Koebner Phenomenon

Koebner Phenomenon is described as the appearance of new skin lesions of a previously existing dermatologic condition at the site of local injury (such as sunburn, vaccinations and superficial wounds). The skin conditions that most commonly manifest this phenomenon include psoriasis, lichen planus, vitiligo and halo naevus. The exact cause of this phenomenon is not clear but the current theories point towards a requirement for injury to the epidermis and the dermis at the same point. Non-specific steps such as production of inflammatory mediators and neuropeptides have been suggested to play an initial role towards triggering a secondary disease-specific process. Reference: https://dermnetnz.org/topics/the-koebner-phenomenon/