Friedreich Ataxia
FRDA is a progressive spinocerebellar disorder typically having prepubertal onset between ages 5 and 15 years, although exceptions occur, with up to 25% having delayed onset into adulthood. Because of…
Gait Disorders—Differential Diagnosis
Muscle. Myopathy is proximally predominant in inflammatory myopathies, steroid myopathy, and Duchenne and limb girdle dystrophies. Waddling gait results from dropping of the pelvis. Patients have difficulty ascending stairs, arising…
Gait Disorders—Differential Diagnosis (Continued)
Basal Ganglia. Extrapyramidal movement disorders affect gait, depending on the interplay of inhibition and disinhibition within the basal ganglia circuitry. Parkinsonian syndromes characteristically have small shuffling steps at initiation of…
Cerebellar Disorders Differential Diagnosis
ACUTE—MINUTES TO HOURS Ischemic stroke and hemorrhage start abruptly. Both worsen clinically over hours if cerebellar edema develops. Note the “posterior fossa mantra” of acute cerebellar and brainstem injury—headache, nausea,…
Cerebellar Cognitive Affective Syndrome
Executive function deficits include problems with working memory, as tested with reverse digit span; mental flexibility is tested using tasks of set shifting; and perseveration is demonstrated using bedside tests…
Cerebrocerebellar Connections
In the cerebral peduncle, prefrontal fibers are most medial, sensorimotor fibers intermediate, and fibers from the parietal, temporal, and occipital lobes are lateral. In the monkey, terminations in the pons…
Cerebellar Motor Examination
Eye Movements. Cerebellar lesions produce unsteady ocular fixation in primary position, microsaccadic oscillations, square wave jerks, ocular flutter, ocular bobbing, and opsoclonus. Pursuit eye movements show saccadic intrusions—jerkiness following a…
Cerebellum Modular Organization
CEREBELLAR CORTICONUCLEAR PROJECTION Output from the cerebellar cortex to the DCN is derived exclusively from PCs and is inhibitory. The vermis projects to the fastigial nucleus, the intermediate cortex project…
Cerebellar Efferent Pathways
The exception to the PC-DCN projection pattern throughout the cerebellum is the vestibulocerebellar cortex (vermal part of lobule IX [uvula], vermal [nodulus], and hemispheric parts [flocculus] of lobule X), which…
Cerebellovestibular Pathways
VESTIBULOCEREBELLAR PROJECTIONS There are five peripheral vestibular end organs; the cristae in the three orthogonally oriented semicircular canals detect movement in the sense of angular rotation in the horizontal, pitch,…
