Not precisely my field (RES-can knows far more about medical insurance -- I've sent a pm). Has this to do with the German Diagnosis-related Groups (G-DRG) which include the Operationen- und Prozedurenschlüssel (OPS) in calculations for coding? The G-DRG is far more complex than many other DRG systems.
How about procedure category?
=> “These groupings are given as procedure categories, e.g. knee joint replacement, hernia repair, etc.”
@#1: You do indeed appear to be struggling. Leaving aside the monobrow removal or implanting a funny bone, which I presume is intended to amuse, Krankheiten might be better rendered as ‘medical condition’ and Risikokonstellation implies more than the single risk factor you mentioned (twice) => risk factors. See above for Kniegelenkersatz, Verschluss eines Leistenbruchs.
Treatment is then billed at a flat/fixed rate per case.