Differential diagnosis of myofascial pain syndrome and fibromyalgia

This review examines diagnostic factors of myofascial pain syndrome [MPS] a nd fibromyalgia [FMS], and their differential diagnosis, Findings: A base of electrophysiologic and anatomic data exists that suppor ts the clinical identification of myofascial trigger point [TrP] features. Included are electrical characteristics of the TrP, visualization of the ta ut band and strong support for a model of the TrP. The widespread nature of chronic MPS mimics FMS, Fibromyalgia has been found to be associated with a host of clinical and biochemical markers, Objective markers besides wides pread tenderness are needed to distinguish FMS from other conditions. It is not clear if either response to electrical stimulation of the parietal tis sues or the skin rolling test will provide the necessary specificity. Bioch emical markers such as substance P elevation in spinal fluid may be sensiti ve for FMS, but the specificity of the finding is unknown. The possibility is raised that some findings may be related to the severity of chronic wide spread pain, and non-specific. Conclusion: A variety of clinical tests are available to assess both MPS an d FMS, However, tests that are based primarily on the identification of wid espread tenderness will over-diagnose FM, and under-diagnose MPS, and may m iss other causes of chronic myalgia.