Movement Disorders Flashcards
Restless Legs Syndrome
Restless legs syndrome (RLS) is a syndrome of spontaneous, continuous lower limb movements that may be associated with paraesthesia. It is extremely common, affecting between 2-10% of the general population. Males and females are equally affected and a family history may be present
RLS - Clinical Features
Clinical features
uncontrollable urge to move legs (akathisia). Symptoms initially occur at night but as condition progresses may occur during the day. Symptoms are worse at rest
paraesthesias e.g. ‘crawling’ or ‘throbbing’ sensations
movements during sleep may be noted by the partner - periodic limb movements of sleeps (PLMS)
85% of patients with RLS have periodic movements of sleep, usually involving the legs (periodic leg movements of sleep [PLMS]). This is characterised by involuntary, forceful dorsiflexion of the foot lasting 0.5-5 seconds and occurring every 20-40 seconds throughout sleep. It is, therefore, worth taking a collateral history from a partner if available.
RLS - Causes and Associations
Causes and associations there is a positive family history in 50% of patients with idiopathic RLS iron deficiency anaemia uraemia diabetes mellitus pregnancy
RLS - Diagnosis
The diagnosis is clinical although bloods to exclude iron deficiency anaemia may be appropriate
Specific DSM-5 criteria for RLS are as follows:
- an urge to move the legs that is usually accompanied by or occurs in response to uncomfortable and unpleasant sensations in the legs, characterized by all of the following: (1) the urge to move the legs begins or worsens during periods of rest or inactivity; (2) the urge is partially or totally relieved by movement; and (3) the urge to move legs is worse in the evening or at night than during the day or occurs only in the evening or at night.
- Symptoms occur at least 3 times per week and have persisted for at least 3 months.
- Symptoms cause significant distress or impairment in social, occupational, educational, academic, behavioural or other areas of functioning.
- The symptoms cannot be attributed to another mental disorder or medical condition (e.g., leg oedema, arthritis, leg cramps) or behavioural condition (e.g. positional discomfort, habitual foot tapping)
- The disturbance cannot be explained by the effects of a drug of abuse or medication
RLS - Ix
Investigations should include excluding iron deficiency (which may potentiate RLS) and you should order sleep studies to characterise the extent of sleep disturbance.
RLS - Mx
First line drug treatments are dopaminergic agents (eg, pramipexole, ropinirole, bromocriptine, levodopa-carbidopa, and rotigotine) or gabapentin/pregabalin. Nonpharmacologic approaches include exercise, avoidance of caffeine, alcohol, and nicotine. Also important to try and stop medications that exacerbate RLS if possible, eg selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), diphenhydramine, and dopamine antagonists.
Management
simple measures: walking, stretching, massaging affected limbs
treat any iron deficiency
dopamine agonists are first-line treatment (e.g. Pramipexole, ropinirole)
benzodiazepines
gabapentin
RLS - Diagnosis: Example Question
A 35-year-old lady with no significant past medical history presents to you with lethargy and fatigue over several years, often finding she does not sleep well at night. She complains of a sensation of discomfort in her lower extremities at rest, particularly worse when she is trying to fall asleep. She also describes an abnormal crawling and itching sensation below the knees and often walking will relieve her symptoms. There is no history of pain or nigh time snoring. Clinical examination and routine blood investigations are unremarkable. She tells you that over the years her general practitioner has ordered several tests on her that have all been normal, including brain imaging, thyroid function, and monitoring of her haemoglobin levels. She is not on any medications. She is now struggling to do her job as a teacher and is now working only part time because of the symptoms. Considering the likely underlying diagnosis, which of the following would you use to try and alleviate her symptoms?
Lithium Quinine > Pramipexole Amitriptyline Acetazolamide
The diagnosis is restless leg syndrome (RLS). This is a neurologic movement disorder of the limbs that is often associated with a sleep complaint. This will often end up presenting in neurology clinics and it is important to know how to help such patients. RLS can lead to significant physical and emotional disability.
Hemiballism
Occurs following damage to the Subthalamic nucleus
= movement disorder characterised by very violent movements of arms or limbs
BALLISTIC Movements:
- involuntary
- sudden
- jerking
- occur CONTRALATERAL to side of lesion
- primarily affect PROXIMAL limb musculature
- distal muscles may display more choreiform-like movements
- Sx may decrease whilst patient is asleep
NB: Patients can seriously injure themselves!
Caused by stroke or other lesion of subthalamic nucleus
Mx:
- Antidopaminergic agents eg Haloperidol = mainstay of treatment
Chorea
= involuntary rapid jerky movements which often move from one part of the body to another (in contrast to slower sinuous movement of limbs = athetosis)
Chorea = caused by damage to basal ganglia, especially the caudate nucleus
Causes of Chorea
- Hungtingon’s disease
- Wilson’s disease
- Ataxic telangiectasia
- SLE and Antiphospholipid syndrome
- Drugs: COCP, L-Dopa, Antipsychotics
- Neuroacanthytosis
- Pregnancy - Chorea Gravidarum
- Thyrotoxicosis
- Polycythaemia rubra vera
- Carbon monoxide poisoning
- Cerebrovascular disease
Movement Disorders in order of least speed to fastest speed
DYSTONIA - Fixed position (e.g. Metaclopramide in Young F)
ATHETOSIS - Snake-like writhing (slow)
CHOREIFORM - Like a dance choreographer
BALLISTIC/BALLISMUS/HEMIBALLISMUS - FAST flinging movements, patients can injure themselves or others
Akathisia
Restlessness of arms and legs
Common SE of anti-psychotics
Opisthotonus
Describes a state of Hyperextension and Spasticity in which a patient’s neck and spinal column enter into an arching position
= An extra-pyramidal effect
Caused by spasm of axial muscles
Assoc with TETANUS
APHONIA
Describes inability to speak
Causes:
- recurrent laryngeal nerve palsy (eg Post Thyroidectomy)
- Psychogenic - a form of conversion disorder
Oculogyric Crisis
= Dystonic reaction to drugs, in particular Neuroleptics and Dopaminergic medications (classically Metoclopramide and Haloperidol)
- Characterised by a prolonged involuntary upward deviation (Bilateral elevation of the visual gaze) of the eyes
Causes:
- Phenothiazines
- Haloperidol
- Metoclopramide
- Postencephalitic Parkinsons Disease
Mx: IV BENZTROPINE/Procyclidine
(IV Anti-muscarinic)
