As Phil said:
Look at the dates of these threads. Many of them were from the "Golden age" of MedHelp and are at least 6 years old.
Personally, I ignore many of these posts, because I do look at the dates. If the post is from 2007, I'm not going to reply, because I figure its old news.
If you must refer to another post, copy its URL and paste into your new post. You can say:
I feel just like so and so in this post
http://www.medhelp.org/posts/Pain-Management/I-had-Total-Knee-Replacement-5-weeks-ago-and-I-am-still-suffering-severe-pain-especially-at-night/show/3243
This way we can refer if need be, but your post will get more attention because it is contemporary.
Also, pick a descriptive subject for your post. The better information we receive, the more we can help.
~Tuck