But the Liverpool boss is confident a solution for the right-back's issues will soon be found, with the club's medical team seeking specialist help in order to expedite matters.
Clyne featured in 41 games in all competitions for the Reds last term, but has been sidelined since appearing in a friendly meeting with Tranmere Rovers back in July.
When asked about the defender's fitness at his pre-West Ham United press conference, Klopp replied: "Not that good. He was on a good way and then he had a little setback but we are on it.
"That’s how back problems are. Probably, it's a problem most people had - when you get a little bit older you see the back is a really weak part of your body.
"We all know how that can take a long time and we have to make him 100 per cent ready and that's what he is not in the moment.
"That is not the best thing, especially not for him, but we are on it, we showed him to specialists all over the world and it’s not a big problem, it just needs time."