INVOLUNTARY MOVEMENTS Resting tremors: associated with parkinsonism (bradykinesia PLUS rigidity or tremor) (Extrapyramidal) Basal ganglia circuitry: modulates and enhances Parkinson’s disease: bradykinesia + hypokinesia + low-frequency voluntary movement “pill-rolling” tremor + cogwheel rigidity • Pathways enter through striatum and exit through thalamus • Other signs: masked facies, stooped posture, shuffling gait & ● Direct (excitatory) pathway involves D1 receptors en bloc turns, decrement in repetitive movements (finger ● Indirect (inhibitory) pathway involves D2 receptors tapping) • Postural instability appears later in course, seen on pull test Framework for involuntary/abnormal movements: • Non-motor: cognitive complaints, mood disorders, REM sleep 1) Characterize the abnormal movement – descriptors include: disorders, autonomic dysfunction, anosmia a. Hyperkinetic vs. hypokinetic • Diagnosis is clinical – DaT scan is helpful if unsure b. Rhythmic vs. arrhythmic • Treatment: dopaminergic meds (e.g., Sinemet); DBS for c. Degree of voluntariness refractory cases d. Stereotypic vs. non-stereotypic e. Character (e.g., jerky vs. oscillatory vs. flowing, etc.) Parkinson-plus syndromes 2) Determine the phenomenology, followed by the syndrome • Multiple system atrophy: MSA-C (cerebellar) and MSA-P associated with the phenomenology (parkinsonism; extreme autonomic dysfunction) variants • Corticobasal degeneration: parkinsonism plus cortical signs TREMOR: hyperkinetic, rhythmic, oscillatory, bidirectional; (language dysfunction, apraxia, alien-limb phenomenon) characterized by alternating/synchronous activity of agonistic and • Progressive supranuclear palsy: parkinsonism plus eye antagonistic muscles movement abnormalities and profound postural instability Action (including kinetic, postural, & isometric) tremors • Essential tremor: chronic, progressive, medium-frequency CHOREA: hyperkinetic, arrhythmic, non-stereotyped, flowing tremor – usually in the hands and arms bilaterally movements o May progress to head/voice, ± cerebellar signs and • Part of a choreiform spectrum, along with: intention tremor later in disease course o Athethosis = slower flowing movement o Family history is frequently positive for ET o Ballismus = large amplitude flinging movement o Test with spiral-drawing – tremor worsens on an axis • Etiologies include Huntington’s disease, Sydenham chorea o 1st-line treatment = primidone or propranolol (rheumatic fever), pregnancy, stroke, celiac, APLS, hereditary • Enhanced physiologic tremor: high-frequency, low-amplitude tremor that emerges in certain settings (e.g., stress, Huntington’s disease: cognitive impairment, chorea (choreoathetosis sympathetic stimulation) – usually in the hands/voice and hemiballismus), and psychiatric symptoms o No cerebellar signs or intention tremor • Autosomal dominant trinucleotide repeat (CAG) expansion in o Transient once the underlying cause is reversed huntingtin gene, causing protein aggregates • Cerebellar tremor: low-frequency tremor with intentional • Ocular signs: slow eye movements, increased saccade component (worsens when approaching target) latency o Seen in the setting of any cerebellar pathology • Parkinsonism can appear later in course or in young patients o Associated with other cerebellar signs (eye movement and gait abnormalities, ataxia, dysdiadochokinesia) • Diagnosed with genetic testing – requires genetic counseling • Manage symptoms with dopamine blockade MYOCLONUS: hyperkinetic, arrhythmic, jerky, unidirectional; brief TICS: hyperkinetic, stereotyped, semi-voluntary (can be suppressed contractions or pathologic relaxation of specific muscle groups for short periods, but urge to perform the movement increases) • Positive myoclonus = abnormal contraction • Negative myoclonus = asterixis; pathologic relaxation Tourette syndrome: characterized by both motor and vocal tics, with • Causes include: onset in childhood o Physiologic (e.g., hiccups) • Motor tics include grimacing, shrugging, blinking, head jerking o Toxic-metabolic (e.g., medications, uremia, • Vocal tics include sniffing, throat clearing, other utterances hyperammonemia) • Frequently comorbid with other psychiatric disorders (e.g., o Hypoxic-ischemic brain injury OCD, anxiety) o Epileptic (e.g., JME) • Management: o Genetic o Mild tics can be managed with supportive care/counseling DYSTONIA: hyperkinetic, arrhythmic; sustained muscle contraction o Psychotherapeutic techniques = comprehensive resulting in abnormal posturing and/or twisting behavioral intervention for tics (CBIT), habit reversal • Generalized dystonia: usually idiopathic or genetic/inherited therapy (HRT) • Cervical dystonia: focal dystonia of the neck; torticollis o More bothersome tics can be managed with dopamine • Blepharospasm: focal dystonia of the eyes blockers, alpha agonists (guanfacine, clonidine) • Task-specific dystonia: focal dystonia due to overuse (e.g., musician’s dystonia, dystonic writer’s cramp) • Secondary dystonia due to medications/reactions: seen with Key features of the examination in movement disorder patients: dopamine-blocking medications (e.g., acute dystonic • Movement exam: think on your feet! reaction, tardive dystonia) o Observation – beginning from the moment you encounter the patient! Treatment options for dystonia: o Test for emergence of movements during distraction • Benzodiazepines, muscle relaxants, anticholinergics (e.g., cognitive load) or activity (e.g., spiral drawing) • Consider botulinum toxin injection if focal o Muscle tone and bulk • Consider DBS if genetic o Repetitive movements and tests for ataxia o Gait assessment and pull test • Mental status testing • Extraocular movements, gaze, tracking and saccades • Speech, including clarity and phonation For additional resources/videos, check out Dr. Schaefer’s modules at movementmodules.yale.edu. .