Cerebral palsy can be classified into four types: spastic, athetoid, ataxic and mixed. Spastic cerebral palsy is the most common form, accounting for between 70 and 80 percent of all cerebral palsy cases. Limb muscles are stiff and remain permanently contracted. This form of cerebral palsy is further subdivided depending on which limbs are affected. Both legs may be affected, turning in and crossing at the knees. This is called spastic diplegia, characterized by the 'scissors' gait. Another type of spastic cerebral palsy is spastic hemi paresis or weakness of muscles in one half of the body. Uncontrollable shaking or tremors often accompany this type of spasticity. If the tremors are severe, movement can become very difficult. Athetoid or dyskinetic cerebral palsy affects 10 to 20 percent of all cerebral palsy patients, and is characterized by slow, writhing movements. Such movements are uncontrollable and usually occur in the hands, feet, arms and legs. Face or tongue muscles may also be affected, resulting in drooling or grimacing. If tongue muscles are affected, patients may have difficulty speaking. Athetoid cerebral palsy typically becomes worse during stress, and writhing movements in affected body parts disappear during sleep. Ataxic cerebral palsy affects between five and ten percent of all cerebral palsy patients. This form of cerebral palsy is characterized by deficits in sense of balance and depth perception. These result in poor coordination, particularly with fine motor tasks, and a wide-based, awkward gait. People with ataxic cerebral palsy may also have an intention tremor, which is a tremor that occurs when attempting a voluntary movement such as picking up an object. Mixed cerebral palsy affects up to 30 percent of all cerebral palsy patients. In these patients, symptoms of more than one of the three main types of cerebral palsy described above may be present. Most commonly, spastic and athetoid forms of cerebral palsy coexist. |
