Myofascial pain syndrome is a disorder affecting the fascia or connective tissue (soft tissue) that covers a muscle or muscle group. An injured muscle may form a “trigger point” or a taut fibrous band of collagen. A trigger point is a “knot” felt deep in muscle tissue that causes pain in the muscle and a related limb (so-called referred pain). Many times the muscle becomes spastic, and numbness in the leg or foot may occur. Myofascial pain syndrome can be mistaken for a pinched nerve, but the treatment is different. Spasms in the muscles to the side of the neck and back are strongly related to myofascial pain.