Overall, spasticity affects about 500,000 people in the United States and more than 12 million people throughout the world. The number of people affected depends upon the cause of the spasticity.
The number of people with MS varies with geographic location (more people living in northern climates have MS), race (MS is more common in Caucasians), socioeconomic status (rates of MS are higher in those with a higher socioeconomic status), and sex (MS is twice as common in women as in men). Of those people with MS, more than 85% have at least mild spasticity, with more than 30% being forced to at least frequently modify their activities because of the spasticity.
Although it is not clear how many children have cerebral palsy, cerebral palsy is estimated to affect 2 to 4 out of every 1,000 children in the world who are between 3 and 10 years old. About 50% of cerebral palsy is related to a specific event in which levels of oxygen to the brain of the child were not adequate.
In the United Kingdom, approximately 100,000 people have a first-time stroke every year, and an additional 30,000 have a repeated stroke. Stoke afflicts almost 2,000 out of every 1 million people per year worldwide. Almost 40% of people who have a stroke continue to have spasticity one year later.