hand and arm numbness causes
Hand numbness is usually caused by damage, irritation or compression of one of the nerves or a branch of one of the nerves in your arm and wrist. Diseases affecting the peripheral nerves, such as diabetes, also can cause numbness, although with diabetes similar symptoms usually occur first in your feet. In very uncommon instances, numbness can be caused by problems in your brain or spinal cord, although in such cases arm or hand weakness or loss of function also occurs. Numbness alone is only rarely associated with potentially life-threatening disorders, such as strokes or tumors.