Spastic Cerebral Palsy

The most common subtype of cerebral palsy, characterised by stiff or tight muscles (hypertonia) and exaggerated reflexes, caused by damage to the motor cortex or corticospinal tracts of the developing brain. Subtypes are further classified by the limbs affected (diplegia, hemiplegia, quadriplegia). For accessibility, spastic CP typically produces jerky or poorly controlled movements, difficulty with fine motor tasks, reduced range of motion, and fatigue, all of which make small-target touch, precise pointing, rapid sequences, and fine gestures problematic. Interfaces with large targets, forgiving timing, sustained contact (rest-and-stroke) rather than tap-and-lift, and switch or voice alternatives are generally more usable.