Hey Dr Franz, I have some follow up questions
1. Is it true that doctors who use Fitbone for cosmetic femur LL tend to insert nails retrograde but doctors who use Precice tend to insert nails antegrade? Almost all cases of cosmetic femur LL I have seen on the internet of Precice involve antegrade insertion but those of Fitbone involve retrograde insertion. Is there any correlation here? Even the marketing illustrations we see from the companies have this pattern.
2. How do we make a trade off between high chances of permanent knee pain through retrograde insertion and alignment issues with antegrade insertion?
3. Can Fitbone be left in the body for long? Since there is no rare Earth magnet in it, is it as serious a matter to leave it in the body for a very long time?
4. How many Fitbone nails have been inserted worldwide? With Precice the number stands at around 13.000 so it would be interesting to compare. Understandably, Fitbone has only recently entered the global market so this number would probably not imply much.
5. How does Fitbone's reliability compare with that of Precice? I am talking about device failures leading to inability to distract.
6. Roughly speaking, can you estimate how many times is Fitbone stronger than Precice in terms of weight bearing? Since each nail comes in 3 sizes, please compare the respective sizes if possible.
Thank you.
Important disclaimer: I have no financial interest in Fitbone and am not promoting the nail as such. I also use the Precice 2 quite extensively in my practice. With this in mind, I will limit my responses to the questions above in the context of my position:
1) Yes. Traditionally surgeons had to be trained by Prof Baumgart to use the nail and his reverse planning method described for retrograde insertion. There are some of us who, based on the patient's anatomy choose to proceed with antegrade nailing, similar to Precice.
2) Your surgeon would be the best person to guide you.
3) It has an electric motor inside, as well as moving parts, so should ideally be removed.
4) I am not sure of the exact number, but thousands since 1997.
5) I do not know to be honest. Prominent limb lengthening surgeons would not be using the nail if it was prone to failure.
6) Hehe. Don't really have time to run comparisons. These are not necessarily the best comparisons, as it is immaterial how strong a nail is if the patient's pain stops them from mobilizing. Even with the so-called 'non-weight bearing' nails, it is possible with judicious physio and clever tricks to get people mobile on walking frames instead of wheelchairs only.