MUSCLE DETERIORATION

My uncle has lost movement of his left arm it has proceeded to his right arm.  
and now its going to his legs.  We have been to so many Dr's in San Diego and no one
seems to know what is wrong with him?  We are desperate and do not know what else to do
he has been a guinea pig for this past year and no one is able to give us a reason to why he
is loosing mobility in his arms and soon his legs. He is an active great human being and we
need help. It is sad when you see such an active adult not even be able to pick up a fork.  
Can anyone please help us???  PLEASE!!!!