Definitions (J Child Neurol 2003;18:S1)
• Tics: Sudden, “brief” involuntary (but suppressible), stereotyped mvmts/vocalizations
• Tremor: Involuntary, usually regular, oscillatory mvmts; may be limited to an extremity, may involve entire body including tongue
• Chorea: Hyperkinetic, invol, arrhythmic, nonrepetitive, random jerking mvmt. Typically expressed distally, but may involve entire body or extremities; may flow into a voluntary movement and possess a dancing quality
• Ballism: Violent, involuntary, usually high amplitude flailing mvmt of entire extremity
• Athetosis: Involuntary, alternating flexion/extension, writhing mvmts typically accentuate in distal extremities & perioral muscles; may involve entire body + tongue (not eyes)
• Dystonia: Tonic fixation of posture, not dependent upon contracture (not a mvmt)
• Myoclonus: Involuntary asym brief shock-like w/ recovery, muscle jerk may be limited to distal extr or involve entire body, sym in phase or multifocal and asym
Etiology
• Tics: Tourette syndrome (TS), transient tic of childhood, drug-induced
• Tremor: Hyperthyroid, hypoglycemia, essential tremor, drugs (AEDs, amphetamines, bronchodilators, antidepressants, caffeine, steroids), CP, Wilson dz, juvenile Huntington dz, and multiple other (esp of cerebellar and other central motor system relays and tracts)
• Chorea: Sydenham chorea, CP, drugs (AEDs, antidepressants, antihistamines, OCP, CCBs, digoxin), SLE, Wilson dz, post-pump cardiac surgery. PANDAS
• Ballism: Subthalamic nucleus damage/hemiballismus typically hypertensive small vessel infarct but other small causes of small focal disease rarely
• Athetosis: CP, host of degenerative infectious, metabolic disorders, ischemia, trauma
• Dystonia: Neuroleptic-induced, dopa-responsive dystonia (Segawa), Sandifer syndrome, dystonia musculorum deformans, CP, drugs (AEDs, antipsychotics, antihistamines, CCBs), Wilson dz, perinatal hypoxia, brain tumors, trauma
• Myoclonus: Benign neonatal sleep myoclonus/“sleep starts,” epilepsy, drugs (AEDs, antidepressants), infxns (SSPE, HSV, HIV, Creutzfeldt–Jakob), autoimmune (MS), neoplastic/tumors, paraneoplastic (neuroblastoma), metabolic (most prevalent; renal failure, hyperglycemia), hypoxia