One of the types of cerebral palsy, which is also the least common form of CP is ataxic cerebral palsy affecting between 5-10 percent of those afflicted by the disease. This type of cerebral palsy is caused by damage to the cerebellum which controls balance and coordination. The cerebellum also coordinates the movement of several groups of muscles. Ataxic cerebral palsy generally affects coordination of movement in an individual’s arms, legs and trunk. It also causes poor muscle tone (not to be confused by muscle strength – although the two conditions can exist together.)

The most common manifestation of ataxic cerebral palsy is intention (action) tremor, especially when carrying out precise movements, like holding a pen or pencil for writing or tying a shoe. This symptom gets progressively worse when attempting a voluntary movement like pressing a button or reaching for an object which will cause the arm and hand to shake. As the hand gets closer to accomplishing the intended task, the trembling intensifies which makes it even more difficult to complete.

While there is no cure for intention tremor in ataxic CP, drug treatments have been found to minimize their effects. Medications like primidone and benzodiazepine, while not recommended for long term use, can alleviate some of the tremor symptoms. Botox which relaxes tightened muscles has been effective in treating voice, hand and head tremors.

A technique publicized in 2005 for treating intention tremor consists of cooling the forearm by wrapping it in a cryomanchet using a circulating fluid. After the treatment most patients experienced reduced tremor for up to half an hour. This practical, albeit short-term treatment can facilitate performing normal daily activities like applying make up, eating, or signing documents. No less important it reduces one’s reliance on caregivers.

Because of their poor sense of balance, people with ataxic CP will walk with their feet unusually far apart (a wide gait). Because of their low muscle tone where the body is constantly trying to counter-balance itself, they tend to look very unsteady.