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New Lengthening technique...???

Hi, I was just reading and article and it seems as though there is a new procedure for lengthening that is still in the developmental stages that is a plate that goes on the bone and the distraction is done using a small rench through an incision in the skin. Anyone heard of this? Apparently it was talked about at the American Association of Orthopaedic Surgenons this past March. Here is the article:

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 (

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.

That is great information. Thank you! I guess they are constantly working on research for this procedure...


There seems to be indication that Dr. Paley uses this for lengthening per his video at I'll post again when I get more info...not sure who is a candidate.

I looks like what they invented in England has now made it to the US as the "Precise" system ( ) and I found an interesting animation video of it here (no blood)