You have a number of errors interacting to result in your bug. The closest code to that you posted that functions is:

#!/usr/bin/perl -w
use warnings;

sub printElement(\%$)
{
   my $hash_ref = $_[0];
   my $key = $_[1];
   print $key." ".$hash_ref->{$key}."\n";
}

my %hash = (0 => 'a', 1 => 'b', 2 => 'c');
while(($key) = each(%hash))
{
   printElement(%hash, $key);
}
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A large fraction of your problem can be traced back to incorrect use of Prototypes. For one thing, note that by using the & you are disabling the prototype. As well, if you hadn't disabled the prototype, passing in a hash reference would violate the prototype. In the end, your real problem is that using %hash in list context results in resetting the iterator in each. This is one of the reasons many people favor keys for the kind of loop you are describing.

As a side note, consider using strict: see Use strict warnings and diagnostics or die.