Functional Dry Needling can be used to target and treat trigger points in almost any muscle of the body. The benefits are a decrease in pain, improved tissue extensibility (flexibility), and improved function (i.e. getting you back to doing what you want to do most).
Check out the video for a brief explanation of Functional Dry Needling plus see how I would use it to treat the upper trapezius muscle. This muscle can be a contributor to neck and shoulder pain as well as headaches, but responds very well to the technique.