Dynamic Mechanical Allodynia--One Clinical Sign, Several Mechanisms: Five Illustrative Cases.

Pain evoked by tangential movement across the skin is usually defined as dynamic mechanical allodynia (DMA). Some patients complain of DMA as troublesome as spontaneous pain and refer a marked interfering with activities of daily living and sleep. Pathophysiology of DMA is complex and can be related to several mechanisms, both nociceptive and neuropathic. Five exemplificative clinical cases of DMA are presented, each associated to a possible specific mechanism: injured skin DMA, peri-injured skin DMA, far injury DMA, nerve-confined DMA and fear DMA (pseudo allodynia). The identification of these subcategories of DMA can stimulate further studies aimed at evaluating the usefulness of a mechanism-based therapy for the different clinical forms of DMA.