Scales missing from leg?

[Foursteels]

I haven't seen RT much this week because he's in his hide when I get home from work, but today I found him out walking in his enclosure and noticed scales missing from one leg. He's outdoors 24/7 with no other inhabitants in his enclosures. He was fine Sunday when I last saw him. Has anyone seen this in their tort?

 

[MPRC]

Could it be damage from trying to escape?
Is there blood? Does it smell? Is it sensitive?

 

[Foursteels]

No blood and it doesn't smell and there is no broken skin or anything. Just looks like smooth skin with no scales.

 

[Tom]

Might he be digging against something hard like concrete or a rock? When they park headfirst at night, they will often dig at whatever they've butted up against. What is your tortoise butted up against at night?

Might rodents be a possibility? Is he closed off at night in a secure box, or is he out in the open?

 

[Foursteels]

I have plastic buckets that I've made caves out of. They have 3-4 inches of topsoil in them and he goes in and kind of buries himself toward the back. Sometimes you can hear him scratching against the plastic with his claws. I don't believe a rodent could get into the enclosure as it's 18" high and has a screen top.