stevema on "[Plugin: WordPress SEO by Yoast] Changed post title not attracting links on wordpress SEO"

I shortened a post title to three words. (The post has been around for six months or so with a longer title.) However, when I put these three words on pages they do not appear linked to this post. Generally works ok otherwise.
My site is http://www.back-doctor.co.uk
The post is as follows http://www.back-doctor.co.uk/degenerative-disc-disease/
The text which is supposed to link to it is at the bottom of the following page:
http://www.back-doctor.co.uk/back-pain-html/

http://wordpress.org/extend/plugins/wordpress-seo/