If the leaves look OK and the pears appear healthy, I don't think it is time to worry.

My pear trees, with the exception of my Bosc, are much slower growing than my apple trees. They aren't as full and they aren't nearly as tall. They don't put out nearly as much new growth every year, and they don't set nearly as much fruit.

Are your pears on a more dwarfing rootstock?

Both my Asian and the European pears are slower than the apple trees.

My Bosc is a huge gangly scrawny monster, twice the height of the apple trees the same age. Like a very spoiled child, I allow her to do as she wishes, because she provides me with a large number of huge, gorgeous, delicious pears. She started bearing very young, and I thin and thin, but still the weight of the pears have pulled her skinny branches into all sorts of weird shapes.

My favorite tree. As long as she can sing and tap dance like Shirley Temple, I indulge her every wish.