Primary Lateral Sclerosis
type: Class
subclass of: RKBlQ2mgZn3CTwBfUYIM7s
definition: Primary lateral sclerosis (PLS) is a rare neurodegenerative disorder characterized by the gradual degeneration of upper motor neurons in the brain and spinal cord. This condition leads to progressive muscle stiffness, spasticity, and weakness, primarily affecting voluntary movements while sparing lower motor neurons.