I have arm numbness and tingling in my left arm but also sometimes my right arm. My hand also feels like it wants to cripple up. I'm only 26 years old.

Arm numbness. Numbness in the arms often occurs from sleeping with the arms bent or working in a job with a lot of repetition. Other frequent causes include spinal stenosis or compression of the spinal cord. Diabetes, low B12 levels, and low thyroid function are common causes too. A neurological evaluation and a nerve conduction test can identify the cause of the numbness.