Hehe, I was also going for a picture of some auto-amputation.
I like your sketch, but wonder how you are going to make it look like this is deliberate behaviour rather than, say, a gardening accident?
I think the man’s expression will be key (deliberate not distracted?) but you could also maybe use other visual cues, like already healed finger stumps of various lengths? Also perhaps have him using the secateurs in an obviously not garden-like environment.









