<s>[INST] I am constantly having a chronic dull pain in my upper left arm for 3 days. I went to the ER and they took blood test, chest x-Ray, sonogram of my arm, and an EKG. They gave me an intravenous pain killer and a pill for muscle relaxant. All test came back normal. They think it is rheumatoid, not sure. If i sit up with my neck down, I don t feel pain, but it I raise my neck I feel the pain. What do you think it is? I am taking muscle relaxant and Percocet. It is a temporary relief. [/INST] Hi,   I understand your query.   After reading you query, I feel it to be related to cervical spine/ cervical rib. Please get Xray of your cervical spine.    Consult an orthopedic doctor .   I feel muscle relaxants, physiotherapy should give you satisfactory results.   Thanks. </s>