simulation exercise (often with a rebound in the waning) may then be proposed. The other drugs, the use of botulinum toxin into the muscles of the shoulder girdle and exceptional indications for thalamic stimulation surgery are the responsibility of the specialist.
Before any tremor of attitude and action, you should consult the patient’s orders (and possibly the Vidal dictionary) and seek self-medication. In general, the consultation (s) order (s) of the patient is (are) a systematic and often fruitful gesture before any abnormal movement.
When a drug is suspected, the dosage reduction, discontinuation of the molecule or therapeutic class change is obviously desirable if possible. The most frequently involved in clinical practice molecules are tricyclic antidepressants and inhibitors of serotonin reuptake, sodium valproate, corticosteroids and amiodarone.
Lithium and cyclosporine are accompanied frequently quake but are less widely prescribed.
Intermittent or permanent, psychogenic tremor may be considered in an atypical presentation and according to clinical criteria summarized in Box 3.
Box 3. Elements of psychogenic tremor suggestive
sudden onset and / or occurrence of spontaneous remissions
unusual combination of tremor at rest and attitude / share
amplitude decrease or disappearance during maneuvers of diversion of attention
frequency variations and / or seat during maneuvers of diversion of attention or during voluntary movements of the contralateral hand
Exaggeration when attention or eyes are worn on the earthquake
Coactivations muscle visible or palpable antagonist muscles
medical history of somatization (somatoform disorder)
The diversion of attention is achieved by simply questioning or multiple motor activities such as walking, writing or drawing. A sensitive test involves asking about maintaining indexes and upper limbs outstretched in front of him, and write his name in the air (possibly in reverse) with an index and then the other. We then see the finger remained fixed oscillate initially, to stabilize during the year, and then get back to swing the waning when attention is transferred to the maintenance of attitude. On a shaky limb, coactivation phenomenon results in the perception of intermittent resistance to passive movement of a joint (print struggle with the patient). A disappearance of the tremor is observed when the patient oppose this resistance or conversely when it relaxes completely. The search for other functional manifestations (erratic abdominal pain, asthenia, dizziness, headache, back pain, etc.) is an additional element in favor of psychogenic tremor.
If necessary, an electrophysiological recording with standardized tests performed in a specialized center confirms the inorganic elements (intensity and frequency variability, drive phenomenon of rhythm, etc.). A secondary benefit claim or a more or less conscious associated with it. One difficulty is that in many subjects, functional overload is grafted onto an authentic organic tremor underlying that can meet a specific treatment. Psychological support is usually tricky.
Other causes that can bring the patient to consult (cortical tremor, dystonia trembling function quake, tremor Holmes, etc.) justify a specialized consultation. An isolated and focal tremor enables its only seat a rapid diagnostic orientation.
Earthquake isolated without complaint:
The practitioner may also notice when maintenance or clinical examination for another reason, an isolated tremor does not hinder the patient. Abstention is then put because, apart from Wilson’s disease drugs reported above have only referred symptomatic and processing time does not affect the prognosis of a tremor. We can compare this situation the distal end myoclonic tremor of certain cortical dementia called “minipolymyoclonus” whose patients do not usually complain. It is not a useful generally attract the attention of patients on their trembling, because of the psychological impact that can induce the idea that it is easily visible.
It has the distinction of being the source of a very particular complaint, knowledge avoids unnecessary consultations and explorations. This is a very fast tremor of the lower extremities, absent lying or crouching position, occurring at the station and stand still fading in the march. The patient is usually reported a balance disorder, and postural instability or print gives the impression of being afraid of falling to the immobile standing more or less prolonged (queue in a shop, withdrawal money to the distributor, etc.). There is therefore a clinical situation, finally uncommon in neurology, of astasia (inability to keep upright) without abasia (more or less complete loss of walking without a neurological deficit in muscle strength). Faced with this complaint, it may be legitimate to start by searching for systematic basis orthostatic hypotension.
Electrophysiological recording confirms the diagnosis of orthostatic tremor before initiating treatment with clonazepam.
Careful and prudent clinical judgment is sufficient for the diagnostic approach to the majority of tremors. The use of imaging is relatively rare (search for hydrocephalus and thalamic tumor in children; tumor or vascular injury frontal and basal ganglia lesion midbrain or adult) and is never useful before neurological expertise.
Therapeutically, special attention is given to drugs and potentially toxic iatrogenic. The prescription of dopaminergic therapy test is always useful to a resting tremor, except in subjects impregnated by neuroleptics.