Bondo, or JB Weld comes to mind......
You undoubtedly have a hard callus there that is causing a stress riser. Various softening agents combined with
careful trimming will help.
Be advised that Neosporin has an adverse healing effect in large amounts. While it will prevent infections, if the wound is kept packed with it, it will not heal.
I normally heal quickly. I had a large growth removed from my thigh several years ago that left a deep cauterized wound.
The doctor prescribed Neosporin with a bandage.
I just filled the wound with the stuff every day.
After about a week, it was pink, healthy, and just as open and raw as when he made it.
I called, and when he finally realized what I was doing, he told me just a light film of the stuff.
I did that, and left off the bandage, and it healed over in two days.
You could also try this stuff.
http://astyptodyne1906.com/index.html
I didn't know that they still made it. I used my last about 40 years ago when I almost cut the whole end off my finger in the swamp.
A friend's grandfather poured some on it and wrapped it in a piece of a clean shirt we cut up.
He poured some on every morning, and the large deep cut healed completely with no infection, pain or barely even a scar.
The old time drugstore that carried it in my area closed a few years later, and I could not find it anymore.
But, thanks to this interweb thingy, I have found it again. Great stuff, but you better like the smell, because it will stay with you.
Personally, I like it.