Why won't my pear tree grow?

I have a row of 6 cordons planted 3 years ago. The second one along is a Packhams Triumph. It leafs up in spring and flowers well but grows no new stems or leaves, the trunk hasn't thickened, it sets no fruit. I treat it the same as all the others and they grow like crazy and fruit well for their age. I've dug around the roots and they look OK. I've sprayed it with seaweed and fed it extra, but it's stuck in a Groundhog Day, does the same thing every year. Any ideas? Will go on the rubbish heap this year if no-one can help it but I'm concerned about having the same problem with a replacement. The cordons are only 3 foot apart
Why won't my pear tree grow?
Hmm - odd - have you tried testing the soild around this pear?

It is an unusually heat requiring fruit - but I would have expected some development!

Doesn't it flower or fruit at all? What if you prune the apical shoots - does it branch or create new ones?
Reply:chop it down, its a dud
Reply:I think it might be dying coz ur saying that it has no leaves and If i were u i would put it in Rubbish heap by now