A "muscle knot" is typically an area of tissue that has become inflamed and irritated. Also known as restrictions, trigger points, pressure points, or adhesions, these areas are caused by a variety of factors: - Stress. When you're stressed, you probably have a tendency to clench your jaw, or elevate your shoulders. These prolonged muscular contractions cause your body to build up tension and form these tender areas. Most of the time, you will feel these places (top of th