So lets talk about this.
Precice 1 was a modular nail that had to be assembled on the back table . It had weld points as well that were very fragile.
They would break upon removal and cause another set of issues.
Precice 2 (by the way, we just call it PRECICE, as the modular version is not accessible nor manufactured anymore.) is an amazing implant. The most accurate and versatile of the internal lengthening devices. The key part that seemed to be overlooked in this above article is:
Experienced surgeons know that the 8.5mm nail is not as strong nor rotationally stable and should never be used for cosmetic lengthenings. We use it for very small pediatric patients or for humeral lengthenings.
Thicker PRECICE and even Stryde also routinely bends, along with all other internal lengthening devices. It is by design as elasticity of a mechanical implant is desired to prevent breakage. I have even brought it up here on the forums when discussing anatomical vs mechanical axis deviations. This elasticity is taken into account by the engineers who design the implants.
Furthermore, all orthopedic implants can fail. From joint replacements to plates and screws to nails used to fix fractures. They're inert objects with mechanical properties.
That being said, one has to be careful! Even Stryde breaks. Sometimes its not only about the implant, but about the abuse the nail is submitted to. that's why I always cringe when I see surgeons advertise normal levels of activities during lengthening. Or patients posting videos of themselves running during active lengthening. IT's deceitful as too much weight bearing or activity can accelerate implant failure.
Thanks for your perspective! Pretty cool to have a LL surgeon who is willing to hang out here and reply. Can I ask a few follow up questions?
First I think it's interesting you say even the Stryde can bend. I would think that the steel units (Stryde, Guichet, Betz) should all be pretty stable against bending as long as they are used below their weight tolerances. In principle, that is what the weight tolerances are supposed to determine. If they are bending beneath their weight tolerances, then either as you say people are doing stupid things like jumping up and down, or the weight tolerances are wrong and should be redefined lower.
If someone had a steel unit like these, when would you think it should be considered reasonable to return to basic office work (walking around the office) even once or twice a week?
On a related subject, I also wonder if you can read this study and let me know what you think:
http://www.limblengtheningforum.com/index.php?topic=66326.0That meta-analysis showed PEMF/LIPUS allowed 25% faster bone healing in distraction osteogenesis. Do you think most LL surgeons are not aware of this finding? Or are they just skeptical for some reason? I would expect most LL surgeons would happily then add these modalities if it means faster consolidation. Faster consolidation = faster lengthening, quicker weightbearing, and less risk of device failure. Yet no one seems to be getting these unless there is a nonunion already presenting itself.
I lastly wondering if you wouldn't mind commenting on what you think about this:
http://www.limblengtheningforum.com/index.php?topic=66332.0Speaking in general terms (not about any one ortho in general), why do you think some orthopedic surgeons are so careless about the lengths of their screws? I am not an ortho myself but I am also a doctor. I had one patient of mine in chronic pain after a hip fixation post-trauma. Everyone kept saying the xrays were normal. Then I looked at them myself and the screws were similarly jutting out almost an inch into his soft tissue where he had pain.
It should seem obvious having screws digging an inch into your soft tissue every time you move would hurt but yet many orthos don't seem to think twice about it (in LL or general use) and radiologists also report this as "normal." Do you think this is just sloppiness? Rushing? Are orthos taught that this does not matter? Why not just do an extra x-ray in the OR to measure once more when the nail is in place before screwing it?
I don't mean this as a slam against orthos - I just find it puzzling that anyone would put such massively missized screws inside someone, expect to leave them there 2 years, and not expect problems from it. If they could have just taken the extra 5 minutes to pick the right sized hardware they could potentially save that person so much misery.
Thanks again for your participation here and I appreciate any candid thoughts you can provide.