I think I commented on this on another thread - a single B vitamin is very unusual and is more likely to affect folic acid or B12. It may be worth having vitamin levels and iron levels tested. Zinc deficiency can also cause poor wound healing and sore skin. Iron deficiency can cause cracks at the corners of the mouth.
I guess it could also be an allergic dermatitis, especially if it was there before the op. I think I would ask to see a dermatologist. But as I mentioned before, reserves of zinc are depleted by the need to repair, so taking some zinc may help. I would also consider taking flax seed oil, especially if you have any dry skin elsewhere.
New stuff: GERD, Recurrent cystitis/Overactive bladder
Lifelong stuff: Food allergies/intolerance, eczema, asthma