[Detection of the Köbner phenomenon of the skeleton of patients with psoriasis].

Psoriasis is a humorally controlled systemic disease. The degree of "eruptive strength" of manifestation results from hereditary factors (disposition) and environmental factors (provocation). We were able to demonstrate that the well-known Köbner phenomenon of the skin also occurs on the skeleton of patients suffering from psoriasis. We analysed 83 patients in whom bone scans were carried out. Our results indicate that provocation factors such as bacterial foci and/or trauma correlate with a significantly higher number of pathological scintigraphic findings, ranging up to "hot spots". Furthermore, not only did bone fractures remained scintigraphically positive for an unusually long time, traumas of the end phalanx could be demonstrated in 70% of psoriatic patients compared with 21% of a control group. Obviously, one factor alone or a combination of factors triggers the involvement of the skeleton as a "deep Köbner phenomenon". In psoriatic patients the response of bone metabolism to disturbance differs from that of non-psoriatic patients in that there is a long-lasting dysregulation. This explains the high correlation between skin and skeletal manifestation in psoriatics. Therefore the manifestation of psoriatic disease is due not to a single-stranded linear causal interrelation but to a multicausal "network pathogenesis". Bone scintigraphy is the diagnostic method of choice in patients with psoriatic osteoarthropathy and allows an objective evaluation of therapeutic success.