What else can cause burning and tingling down the arms? i've had a neg brain, cervical, low, and middle back mri done. autoimmune blood tests are still out.

Need to examine: It is not feasible to provide a meaningful opinion without taking additional history, physical examination and may be some tests. It would be prudent to see your doctor and discuss if you may be depressed. Counter-intuitive as it may seem, exercise may help. Start with low intensity exercise such as walking and gradually increase the intensity as tolerated. Wish you good health!

Burning and tingling: There are two general reasons for this. Vascular issues or nerve issues. Often missed in the diagnosis of thoracic outlet syndrome, which requires a good examination. Has someone considered your circulation?