bradicinesia

Bradicinesia (also spelled bradykinesia) is a slowing of voluntary movement and a reduced ability to initiate movements. It is a hallmark feature of Parkinsonism and related neurodegenerative disorders, and it often appears with other motor symptoms such as rigidity, tremor, and impaired balance.

Pathophysiology typically involves degeneration of dopaminergic neurons in the substantia nigra pars compacta, leading to decreased dopamine signaling in the striatum. This disrupts the normal balance of the basal ganglia-thalamo-cortical circuits that control movement, resulting in slower movement, reduced amplitude, and difficulty with rapid, successive actions.

Clinically, bradicinesia presents as delayed movement initiation, prolonged time to perform tasks such as finger tapping or rising from a chair, and a decrease in spontaneous movements including facial expression (hypomimia) and arm swing. Patients may also exhibit micrographia (small handwriting) and sometimes freezing of gait, particularly with changes in environment or gait speed. The severity and pattern of bradykinesia can be asymmetric in early disease.

Diagnosis is primarily clinical, based on history and observation of slowed movement. Assessment scales such as the Unified Parkinson's Disease Rating Scale may be used. Brain imaging and specialized tests can support diagnosis in uncertain cases, for example to distinguish Parkinsonism from other conditions, or to confirm dopaminergic deficits with DaT scans.

Management focuses on symptom relief and functional improvement. Pharmacologic options include levodopa-carbidopa, dopamine agonists, and MAO-B inhibitors. Nonpharmacologic approaches such as physical therapy, regular exercise, and occupational therapy are important. In selected cases, deep brain stimulation may be considered. The course of bradicinesia varies with the underlying condition and treatment response.