This is the mildest form of child onset SMA. People with Type III will vary greatly. However the prognosis is very good. The person with Type III may show difficulty with walking and/or getting up from a sitting or bent over position & negotiating stairs. Balance can be a problem, causing falls, sometimes assistance in getting up is needed. General muscle weakness has an impact on daily living. An assessment may be helpful to identify where the person needs additional aids or adaptations to enable them to live as independently as possible. Children with SMA have enhanced intelligence and usually attend main stream school.
A deficiency of a motor neuron protein called SMN, for survival of motor neurons, resulting from a faulty gene on chromosome 5.
Disease progresses slowly, with walking ability usually maintained until at least adolescence. Wheelchair often required later in life. Life span usually not affected.