Outcome measures: Primary outcome is the change of pain perception from baseline (1 minute before debridement) to time point of maximum debridement/wound profoundness (up to 10 minutes after start of debridement) as measured by the visual analogue scale (VAS). Secondary outcomes are change of pain perception from time point of maximum debridement/wound profoundness to 5 minutes after debridement as measured by the visual analogue scale (VAS), duration of treatment session, duration of debridement, achievement of treatment goal (completion), subjective general perception of analgesia quality during debridement (patient comfort). Baseline characteristics are gender, age, ulcer etiology, time passed between initial ulcer diagnosis and first debridement, wound emergence in terms of suspected trigger for ulcer development, and wound size.