I have a client who comes for a full leg, bikini and underarm wax once a month and she has psoriasis on her legs. Mainly on her knees and shins and she insists that I wax over them as she said its the only way that keeps it from getting worse. She has had waxing done for the past 20 years and says if the areas are omitted due to a therapist not willing to wax over them, she can guarantee that the psoriasis goes worse until she has her appointment again.
I do use a new spatula for each area and don't double dip on the psoriasis bits. She then apparently gives the areas a 'blast' under the sun lamp once the top scales have been removed with the wax.
She always tips me well and says not many therapists will do this for nowadays and says she is so happy to find me who will still do it for her. She has been coming to me now for the last 6 months and the psoriasis has not got worse in this time.
If the areas were broken I would not wax and I have explained this to her, to which she is happy about. She states it only gets to that stage if its not waxed and zapped lol!!