Topical Nitrates for Myofascial Trigger Points

The purpose of this study is to determine whether a topical nitroglycerine patch applied daily over a trapezius trigger point can improve patients' symptoms. If there is improvement, this open label study will help determine the degree of improvement and contribute to the design of a larger double blind placebo controlled trial. We would consider moving forward to a large randomized trial if: * The intervention is acceptable to patients (\>= 70%) and * Compliance is satisfactory (\>=80%) and * We find preliminary evidence of efficacy, i.e. average reduction in pain of 20mm on the VAS.