Topic: Dr Franz Birkholtz (Pretoria, South Africa) (Read 299596 times)

Polycrates. · « **Reply #217 on:** March 25, 2014, 06:08:58 AM »

Yeah, that was quite the blunder. Not only basic math but common sense. What I was trying to get at is that taking for instance, a lengthening of the femur 6cm, you can lengthen the tibia 6cm rather than 4.8cm and still have a ratio far closer to the original than you would create with adding just 6cm to the femur. With average limb lengths you'd probably change the ratio by 3% or so, as you've demonstrated, but the change becomes more drastic the shorter the original limbs are. With sensible lengthening in the 5-6cm range, I don't think maintaining the ratio to equality is needed at all, since most people lengthen one or the other and get away fine with a far different ratio than the original. Ideally, like you asked, I suppose you would if you wanted exactness. Nevertheless, you're completely correct and I'm quite the idiot for telling you that the opposite would be correct, and I'm sure your question was intended for Dr. Birkholtz anyway, so I'll let him answer.. Take it as a momentary lapse of reason. Sorry.

Polycrates. · « **Reply #218 on:** March 25, 2014, 06:10:21 AM »

double post...

Franz · « **Reply #219 on:** March 25, 2014, 08:27:56 AM »

Quote from: Dingo on March 24, 2014, 01:00:29 PM

So ideally, if one is able to do 2 LLs, one should aim to lengthen tibiae around 80% of the amount lengthened previously in the femurs to maintain the bio-mechanical ratio.

For example:

Femur: original length 40cm + 6cm of lengthening = 46cm final femur length

Tibia: original length 32cm + 4.8cm of lengthening = 36.8cm final tibia length

Original ratio: 32 / 40 = 80%

Increase ratio: 4.8 / 6 = 80%

Final ratio: 36.8 / 46 = 80%

Absolutely correct. One of the reasons why we advocate 4-5 on tibias and 5-6 on femurs.

TRS · « **Reply #220 on:** March 30, 2014, 12:18:41 PM »

Quote from: Franz on March 14, 2014, 05:57:39 PM

In tibias the mechanical and anatomic axes are parallel, thus it should correspond. There may be some subsidence after frame removal though.

Can one prevent callus subsidence and height loss by doing LON instead of external and LATN, since the IM rod will be in place before frame removal?

What is the expected range of subsidence (min-max) after frame removal?

Franz · « **Reply #221 on:** March 30, 2014, 04:01:51 PM »

Hi TRS,

subsidence in the region of 5-10mm. Only a problem with externals only. With LATP it can be prevented with meticulous surgical technique.

Rgds,

FFB

Franz · « **Reply #222 on:** March 30, 2014, 04:30:17 PM »

Pics as promised.

State of the art technology in action...

Franz · « **Reply #223 on:** March 30, 2014, 04:31:22 PM »

The office. Where all the thinking happens!

Franz · « **Reply #224 on:** March 30, 2014, 04:32:55 PM »

Main hallway inside the hospital. Why does it always smell of antiseptic?

Franz · « **Reply #225 on:** March 30, 2014, 04:34:34 PM »

TSF frame for femoral re-alignment and lengthening being performed. Sorry about the blood.

Franz · « **Reply #226 on:** March 30, 2014, 04:35:40 PM »

The entrance to the children's ward. They get cartoons on the walls.

Franz · « **Reply #227 on:** March 30, 2014, 04:40:16 PM »

Modern operating theatres

Franz · « **Reply #228 on:** March 30, 2014, 04:40:54 PM »

More OR

Franz · « **Reply #229 on:** March 30, 2014, 04:42:12 PM »

Reception@walkamile.co.za

Franz · « **Reply #230 on:** March 30, 2014, 04:44:05 PM »

Teaching other surgeons from all over in our viewing room

Franz · « **Reply #231 on:** March 30, 2014, 04:46:09 PM »

Unitas is the largest private hospital in SA and has 500 beds.

It is owned and run by Netcare. Our practice is a completely separate entity and we are not employed by the hospital.

Franz · « **Reply #232 on:** March 30, 2014, 04:47:33 PM »

The woundcare room in our office. This is normally where adjustments take place.

Arche · « **Reply #233 on:** March 30, 2014, 05:00:37 PM »

Wow Dr. Birkholtz, these photos are amazing. You're doing God's work!

Franz · « **Reply #234 on:** March 30, 2014, 05:05:22 PM »

Tx Arche. It is indeed a calling.

Cooper · « **Reply #235 on:** March 30, 2014, 05:09:09 PM »

Thank you dr. Franz for pictures.

Picture does speak thousand words

!

OverrideYouGenetics · « **Reply #236 on:** March 30, 2014, 06:27:23 PM »

looks ace those pictures, some of the setup reminds me of the hospital standards in my country so I am very happy with this.

Wannabegiant · « **Reply #237 on:** March 30, 2014, 06:52:01 PM »

Quote from: Franz on March 30, 2014, 04:01:51 PM

Hi TRS,

subsidence in the region of 5-10mm. Only a problem with externals only. With LATP it can be prevented with meticulous surgical technique.

Rgds,

FFB

Wow...i cant believe this, is subsidence common? i mean is there nothing one can do to prevent it when doing externals only? It would mean that i would likely have to lengthen 5 cm to get 4 cm in the end, and thats not counting the pin bending i will have to make up for..

It sounds terrible and really there should be some kind of way to prevent it..im really worried now. Especially when doing small ammounts 4 cm, losing 10 mm would be catastrophic.

paco1 · « **Reply #238 on:** March 30, 2014, 07:48:01 PM »

That is my concern too only with external. Because of that i am thinking in LON.
i think you should make mínimum 4,5cm, because you will lose some milimetres.

Wannabegiant · « **Reply #239 on:** March 30, 2014, 07:59:45 PM »

Quote from: paco1 on March 30, 2014, 07:48:01 PM

That is my concern too only with external. Because of that i am thinking in LON.
i think you should make mínimum 4,5cm, because you will lose some milimetres.

Logically it would seem that Subsidence occurs because of removing the frames to early, the bone might be solid enough to hold the body weight but still not completely solid. If you have the frames on long enough for the bone to become as hard as it can, it should not be able to compress and removing a few pins with the frame removal should not have any effect on the new calles that solidified between the pin sites.

But i dont know of course and would appreciate if Dr. Franz could offer a deeper insight to subsidence and why it happens and what can be done to prevent it.

paco1 · « **Reply #240 on:** March 30, 2014, 08:15:31 PM »

In the case of salameh's device, the bottom part of device is out when you have some consolidation after lengthening. Then he take off the screws bit a bit. Then the device is smaller, and it still support the body.
I think you need to stay with the device the time necessary for consolidation without urgency, perhaps minimun 1,5 months by centimetre and you should make somes milimetres plus, mínimum 0,5 plus to secure 4 cm because lose lengthening.
That it will be that i will make if i do the surgery only with external, with doctor salameh

Franz · « **Reply #241 on:** March 30, 2014, 08:21:23 PM »

Hi,

Subsidence is something we cannot fully explain. Logically if the bone is strong enough, the length should stay the same. There are however some patients where some length is lost gradually afterwards -> probably due to some 'plastic deformation' of the new bone. This is disconcerting. Especially since it tends to happen gradually and long after the procedure.
Most doctors would recommend slow destabilization of an external only frame, in order to strengthen up the bone gradually before frame removal.

Preventing subsidence? Using internal methods, or combinations of internal and external may be the answer...

Wannabegiant · « **Reply #242 on:** March 30, 2014, 08:32:24 PM »

Quote from: Franz on March 30, 2014, 08:21:23 PM

Hi,

Subsidence is something we cannot fully explain. Logically if the bone is strong enough, the length should stay the same. There are however some patients where some length is lost gradually afterwards -> probably due to some 'plastic deformation' of the new bone. This is disconcerting. Especially since it tends to happen gradually and long after the procedure.
Most doctors would recommend slow destabilization of an external only frame, in order to strengthen up the bone gradually before frame removal.

Preventing subsidence? Using internal methods, or combinations of internal and external may be the answer...

Thank you for the answer, this is definitely concerning, i guess i will have to lengthen around 4,5 cms to make sure..

But it seems like if plastic deformation is the explanation, then it could happen after the surgery to remove the internal nails as well.. or maybe after a year or so when the nail is removed, is long enough for subsidence to no longer be possible..

Ive looked at 2 studies about this:

one study claims that the median subsidence loss was insignificant at around 0.28 - 0.6 mm, such a small loss would be acceptable to me.

The other one however reports the large losses mentioned in this thread...and it doesnt even seem to be uncommon to experience large losses, some even above 3 cm..that must be a case of removing the frame way to early..

http://informahealthcare.com/doi/full/10.3109/17453674.2010.533934

http://www.ncbi.nlm.nih.gov/pubmed/18923832

However reading further, it is interesting that the positive study actually argues against the other study where large losses where reported, and the authors of the first study acknowledged the errors that where brought up. So it seems the positive study of less than 0.6 mm subsidence loss on average is the more reliable one based on this. I hope it holds true, still gonna lengthen some mm extra to make up for the potential loss.

paco1 · « **Reply #243 on:** March 30, 2014, 08:33:41 PM »

Thank you very much Frank, for your answers.
You look like a very good option but the idea that you only have made two cosmetic lengthening it go me to back.

paco1 · « **Reply #244 on:** March 31, 2014, 09:46:51 PM »

it would be good idea to wear somes braces or cast when you take off the device to protect the new bone.If one person makes only external.What do you think?

KiloKAHN · « **Reply #245 on:** March 31, 2014, 09:55:58 PM »

Excellent update, Dr. Birkholtz. Looks like a great hospital.

ChrisIsaak · « **Reply #246 on:** April 01, 2014, 12:07:05 AM »

Quote from: paco1 on March 30, 2014, 08:33:41 PM

Thank you very much Frank, for your answers.
You look like a very good option but the idea that you only have made two cosmetic lengthening it go me to back.

Why, paco? My doctor had only done 30-ish cosmetic lengthenings but everything went great. Keep in mind that these doctors have done hundreds to thousands of normal, non-cosmetic lengthenings both for achondroplasia patients (dwarfism) and leg length discrepancy lengthenings. It's actually better for the doctors as they face all sorts of complications in these patients and become more experienced in treating possible complications in simpler cosmetic cases. That being said, isn't it also technically the same thing? Leg length discrepancy or cosmetic, one leg or both legs, it's the same procedure.. (Yes there's increased risk of fat embolism when you add a leg, but it's not a problem in bilateral lengthenings when the doctor is experienced, the risk is surpassed with proper venting methods during surgery and post-op medications). In brief.. You make it seem like Dr.Birkholtz has only done two surgeries so far (I know you don't mean that, no offense) whereas his actual experience is so much more than that. I only wrote this to assure you that hopefully everything should go fine.

Keep Growing · « **Reply #247 on:** April 09, 2014, 08:55:11 AM »

Hello, Dr. Birkholtz,
Can you please give a rough estimation, for a normal patient, after how many months can he walk in crunches ?
Thank you,

Limb Lengthening Forum

Author Topic: Dr Franz Birkholtz (Pretoria, South Africa) (Read 299596 times)