Limb Lengthening Forum
Limb Lengthening Surgery => Height & Proportions => Topic started by: MrJames on August 19, 2019, 11:38:02 AM
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hi,
legs height:
https://ibb.co/tZGK2w5
How is the ratio of femur and tibia calculated?
for example:
femur bone : 335mm
tibia bone : 324mm
Thanks.
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tibia/femur = 0.8 on average
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tibia/femur = 0.8 on average
Thanks.
My ratio result: (335/324)
1,03
if +7cm femur ratio result: (335 + 70)
1,25
if +6cm tibia ratio result: (324 + 60)
0,87
According to these results, is my tibia lengthening better?
Maybe I measured the bone size wrong from the x-ray, but I don't think you're going to notice small mms.
When measuring femur and tibia, the length of the bone is measured?
For example, are my X-ray measurements correct?
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Ur wrong your Ratio is arround 0.96
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Tibia length has to be 80% of femur.
Sry for bad english 😝
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Ur wrong your Ratio is arround 0.96
How do you calculate ?
is 0.96 normal legs ratio? (Non lengthening)
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hi,
legs height:
https://ibb.co/tZGK2w5
How is the ratio of femur and tibia calculated?
for example:
femur bone : 335mm
tibia bone : 324mm
Thanks.
Hi James, from where did you got these numbers from? Looking at your x-rays if the numbers are measurements taken from the lines you have drawn than they are wrong. pls look up online to see where the femur and tibia bones start and finish.
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Hi James, from where did you got these numbers from? Looking at your x-rays if the numbers are measurements taken from the lines you have drawn than they are wrong. pls look up online to see where the femur and tibia bones start and finish.
I had an X-ray. There are measuring tools from X-ray application.
But I do not know where the lengths of the femur and tibia are measured :)
I just measured the size of the main bone. (femur and tibia)
Do you know how to measure? (point to point etc.)
new calcuate:
https://ibb.co/DQ823Zw
The difference from the other measurement:
I measured the femur from the vertex of the bone.
There is not much information about measurement on the Internet.
I made this measurement by looking at x-ray pictures on the internet.
Size results:
404 / 350 = 1,15
Does my legs have a tibial ratio with the femur? :)
They say 0.8 in the forum, but the average of femur and tibia in medical research on the Internet is 1.20.
I don't know what the 0.8 value in the forum is.
(https://i.ibb.co/L63VWmc/ratio.png)
(https://i.ibb.co/gDyXzyJ/ratio2.png)
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looking at x-rays, the new measurements seems more accurate. Tibia line should finish at the end of tibia bone but you are overlapping it to the ankle bone so your tibia measurement might be a little less than you have now.
Your femur to tibia ratio seems standard to me, I am enclosing a link that will show you how to measure tibia and femur length.
http://www.rundocrun.com/the-orthotic-difference.html
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looking at x-rays, the new measurements seems more accurate. Tibia line should finish at the end of tibia bone but you are overlapping it to the ankle bone so your tibia measurement might be a little less than you have now.
Your femur to tibia ratio seems standard to me, I am enclosing a link that will show you how to measure tibia and femur length.
http://www.rundocrun.com/the-orthotic-difference.html
Thank you.
What is the 0.8 femur tibia ratio that people say in the forum?
Is that another measure?
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tibia/femur = 0.8
femur/tibia = 1.2
...
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Thank you.
What is the 0.8 femur tibia ratio that people say in the forum?
Is that another measure?
It means that ideally tibia should be about 80% of the length of femur, give or take 2-3 percents. If femur is 40cm than tibia is about 32 cm. Once you will measure correctly you will see that you are with in the acceptable normal range i.e., tibia is between 78%-82% of the femur length is very standard. IMO after lengthening, for the sake of functionality and aesthetics, at most tibia length should be with in 70-90% of the femur length.
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exactly!
It's a ratio calculation: tibia / femur = 0.8 means tibia = 0.8 * femur, so tibia = 80% of femur
On the other way: femur / tibia = 1.2 means femur = 1.2 * tibia, so femur = 120% of tibia
It's the same same equation resolved differently.
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It means that ideally tibia should be about 80% of the length of femur, give or take 2-3 percents. If femur is 40cm than tibia is about 32 cm. Once you will measure correctly you will see that you are with in the acceptable normal range i.e., tibia is between 78%-82% of the femur length is very standard. IMO after lengthening, for the sake of functionality and aesthetics, at most tibia length should be with in 70-90% of the femur length.
exactly!
It's a ratio calculation: tibia / femur = 0.8 means tibia = 0.8 * femur, so tibia = 80% of femur
On the other way: femur / tibia = 1.2 means femur = 1.2 * tibia, so femur = 120% of tibia
It's the same same equation resolved differently.
Thanks. I understand.
0.8 and 1.2 different values but femur and tibia ratio calculation is the same.
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I made a simple ratio calculation excel file.
I hope there are no mistakes :)
Download links:
https://gofile.io/?c=l0EP8d
https://file.io/D26a8N
https://quickfileshare.org/Zwy/Ratio_Calc.xlsx
https://filebin.net/bibpgyc5wduivsxm/Ratio_Calc.xlsx?t=l6gx0p5l
(https://i.ibb.co/nBdDynq/ratio.png)
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Fixed calculate.
https://gofile.io/?c=XHBnRA
https://file.io/4C2Xcj
https://filebin.net/wvlogzwhyuddql1h/Ratio_Calc.xlsx?t=wcdh9zzf
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what if i have equal length ? my tibias 39 and femur 39 cm ( I lenghten tibias form 33 to 39cm )
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what if i have equal length ? my tibias 39 and femur 39 cm ( I lenghten tibias form 33 to 39cm )
I do not know this :)
This is only medically to calculate the lower and upper bone proportions.
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Can you repost the macro, the link doesn't work, tks :)
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Can you repost the macro, the link doesn't work, tks :)
;)
https://www84.zippyshare.com/v/pdW77fkk/file.html
https://turb.to/rnf3sg3505id.html
https://userscloud.com/eyw7eid7ieto
https://takeafile.com/?f=wipogogaje
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(https://i.ibb.co/k30M7qB/Clipboard-1.png)
Google Drive (http://drive.google.com/uc?export=view&id=1LjuOli3zr5V64efyTQy7juAPnNT2xd6-)
zippyshare (https://www46.zippyshare.com/v/IriFmeTN/file.html)
userscloud (https://userscloud.com/775nk9lngbcs)
turbobit (https://turb.cc/ctuhgyhf1umm.html)
letsupload (https://letsupload.io/4eudh/Ratio_Calc.xlsx)
mediafire (https://www.mediafire.com/file/irfyndu0zk3js9w/Ratio+Calc.xlsx/file)
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damn, people on this forum really not that great at math. you literally divide tibia length by femur length in either inches or cm. idk whats going on LOL
It aint rocket science folks ;D
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damn, people on this forum really not that great at math. you literally divide tibia length by femur length in either inches or cm. idk whats going on LOL
It aint rocket science folks ;D
Many people don't know how to simple calculate the femur - tibia or tibia - femur ratio.
For the lazy :) 8)
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My tibia is longer than the femur.
tibia 39 cm.
femur 36 cm.
That's why I have to wait for stryde to come back. It would look really weird if I’ll do tibia.
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My tibia is longer than the femur.
tibia 39 cm.
femur 36 cm.
That's why I have to wait for stryde to come back. It would look really weird if I’ll do tibia.
It's not. Do a full body EOS scan and you will see that it is not longer
Barring some extreme medical deformity, all humans femur are longer than tibia
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The doctor who was going to perform the surgery examined me. I do not think he was wrong. And there are many people whose tibia is longer than the femur
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False statement. There is not "many" people who have longer tibia than femur. You are either mixing up the numbers or your doctor is an idiot. I'll just safely assume you are mixing up your numbers, all orthopedic surgeons know femur is longer than tibia. Effectively no one has a longer tibia than femur. If you do then you are genetically messed up in more ways than just your legs.
It can appear longer, but is not.
You need an EOS scan. I will give you 1000$ in wire transfer if your tibia is actually longer than femur. Because it is not 🙄
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I agree with you that most people have a femur longer than the tibia. But you can not say that everyone is like that. My doctor is one of the most famous in the world, and he's probably not an idiot, there are dozens of people here in the forum who did the surgery on him.
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I agree with you that most people have a femur longer than the tibia. But you can not say that everyone is like that. My doctor is one of the most famous in the world, and he's probably not an idiot, there are dozens of people here in the forum who did the surgery on him.
"most" people is an understatement, it is probably more than 99.99999% of people who DON'T have a longer tibia than femur (meaning, their femur is longer). If the average tibia/fem ratio is 0.80 with a standard deviation of 0.03, then 3 standard deviations up would be 0.89 (tibia shorter than femur), which would be the top 0.15% (99.7% is 3 standard deviations coverage centered at 0.80), and 4 standard deviations up would be 0.92 (tibia still shorter than femur), which would be the top 0.0005% (99.99% is 3 standard deviations coverage centered at 0.80), and 5 standard deviations up would be 0.95 (again, tibia still shorter than femur), which would be the top 0.00003% (99.99994%% is 3 standard deviations coverage centered at 0.80), which at this point is the 5-sigma threshold for scientific observations to become a discovery.
At this point it is 1 in 3.5 million people who have a 0.95 tibia to femur ratio, and the tibia is STILL shorter than the femur.
The 6th standard deviation above the mean would be an astronomical number, and even then it is still not more than 1, it is 0.98. You'd need to hit the 7th standard deviation which would be much much much higher than 1 in 3.5 million to achieve a ratio of greater than 1, which would mean the tibia is longer than the femur.
For all purposes and intent, a longer tibia than femur is not natural and doesn't occur in more than 99.9999% of normal humans.
Why do I care enough to type all this? I don't, I am just bored and like math and have nothing to do. *shrugs*. Nothing personal Ozzi lol. ;) :-*
References:
https://pubmed.ncbi.nlm.nih.gov/26398436/
https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule
https://blogs.scientificamerican.com/observations/five-sigmawhats-that/#:~:text=So%2C%20what%20does%20five%2Dsigma,about%201%20in%203.5%20million.
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"most" people is an understatement, it is probably more than 99.99999% of people who DON'T have a longer tibia than femur (meaning, their femur is longer). If the average tibia/fem ratio is 0.80 with a standard deviation of 0.03, then 3 standard deviations up would be 0.89 (tibia shorter than femur), which would be the top 0.15% (99.7% is 3 standard deviations coverage centered at 0.80), and 4 standard deviations up would be 0.92 (tibia still shorter than femur), which would be the top 0.0005% (99.99% is 3 standard deviations coverage centered at 0.80), and 5 standard deviations up would be 0.95 (again, tibia still shorter than femur), which would be the top 0.00003% (99.99994%% is 3 standard deviations coverage centered at 0.80), which at this point is the 5-sigma threshold for scientific observations to become a discovery.
At this point it is 1 in 3.5 million people who have a 0.95 tibia to femur ratio, and the tibia is STILL shorter than the femur.
The 6th standard deviation above the mean would be an astronomical number, and even then it is still not more than 1, it is 0.98. You'd need to hit the 7th standard deviation which would be much much much higher than 1 in 3.5 million to achieve a ratio of greater than 1, which would mean the tibia is longer than the femur.
For all purposes and intent, a longer tibia than femur is not natural and doesn't occur in more than 99.9999% of normal humans.
Why do I care enough to type all this? I don't, I am just bored and like math. *shrugs*. Nothing personal Ozzi lol. ;) :-*
References:
https://pubmed.ncbi.nlm.nih.gov/26398436/
https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule
https://blogs.scientificamerican.com/observations/five-sigmawhats-that/#:~:text=So%2C%20what%20does%20five%2Dsigma,about%201%20in%203.5%20million.
So Femurs are typically longer then Tibias.
By design it would seem Tibias are shorter for a reason (mechanically). Would lengthening them and ultimately changing the ratio In favour of the Tibia place the body at a disadvantage?
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So Femurs are typically longer then Tibias.
By design it would seem Tibias are shorter for a reason (mechanically). Would lengthening them and ultimately changing the ratio In favour of the Tibia place the body at a disadvantage?
Increased wear on the hip and knee and potential for more arthritic issues if your tibia/femur ratio gets higher (tibia LL). This can happen the other way around too with femur lengthening, but lesser degree.
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Increased wear on the hip and knee and potential for more arthritic issues if your tibia/femur ratio gets higher (tibia LL). This can happen the other way around too with femur lengthening, but lesser degree.
Ah I see, it sounds as Femurs would be a wiser choice for one procedure?
Or ideally both Segments F +T to avoid complications mentioned.