4. Myofascial pain syndromes - second most common cause of chronic pain. These conditions include: myositis, fibrositis, myalgia, muscle strain, injury to the muscle and fascia The pain is a result of muscle spasm, tenderness and stiffness
4. Myofascial pain syndromes - second most common cause of chronic pain. These conditions include: myositis, fibrositis, myalgia, muscle strain, injury to the muscle and fascia The pain is a result of muscle spasm, tenderness and stiffness