Bump?

Hey guys i'm a little worried about what is on my dog, aces tail.

I was playing with him this morning and noticed a bump, about the size of a small grape on his leg. I felt it and it didn't really feel connected to him, if you know what I mean. Last year he was hit by a car and got a plate and pins put into his leg, and this bump is where his scar just about starts. I can press on the bump, squeeze it, and it doesn't bother him. I'm probably gonna take him to the vet monday, and I was curious if this sounds major or not. I was thinking a cyst.

Thank you.

-Joe

It's always wise to have them checked and aspirated. Chip has one on his side.. results were fine, but vet measured to watch.

What would you say it is?