Apr 1, 2021 Most of us have been dutifully wearing our face masks for months, and while lots of folks don’t like them, it turns out, for some they are a literal pain in the neck. According to the American Chiropractic Association, side effects of wearing masks for a prolonged period of time could include neck stiffness, as well as upper back pain, jaw pain, headaches and more. The ACA says the neck pain is a result of masks limiting “the lower field of vision,” causing folks, especially those wearing al ill-fitting mask, to “tuck in their chins, shift their body position and hold their necks and posture stiffly to maintain a line of sight.”