Hello. My father asked me to look at his symptoms online. He s painting and within 5 minutes his arm starts to burn near his bicep and then they go numb. If he rests his arms, they start to throb uncomfortably, including his joints - shoulders, elbows, wrists and fingers. Do you have an idea of what would be causing this? He is mostly concerned about diabetes (my paternal grandfather has diabetes) but was wondering if it was something else as well.