Kissing spines - are they born with it or does it develop?

[Tangaroo]

Might seem a silly question but i just wondered whether it is something a horse can be born with or is it something that develops as they start work?

 

[TicTac]

Both. My horse has just had her KS op in which she had 4 pieces of bone removed. The vet thinks that she was born with her condition. She has very narrow spaces between her vertabrae which over the years with work etc quickly caused impingement ( of 7 vertabrae in her case)

I have a friend who's 4 year old had the op. She didn't realise it had a problem untill she tried to back it and it was having none of it!