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From the google images, it seems to be arterial/pressure (i.e. extremely shallow - only the surface skin being missing, no depth to the wound).
I've been trying Comfeel on this and past ones over the years, and it does work, eventually - somehow the Comfeel releases medications which promote skin healing, and the edges of the wound move across to the centre, when it closes. I've got a particularly badly-placed small ulcer on the head of my fibula (which in turn gets rubbed by the hard layer of my socket!), and that IS rapidly closing - another few weeks, and it'll be shut.
This big one behind my calf IS showing signs of closing, but slowly, and it's (as I said) sore.
It's not childbirth, it's not cancer; it just hurts. I will survive. Mrs A is currently in the local cardio unit, and her condition is far more serious.
I'm just using this time when I'm not actively looking after her, in looking after my own dodgy bits instead.
Thanks for allowing me to air this on here.
A