Patches on ca'ts back legs on the heel

My cat Nero is 2 years old and all black, I recently noticed a orangeish brown colored scab when i picked at it. he didn't like me messing with it (he doesn't like his back feet messed with as much) There wasn't any blood or anything, just super dry skin. I'm not sure if i want to go to my vet or not if i can help it. I've heard of cases saying it's ringworm however he is always inside and i stay up on his vaccinations. Please help! The large bald patch shown is only on the one leg. 

Indoor pets that are vaccinated can easily get ringworm, which can quickly spread to humans and other pets. A vet needs to take a look at that before it gets worse.