What type of disorder is Huntington’s dz?
Autosomal-Dominant
Trinucleotide repeat – CAG
Chromosome 4
When does the expansion of CAG repeats occur in Huntington’s?
Spermatogenesis
What is the cause of neuronal death in Huntington’s?
NMDA-R binding & Glutamate toxicity
What changes can be seen on imaging of Huntington’s?
Atrophy of Striatal Nuclei
- Main inhibitors of movement
What is the mnemonic for remembering Huntington’s Disease
CAG trinucleotide repeat:
“Caudate loses Ach & Gaba”
Movement Disorder: Hemiballismus
- Presentation:
- Lesion:
- Notes:
Movement Disorder: Hemiballismus
- Presentation:
- Sudden, wild flailing of 1 arm +/- ipsilateral leg
- Lesion:
- Contralateral Subtahalmic nucleus (e.g., lacunar stroke)
- Notes
- Half-of-body ballistic” (contralateral lesion)
Movement Disorder: Chorea
- Presentation:
- Lesion:
- Notes:
Movement Disorder: Chorea
- Presentation:
- Sudden, Jerky, Purposelsess movements
- Lesion:
- Basal ganglia (e.g., Huntington’s)
- Notes
- Chorea = dancing
Movement Disorder: Athetosis
- Presentation:
- Lesion:
- Notes:
Movement Disorder: Athetosis
- Presentation:
- Slow, Writhing movements; especially seen in FINGERS
- Lesion:
- Basal Ganglia (e.g., Huntington’s)
- Notes:
- Writhing, snake-like movements
Movement Disorder: Myoclonus
- Presentation:
- Notes:
Movement Disorder: Myoclonus
- Presentation:
- Sudden, brief, uncontrolled muscle contraction
- Notes:
- Jerks; hiccups; common in METABOLIC abnormalities as Renal and Liver failure
Movement Disorder: Dystonia
- Presentation:
- Notes:
Movement Disorder: Dystonia
- Presentation:
- Sustained, involuntary muscle contractions
- Notes:
- Writer’s cramp; blepharospasm (sustained eyelid twitch)
Movement Disorder: Essential Tremor
- Presentation:
- Notes:
Movement Disorder: Essential Tremor
- Presentation:
- Action tremor; exacerbated by holding posture/limb position
- Notes:
- Genetic predisposition
- Patients often self-medicate w/ EtOH
- Tx: beta-blockers, primidone
Movement Disorder: Resting Tremor
- Presentation:
- Lesion:
- Notes:
Movement Disorder: Resting Tremor
- Presentation:
- Uncontrolld movement of distal appendages (hands most noticeable)
- Tremor alleviated by intentional movement
- Lesion:
- Parkinson’s disease
- Notes:
- Occurs at rest
- “Pill-rolling tremor” of Parkinson’s
Movement Disorder: Intention Tremor
- Presentation:
- Lesion:
Movement Disorder: Intention Tremor
- Presentation:
- Slow, zig-zag motion when pointing/extending toward a target
- Lesion:
- Cerebellar dysfunction
