First described in 1877 as the appearance of psoriatic lesions in the uninvolved 
skin of psoriatic patients as a consequence of trauma, the Koebner phenomenon 
has since been described in numerous diseases. Other authors have tried to 
implicate either infections or parasitic causes as the pathogenesis of this 
phenomenon. Subsequent research by many authors have contributed to our poor 
understanding of this reaction in the hope of understanding the pathogensis of 
psoriasis. We present a review of the literature covering the following topics 
as they relate to the Koebner phenomenon: diseases that koebnerize and their 
possible causes, predisposing and provoking factors, type, site, depth and 
degree of trauma, the all or none phenomenon, time lag, site preference, 
medications, inhibition of koebnerization and reverse koebnerization.