Because, as is clearly stated at the top of the thread, it is locked.
Old threads are locked to avoid necroposting.
They lock old threads here. That one's ten years old. Start a new thread if you've something relevant to say.
Note that it looks medical - you may find a new thread about medical problems is closed quite quickly these days.
Yes, we are not allowed to give medical advice or try to provide a remote diagnosis here on the PF. That is in the PF rules and is emphasized by the stickie thread at the top of the Medical forum. @larry909 -- please keep that in mind when posting in the Medical/Biology forum. Thanks.
What a great word.
Yes indeed. So, I suppose that "liking" an old post is necrophilia.
Separate names with a comma.