Rear bumper 'shocks'

I have an '89 Volvo,240DL, I was rear ended so hard that the shocks on the bumper
were pushed (the one at the passenger side) so hard that I can’t bring them back to
its normal place. A mechanic friend of mine tells me that these shocks,once they are
pushed that far in are not ment to be brought back and I need to replace them …
that doesnt make sense to me , but who am I to know? is this true? I really would
like to fix this, I do have another pair of these shocks at hand but is it really
necessary to change them? Please enlighten me if you know!
Gracias

Yep. They’re One-Time use impact absorbers. Once they’ve collapsed they need to be replaced.

Tester

Tester, thank you, I will do that!

And get your car inspected, more damage might have been done.

Yeah, if they are pushed in that far, they should be replaced. They are only meant to absorb the shock once. Guess its cheaper that way and will still meet the crash requirements.