Leicester need a good run with injuries. They have a decent squad but 2 or 3 players are crucial, same as with any team.
Last season they were nailed on champions league prior to shutdown, but had key players injured when we came back and fell away badly. This season the only key injury they've had out is Ndidi who missed 9 games. The Turkish CB was out but Fofana is probably better anyway and the Turk can't get back in the team now. Maddison was restricted to the bench for the first 3 games but they won those anyway.
Elsewhere, City have had issues with a striker but all their other key players have been fit and mostly played every game. Same too with Spurs and Man United, hardly any injuries between them. Chelsea have generally worked with a fully fit squad. Pulisic and Ziyech have had injury problems but they have top drawer cover for both. Arsenal haven't had any severe injuries that I'm aware of and, although Liverpool have had their problems at CB, the rest of the squad has been pretty much free of injury apart from Thiago and Jota. They moan about Jota being out but Salah, Mane and Firmino have been available every game. Southampton have been pretty much injury free bar a handful of games when Ings was missing, whilst Wolves have seemingly fallen apart because their main striker is out.
If we put aside Liverpool's issues at CB, and City's issues with the striker, out of all the teams challenging, only Everton have had a really bad run with injuries. Only Doucoure has been ever present and out of what was arguably our preferred starting XI at the beginning of the season, Holgate has missed 9 matches, Digne and Coleman 8 each, Allan, James and Gomes 5 each, and Richarlison 4. It would have been more had we not had 2 matches cancelled.
I'm not looking for excuses, in fact it's the opposite because I'm amazed that we are where we are given the injuries we've had to our key players. All I'm saying is that we're still in touch despite these injuries. If we can get a decent run and other clubs start picking up injuries, nothing is out of the question. Plus all the teams around us start their European fixtures again in 4 weeks time and that is bound to work against them. We need luck with injuries plus the sort of VAR decisions we were getting up to the derby match. But if we get the Everton back that we saw in those first 7/8 games of the season, I think it would be daft to rule us out completely, and certainly a top 4 place is achievable.