Introduction to Movement Disorders Flashcards
Definition of movement disorders
Impaired modulation of movement
In spite of maintained generation of movement/strength
Not a problem with upper and lower motor neurons
Almost all movement disorders localize to the basal ganglia
Examples of
1. Hypokinetic
2. Hyperkinetic
disorders
- Parkinsonism
2. Tremor, chorea, dystonia, myoclonus, tics, ataxia
Parkinsonism
Bradykinesia is key feature (decreased amplitude)
Plus one of: tremor, rigidity, and postural instability
Tremor
Involuntary oscillation (rhythmic movement) of a body part, typically about a joint
Due to alternating contraction of reciprocally innervated muscles (agonists/antagonists)
Examples: enhanced physiological tremor, drug induced, essential, parkinsonism, MS
Chorea
Brief, random, flitting movements
Often involving multiple body parts
Examples: HD, stroke, metabolic derangements, autoimmune disorders
Ballism
Large amplitude, flinging movements
From chorea affecting proximal limb muscles
Dystonia
Sustained or intermittent muscle contractions
Causing abnormal and often repetitive movements, postures, or both
Movements are typically patterned and twisting, may be tremulous
Ex: idiopathic, stroke, CP, Parkinson disease, inherited/genetic, Wilson disease
Myoclonus
Brief muscle jerks
Caused by a brief activation of a group of muscles
Can be generated from anywhere along the neural axis
Ex: physiological, metabolic, drug induced, post anoxic brain injury, hemifacial spasm
Tics
Repetitive, purposeful or semi purposeful movements or actions preceded by an urge which is relieved after the movement
Ex: tourettes, drug induced, HD
Ataxia
Incoordination of voluntary movements due to cerebellar dysfunction
Causing an irregularity in timing and/or precision of movements
Look for cerebellar signs!
