This with a bit of extra code I use in my forum...
http://www.marine-hunters.co.uk
Change this
$result = $db->query('SELECT t.id, t.poster, t.subject, t.posted, t.last_post, f.id AS fid, f.forum_name FROM '.$db_prefix.'topics AS t INNER JOIN '.$db_prefix.'forums AS f ON t.forum_id=f.id WHERE f.id='.$fid.' AND t.moved_to IS NULL ORDER BY '.$order_by.' DESC') or error('Unable to fetch topic list', __FILE__, __LINE__, $db->error());
to this
$result = $db->query('SELECT t.id, t.poster, t.subject, t.posted, t.last_post, t.num_replies, f.id AS fid, f.forum_name FROM '.$db_prefix.'topics AS t INNER JOIN '.$db_prefix.'forums AS f ON t.forum_id=f.id WHERE f.id='.$fid.' AND t.moved_to IS NULL ORDER BY '.$order_by.' DESC') or error('Unable to fetch topic list', __FILE__, __LINE__, $db->error());
Then if you use this
$cur_topic['num_replies']
it will give you the replies to that topic.
My line of code is
<a href="'.$pun_config['o_base_url'].'/viewtopic.php?id='.$cur_topic['id'].'&action=new" title="'.pun_htmlspecialchars($cur_topic['subject']).'">'.$cur_topic['num_replies'].' Comments...</a>
so that when you click on the comment link takes you straight to that topic.
Example here
Bit long winded so any problems let me know.