Prevalence
In the industrialized world, the incidence of overall cerebral palsy, which includes but is not limited to spastic diplegia, is about 2 per 1000 live births. Thus far, there is no known study recording the incidence of CP in the overall nonindustrialized world. Therefore, it is safe to assume that not all spastic CP individuals are known to science and medicine, especially in areas of the world where healthcare systems are less advanced. Many such individuals may simply live out their lives in their local communities without any medical or orthopedic oversight at all, or with extremely minimal such treatment, so that they are never able to be incorporated into any empirical data that orthopedic surgeons or neurosurgeons might seek to collect. It is shocking to note that—as with people with physical disability overall—some may even find themselves in situations of institutionalization, and thus barely see the outside world at all. From what is known, the incidence of spastic diplegia is higher in males than in females; the Surveillance of Cerebral Palsy in Europe (SCPE), for example, reports a M:F ratio of 1.33:1. Variances in reported rates of incidence across different geographical areas in industrialized countries are thought to be caused primarily by discrepancies in the criteria used for inclusion and exclusion. When such discrepancies are taken into account in comparing two or more registers of patients with cerebral palsy and also the extent to which children with mild cerebral palsy are included, the incidence rates still converge toward the average rate of 2:1000.
Above the hips, persons with spastic diplegia typically retain normal or near-normal muscle tone and range of motion, though some lesser spasticity may also affect the upper body, such as the trunk and arms, depending on the severity of the condition in the individual (the spasticity condition affecting the whole body equally, rather than just the legs, is spastic quadriplegia, a slightly different classification). In addition, because leg tightness often leads to instability in ambulation, extra muscle tension usually develops in the shoulders, chest, and arms due to compensatory stabilisation movements, regardless of the fact that the upper body itself is not directly affected by the condition. Social implications
Although the term "spastic" technically describes the attribute of spasticity in spastic cerebral palsy and was originally an acceptable and common term to use in both self-description and in description by others, it has since gained more notoriety as a pejorative, in particular when used in pop culture to insult non-disabled people when they seem overly anxious or unskilled in sports (see also the article Spastic (word)). In 1952, a UK charitable organization with a membership mainly of those with spastic CP was formed; this organization called itself The Spastics Society. However, the charity changed its name to Scope in 1994 due to the term spastics having become enough of a pejorative to warrant the name change.Spastic diplegias social implications tend to vary with the intensity of the condition in the individual.