這段主要是簡介Hypokinetic, Hyperkinetics movements 簡單定義，在病史詢問上需要注意的事項、Functional Movement會有的特色，Periodic movement disorder、以及好用的一些DDx。
1. Classification & Phenomenology
A. Hypokinetic Movement Disorders (BRT)
- Hypokinesia:
- Akinesia: Paucity or absence of spontaneous movement.
- Bradykinesia: Slowness of movement with progressive reduction in speed and amplitude during repetitive actions.
- Parkinsonism:
- Diagnostic Criteria (TRAP Framework):$\ge 2/6$ features, and must include either Rest Tremor (#1) or Bradykinesia (#2):
- Rest tremor
- Bradykinesia
- Rigidity (cogwheel or lead-pipe resistance)
- Loss of postural reflexes (abnormal pull test)
- Flexed posture
- Freezing (motor blocks during gait initiation or turning)
- Diagnostic Criteria (TRAP Framework):$\ge 2/6$ features, and must include either Rest Tremor (#1) or Bradykinesia (#2):
B. Hyperkinetic Movement Disorders (ABCDMTT)
- Athetosis
- Slow, writhing, continuous, involuntary movements primarily involving distal limbs
- Ballism
- Rapid, non-patterned, high-amplitude, violent flinging/throwing movements predominantly affecting proximal limb musculature.
- Chorea:
- Irregular, unpredictable, brief, jerky movements flowing randomly across different anatomical regions. e.g. Parakinesia, Milkmaid grip, Fly-catcher’s / Jack-in-the-box tongue
- Dystonia:
- Sustained or intermittent muscle contractions causing twisting, repetitive movements, or abnormal postures.
- Patterned, Overflow phenomenon, Mirror dystonia, Sensory trick (Geste antagoniste), Task-specific (e.g., writer’s cramp, musician’s dystonia), Null point, State-dependent (Modulated by emotional arousal, fatigue, or relaxation)
- Myoclonus:
- Sudden, brief, shock-like involuntary jerks.
- Positive and Negative myoclonus
- Tremor:
- Involuntary, rhythmic, oscillatory movements produced by alternating or synchronous contractions of agonist and antagonist muscles.
- Tics:
- Brief, intermittent, repetitive, stereotypic movements (motor tics) or sounds (phonic tics); categorized as simple or complex, and clonic/jerky or tonic.
- Iinner premonitory urge and temporarily suppressible by voluntary effort.
C. Functional Movement Disorders 特色
- Suggestibility
Modulation of symptoms following verbal or non-verbal suggestion. - Entrainability
Shift of tremor frequency to match the external pacing - Distractability
Reduction or cessation of abnormal movements during complex tasks. - Inconsistency & Fluctuation
High variability in frequency, amplitude, and anatomical distribution over time. - Mixed / Non-Anatomical Phenotypes
Phenomenologies incongruent with established neuroanatomical pathways.
D. Episodic Movement Disorders
- Paroxysmal Dyskinesias (Dystonia / Chorea Predominant):
- PKD (Paroxysmal Kinesigenic Dyskinesia) PRRT2
- PNKD (Paroxysmal Non-Kinesigenic Dyskinesia) PNKD / MR-1
- PED (Paroxysmal Exercise-Induced Dyskinesia) SLC2A1 (GLUT1)
- Paroxysmal Ataxias (Ataxia Predominant):
- EA1 (Episodic Ataxia Type 1) KCNA1
- EA2 (Episodic Ataxia Type 2) CACNA1A
- Peripheral & Muscle Channelopathies:
- Periodic Paralysis Hypo/ HyperK PP (CACNA1S, SCN4A).
- Neuromyotonia (Isaacs Syndrome) anti-CASPR2/VGKC
2. 好用的 Differential Diagnosis
| Category | Key Conditions & Diagnostic Markers |
| Infectious & Post-Infectious | HIV, Syphilis, SSPE (Subacute Sclerosing Panencephalitis), CJD (Creutzfeldt-Jakob Disease), PML (Progressive Multifocal Leukoencephalopathy), Japanese Encephalitis (bilateral thalamic and basal ganglia predilection) |
| Acquired & Autoimmune / Paraneoplastic | Paraneoplastic Movement Syndromes: Anti-Hu, Anti-Ri, Anti-CRMP5/CV2, Anti-NMDA receptor encephalitis, Anti-GAD65 |
| Monogenic Inherited Disorders | Wilson’s Disease (WD):ATP7B Huntington’s Disease (HD):HTT CAG repeat expansion Neurodegeneration with Brain Iron Accumulation (NBIA):PANK2 (PKAN), PLA2G6 (PLAN) |
