Muscle knots in the Lateral Pterygoid muscle are located very deeply within your face, near the hinge of your jaw joint, making them nearly impossible to feel directly from the outside. These muscle knots can refer pain to the jaw joint, ear, temple, cheek, and even upper teeth, often mimicking TMJ dysfunction, sinus pressure, or tension headaches. People commonly experience clicking, popping, or locking of the jaw, especially during chewing, talking, or stressful situations like teeth grinding.