I have had numbness almost constantly in left shoulder and upper arm for close to a year. Approx 6 months ago it also started in the right shoulder and upper arm. Now here about a week ago the left upper arm muscle has starting twitching on and off all day everyday. I have not done anything strenuous recently that would have started the spasms. Also do not know if this is relevant to the above symptoms but nearly all my lymph nodes are enlarged. What could possibly be causing the numbness and spasms