Bruising

[Reme77]

My 12 yo DS has a line of deep bruising down each arm. He's no idea how and it doesn't hurt. Should I be concerned, he's just showed me and I'm in bits. I don't know whether to get a GP appointment. I can't even think what could cause bruising in this way.
Wondered if anyone had any thoughts
Many thanks

Bullying

Are there bruising elsewhere? Could this be mechanical? Is he feeling well in himself? Has he had unexplained nose bleeds and/or bleeding gums? If so he will need blood tests

Nothing hurts, he's adamant he's no idea how. No other bleeding or bruises, just his arms in a vertical line. Always happy to and from school, plenty of after-school activities so I don't think bullying but could be kids messing about I guess. Going to have another chat with him but was wondering if it could be a medical issue. Thanks all

I get bruises like that from leaning with all my weight on a fence at work, essentially dangling off it. They look horrific but don't really hurt. Unfortunately I haven't learnt from the first set of bruises.

Thanks. Well don't I feel a fool. Turns out he decided to suck his skin to see what happened and when it turned purple he carried on down his arm! Yep he gave himself a line of love bites! We've had a long chat. Thanks all

Could he have been leaning against something (like previous poster) or doing something that put pressure on his arms, as it weird the bruises are the same on both arms, rather than random. I remember years ago waking up one morning with almost symetrical bruising on my arms and legs. I was freaked out until I remembered that the night before I'd been given the bumps for my birthday - bruises were finger marks from where I'd been grabbed! Could it be something like that? A rough game for example?