New Lengthening technique...???

I've been adding a section on leg lengthening techniques to the PFFD guide for parents. The use of a key to increase the length is not new as it was used for osteocarcomas for years (where they remove a section of the bone and replace it with an expandable section).

In regards to osteosarcomas, from what I've read, the key-turning technique is depreciated because it either requires surgeries every time you want to do an adjustment or you still have the problem with a post through the skin. Quoting from one article

In the past, doctors had to lengthen the prosthetic with a key inserted surgically into the patient's leg—a costly procedure often followed by days of tearful post-op recovery.

More recent innovations have devices controlled by RF (radio frequency) implanted devices (E.g. springs, wires, ratchets).

The one I've seen that looked the best was developed in England (
http://www.memagazine.org/contents/current/features/moflife/moflife.html
where they use a worm gear, magnet, and a rotating magnetic field. The nice thing about it is that it is reversable - you can shrink as well as expand the length which the wires, ratchets and springs devices did not allow.

I contacted the author's of the article in 2003 when my daughter was born to see if
the technology could be adapted to PFFD. It makes sense as it would just be the same
thing but attached to a rod instead of replacing the bone. The lead doctor said it was not currently designed for PFFD - the device actually replaced the bone - instead of attaching to it. But they were working on a second model that might be feasable.