Examination of the Cerebellar System Flashcards
Located behind the dorsal aspect of pons and medulla
Cerebellum
Separated from occipital lobe by tentorium
Cerebellum
Midline portion of the cerebellum also separates two lateral lobes or hemispheres
Vermis
Narrow, ridge-like folds, oriented transversely on
external surface, adjacent to 4thventricle
Folia
Functions of the cerebellum
- Coordinate skilled voluntary movements
2. Receive collateral input from sensory and special sensory systems
T or F:
Cerebellum processes sensory information
True
T or F:
Does not influence motor neurons directly
True
Related to a depression of gamma and alpha motor neuron activity
Hypotonia
“Cerebellar sign par excellence”
Ataxia or dystaxia
Lack of synergy of the various muscle components in performing more complex movements so that movements are disjointed and clumsy and broken up into isolated successive parts
Asynergia
Abnormalities in the rate, range and force of movement
Dysmetria
Abnormality in the rhythm of rapid alternating movements
Adiodochokinesis or dysdiadochokinesis
Variable intonation (prosody) and abnormalities in articulation; described also as staccato, explosive, hesitant, slow altered accent, and garbled speech
Scanning dysarthria
Lesions of the uvula, nodulus produces what kind of nystagmus?
Periodic alternating nystagmus
Posterior midline lesions produces what kind of lesion?
Downbeat nystagmus
Overshooting the target
Hypermetria
A rhythmic tremor of the head or upper trunk (three to four per second)
Titubation
Wide-based stance with increased trunk sway, irregular stepping with a tendency to stagger as if intoxicated
Disorders of Equilibrium and Gait
Incoordination of ipsilateral appendicular movements
Usual etiologies: Infarcts, neoplasms, abscesses
Hemispheric syndrome
A wide-based stance and titubating gait
Ataxia of gait, with proportionally little ataxia on the heel-to-shin maneuver with the patient lying down
Rostral vermis syndrome
Axial disequilibrium (truncal ataxia) and staggering gait
Little or no limb ataxia
Sometimes spontaneous nystagmus and rotated postures of the head
Caudal vermis syndrome
Bilateral signs of cerebellar dysfunction affecting the trunk, limbs, and cranial musculature
Pancerebellar syndrome
Ask the patient to extend the arms straight out front
Do the finger to nose test.
Rapid pronation-supination test, thigh-slapping test
Clinical tests for arm dystaxia
Heel-to-shin test
Heel-tapping test
Clinical tests for leg dystaxia
Observe the patient’s stance
Ask the patient to walk
Tandem-walk
Clinical tests for dystaxia of station and gait
Occurs usually from ethanol or drug intoxication
Pancerebellar syndrome
