So, the funny thing is that you run that GCI and it kicks back a table with the name of the sub keys and that's it, but if you do a Select -Expand Name it gives the full HKLM\Software\Policies\Citrix. So there's the problem, Name actually contains the full name of the key, not just the last sub-key.
So, you want the subkeys that start with 1-9? Split it out by \
and just use the last one for each entry. Try this out:
(Get-ChildItem -Path HKLM:\SOFTWARE\Policies\Citrix).Name | ForEach {$_.Split("\")[4] | Where-Object {$_.name -Match '^[1-9]'}}