Spastic diplegia


 * "Little's disease" redirects here.

Spastic diplegia, historically known as Little's Disease, is a form of cerebral palsy (CP) that is a neuromuscular condition of hypertonia and spasticity in the muscles of the lower extremities of the human body, usually those of the legs, hips and pelvis. Doctor William John Little's first recorded encounter with cerebral palsy is reported to have been among children who displayed signs of spastic diplegia.

This condition is by far the most common type of CP, occurring in almost 70% of all cases.

Background
Spastic diplegia's particular type of brain damage inhibits the proper development of upper motor neuron function, impacting the motor cortex, the basal ganglia and the corticospinal tract. Nerve receptors in the spine leading to affected muscles become unable to properly absorb gamma amino butyric acid, the amino acid that regulates muscle tone. Without GABA absorption to those particular nerve rootlets, affected nerves perpetually fire the message for their corresponding muscles to rigidly contract, and the muscles become permanently hypertonic.

This abnormally high muscle tone creates difficulty with voluntary and passive movement, and generally creates stress over time — depending on the severity of the condition in the individual, the constant spasticity ultimately produces pain, muscle/joint breakdown including tendinitis and arthritis, premature physical exhaustion (i.e., becoming physically exhausted even when you internally know that you have more energy than you are able to use), contractures, spasms, and progressively worse deformities misalignments of bone structure around areas of the tightened musculature as the years progress.

Officially, CP is not a progressive condition, and indeed it does not clinically "get worse" given that the nerves, damaged permanently at birth, neither recover nor degrade. This aspect is especially significant because other neuromuscular conditions with similar surface characteristics, like many forms of multiple sclerosis, indeed do degrade the body over time and do involve actual progressive worsening of the condition. However, in the case of spastic CP, the lack of progression of the condition itself is irrelevant, because the symptoms experienced cause compounded effects on the body that are typically just as stressful on the human body as a progressive condition is. But even though muscle tightness is the symptom and not the cause, symptoms are typically seen as the primary area of focus for treatment, except when a rhizotomy is brought into consideration.

Like nearly all forms of CP, and unlike any other condition that may present with similar effects, spastic diplegia is entirely congenital in origin — that is, it is acquired shortly before or during a baby's birth process. Things like exposure to toxins, traumatic brain injury, encephalitis, meningitis, drowning or suffocation do not tend to lead to spastic diplegia in particular or even cerebral palsy generally. Overall, the most common cause of spastic diplegia is Periventricular leukomalacia, more commonly known as neonatal asphyxia (a sudden in-womb shortage of oxygen-delivery through the umbilical cord), combined with premature birth, which even by itself runs a risk of the infant developing some type of CP. Additionally, though, circumstances such as Hypoxia of the brain, hematoma in the brain or other birth trauma, or, also, the presence of certain maternal infections during pregnancy such as congenital rubella syndrome, can all lead to spastic diplegia, whether on their own or in some combination of one another.

Presentation
Individuals with spastic diplegia are very tight and stiff and must work very hard to successfully resist and "push through" the extra tightness they perpetually experience. Other than this, though, these CP-affected individuals are almost always normal in every significant clinical sense. When they are younger, spastic diplegic individuals typically undergo gait analysis so that their clinicians can determine the best assistive devices for them, if any are necessary, such as a walker or crutches. The main difference between spastic diplegia and a normal gait pattern is its signature "Scissor gait" — a style that some able-bodied people might tend to confuse with the effects of drunkenness, multiple sclerosis or another nerve disease. The degree of spasticity in spastic diplegia (and, for that matter, other types of spastic CP) varies widely from person to person. No two people with spastic diplegia are exactly alike. Balance problems and/or stiffness in gait can range from barely noticeable all the way to misalignments so pronounced that the person needs crutches or cane to assist in ambulation. Less often, spasticity is severe enough to compel the person to use a wheelchair; in general, however, lower-extremity spasticity in spastic diplegia is rarely so great as to totally prevent ambulation — most people with the condition can walk.

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. Additionally, because leg tightness often leads to instability in ambulation, extra muscle tension usually develops in the upper body, shoulders, and arms due to compensatory stabilization movements, regardless of the fact that the upper body itself is not directly affected by the condition.

Treatment
As a matter of everyday maintenance, muscle stretching, range of motion exercises, yoga, contact improvisation, modern dance, resistance training, and other physical activity regimens are often utilized by those with spastic CP to help prevent contractures and reduce the severity of symptoms.

Major clinical treatments for spastic diplegia are:


 * Baclofen (and its derivatives), a gamma amino butyric acid substitute injected into the spinal fluid for trial, and thereafter administered either orally or via an intrathecal pump;
 * Phenol, injected selectively into the over-firing nerves in the legs on the muscle end to reduce spasticity in their corresponding muscles;
 * Botox, injected directly into the spastic muscles;
 * orthopedic surgery to release the spastic muscles from their hypertonic state, a usually temporary result because of the source of the spasticity being in the nerves, not the muscles; and,
 * Selective Dorsal Rhizotomy, a neurosurgery directly targeting and eliminating ("cutting" or "lesioning") the over-firing nerve rootlets and leaving the properly-firing ones intact, thereby permanently eliminating the spasticity but compelling the person to spend months re-strengthening muscles that will have been severely weakened by the loss of the spasticity.

Social implications
Socially, it should be noted that 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, particularly when used in pop culture to insult able-bodied people when they seem overly anxious or unskilled in sports (see also the article spazz).

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 spastic having become enough of a pejorative to warrant the name change.

Spastic diplegia's social implications tend to vary with the intensity of the condition in the individual. If its effects are severely disabling, resulting in very little physical activity for the person, social elements can also suffer. Workplace environments can also be limited, since most labor-intensive work requires basic physical agility that spastic diplegics may not possess. However, the degree of variability among individuals with spastic diplegia means that no greater or lesser degree of stigma or real-world limitation is standard. Lesser effects usually mean fewer physical limitations, better-quality exercise and more real-world flexibility, but the person is still generally seen as different than the norm. How such a person chooses to react to outside opinion is of paramount importance when social factors are considered.

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.

The incidence is higher in males than in females; the Surveillance of Cerebral Palsy in Europe (SCPE) reports a M:F ratio of 1.33:1. Variances in reported rates of incidence across different geographical areas in industrialised 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.

In the United States, approximately 10,000 infants and babies are born with CP each year, and 1200–1500 are diagnosed at preschool age when symptoms become more obvious. Interestingly, those with extremely mild spastic CP may not even be aware of their condition until much later in life: internet chat forums have recorded men and women as old as 30 who were diagnosed only recently with their spastic CP.

Overall, advances in care of pregnant mothers and their babies has not resulted in a noticeable decrease in CP. Medical advances in areas related to the care of premature babies results in a greater survival rate. Only the introduction of quality medical care to locations with less-than-adequate medical care has shown any decreases. The incidence of CP increases with premature or very low-weight babies regardless of the quality of care.