bone growth test

1.4 m seems at 50% height curve or might be 40%. Doesn't seem "much lower". Some kids grow late

Has someone actually been tracking his height & weight through his development (i.e. his doctor, marking on the wall at home, etc.)? If not, someone needs to start doing that. As long as they are not crossing expected trajectory percentile lines on growth charts, they're fine - you would see this as growth stunting.

We had it done when my youngest was maybe 4 or 5. It was because her growth percentile was continually dropping off her curve for about a year continually. She started some where near the 25 percentile and then was under the 1st percentile. We did the tests, they just said she was a 'late bloomer' She still remains small. She is 13 and 148 cm.

It's only if they fall off their curve for a while.

Unless he is dropping percentile (ie from above 75% to below 50%, etc) from the growth curve. otherwise nothing to concern, as long as he is following the trajectory. As well, some kids are late boomer, if you and your spouse are late boomer, chances are your kids will be.