Bell's palsy, also known as facial palsy, can occur at any age. The exact cause is unknown. It's believed to be the result of swelling and inflammation of the nerve that controls the muscles on one side of your face. Or it might be a reaction that occurs after a viral infection....
jaw, upper back and down the inside of the left arm; it can be triggered by exercise, stress, heavy meal or cold environment and relieved by rest or the oral drug called nitroglycerin.