Dry needling works by stimulating the normal healing process of muscles and surrounding tissues by inserting sterile needles into the muscle to relieve pain. This increases blood flow and brings essential nutrients into the muscle tissue, helping to release the knot and allow the muscle to relax completely. It also helps to accelerate healing. It is called dry needling because there is no fluid injected into the muscle. Muscles become knotted when they are overworked or held in a position that does not allow them to relax. This means the muscle is held in a contracted position, which creates an area of irritable muscle. Muscle knots cause pain and also impair how well the muscle can work. Dry needling is useful in reducing pain and improving movement in most conditions.