Hello, I just wondered if anyone knew what these could be? It's as though they're old blood in a line running across his bicep/upper arm rather than running down the arm. He is 12, noticed it this afternoon at school.
Submitted request to GP but not expecting to hear from them at this time on a Friday. Tried Googling but not sure what to Google?! Some similar ones don't look like this as they run down the arm in veins.
He doesn't remember hurting it. He's on crutches but surely it'd affect both arms?! I saw another reddit post sort of similar that said stretch marks but don't think his arms have grown?!