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Author Topic: If you have femur tibia ratio of 0.8, which one is better to be 0.7 or 0.9?  (Read 329 times)

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Bruce Wayne

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In other words, which bone to lengthen?

I just did my femur mockup and look like a freak whereas the tibia mockup looks good.
« Last Edit: June 08, 2018, 09:57:43 PM by Bruce Wayne »
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Johnson1111

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I think the Tibia mockup will always look better because longer tibias look really good on men whereas longer femurs are better looking for girls
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FormerKidd

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In terms of health, longer femurs are better.  (There's a study that's been linked elsewhere on this forum that studied people outside these ratios and found correlations between certain late-life issues and longer tibias.)
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Bruce Wayne

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I think the Tibia mockup will always look better because longer tibias look really good on men whereas longer femurs are better looking for girls

It's not just "good". More like the difference between "normal" and "freak".

In terms of health, longer femurs are better.  (There's a study that's been linked elsewhere on this forum that studied people outside these ratios and found correlations between certain late-life issues and longer tibias.)

We live shorter with tibia lengthening? Did the study mean people born with long tibias or people who lengthen tibias?
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Johnson1111

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It's not just "good". More like the difference between "normal" and "freak".

We live shorter with tibia lengthening? Did the study mean people born with long tibias or people who lengthen tibias?

If someone’s femur and tibia ratio is normal, is something like 6cm in the femur enough to throw them out of the normal range? Or is it just in our head because we are judging ourselves too hard?
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Bruce Wayne

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If someone’s femur and tibia ratio is normal, is something like 6cm in the femur enough to throw them out of the normal range? Or is it just in our head because we are judging ourselves too hard?

No, I'm pretty convinced now that it's the femur one isn't normal.

Here's a quote that I found: "The femur/ tibia percentage ratio from individual to individual normally falls from 52:48 UP to 56:44."

That's 0.92 to 0.78. So 0.7 ratio is not normal when 0.9 is still on the height end of normal range.
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myloginacc

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No, I'm pretty convinced now that it's the femur one isn't normal.

Here's a quote that I found: "The femur/ tibia percentage ratio from individual to individual normally falls from 52:48 UP to 56:44."

That's 0.92 to 0.78. So 0.7 ratio is not normal when 0.9 is still on the height end of normal range.

So what were your (estimated) bone measurements again? Tibias, femurs, and t/f ratio?
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Yes I do want to add, before doing this surgery, ask yourself if you have optimized your life to the fullest extent possible (job/career, personality, etc).

Bruce Wayne

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So what were your (estimated) bone measurements again? Tibias, femurs, and t/f ratio?

About 46 : 37. I measured it manually, so could be not very accurate.
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Purushrottam

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I think myloginacct posted a study that showed that the risk of arthiritis is higher if the tibia to femur ratio deviates too high from 0.8. That study suggested that bias should be towards lengthening the femur over the tibia.
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myloginacc

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About 46 : 37. I measured it manually, so could be not very accurate.

Yeah, probably not perfect measurements. I'm assuming 46cm for femurs and 37cm for tibias.

Still, those measurements give you a 0.804 t/f ratio. That's super normal, at least according to that study. The average deviation is +/- 0.03 from 0.80. Thus, a normal/average T/F ratio, according to the study, is 0.77~0.83.

Going with the quoted "safe figures" in the forums... 5cm on tibias, and 6.5cm on femurs... If you actually did both segments, that'd give you a 0.80 ratio. If you did 5cm+5cm, you'd end up at 0.82. If you did 5cm tibias, 8cm femurs, you'd end up at 0.77. All average according to the study.

On the other hand, if you were lengthening only one segment, you could only lengthen your femurs by... 2cm... to keep within what the study shows as the lower end average for T/F ratio (0.770). For tibias, you could only lengthen them by 1.2cm to keep a normal/average t/f ratio (it'd go up to 0.830). 1.6cm would give you 0.839, the limit at 0.83.
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Yes I do want to add, before doing this surgery, ask yourself if you have optimized your life to the fullest extent possible (job/career, personality, etc).

myloginacc

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I think myloginacct posted a study that showed that the risk of arthiritis is higher if the tibia to femur ratio deviates too high from 0.8. That study suggested that bias should be towards lengthening the femur over the tibia.

Yep:

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Increasing tibia length relative to femur length was found to be a significant predictor of ipsilateral hip and knee arthritis. Therefore, we recommend that when performing limb lengthening, surgical planning should lean toward recreating the normal ratio of 0.80. In circumstances where one bone is to be overlengthened relative to the other, bias should be toward overlengthening the femur. This same principle can be applied to limb-reduction surgery, where in certain circumstances, one may choose to preferentially shorten the tibia.
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Yes I do want to add, before doing this surgery, ask yourself if you have optimized your life to the fullest extent possible (job/career, personality, etc).

Bruce Wayne

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Yeah, probably not perfect measurements. I'm assuming 46cm for femurs and 37cm for tibias.

Still, those measurements give you a 0.804 t/f ratio. That's super normal, at least according to that study. The average deviation is +/- 0.03 from 0.80. Thus, a normal/average T/F ratio, according to the study, is 0.77~0.83.

Going with the quoted "safe figures" in the forums... 5cm on tibias, and 6.5cm on femurs... If you actually did both segments, that'd give you a 0.80 ratio. If you did 5cm+5cm, you'd end up at 0.82. If you did 5cm tibias, 8cm femurs, you'd end up at 0.77. All average according to the study.

On the other hand, if you were lengthening only one segment, you could only lengthen your femurs by... 2cm... to keep within what the study shows as the lower end average for T/F ratio (0.770). For tibias, you could only lengthen them by 1.2cm to keep a normal/average t/f ratio (it'd go up to 0.830). 1.6cm would give you 0.839, the limit at 0.83.

According to this older post: http://www.makemetaller .org/index.php?topic=293.0, it could be up to 52:48. Probably your study just means average range instead of normal range which is difference. For example, a 5'1" man is well below the average height of man of 5'10" but he's not abnormal either because there are many men who are born 5'1". But 4' man is another story.
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Starting height : 167cm | Goal : 172cm | Dr. Giotikas

"My anger outweighs my guilt."

myloginacc

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According to this older post: http://www.makemetaller .org/index.php?topic=293.0, it could be up to 52:48. Probably your study just means average range instead of normal range which is difference. For example, a 5'1" man is well below the average height of man of 5'10" but he's not abnormal either because there are many men who are born 5'1". But 4' man is another story.

Your figures use percentage. 52% femurs and 48% tibias, and 56% femurs and 44% tibias.

Starting from your original (83cm) total leg length:

.56*83 = 46.48
.44*83 = 36.52

36.52/46.48 = 0.78.

.52*83 = 43.16
.48*83 = 39.89

39.89/43.16 = 0.92.

This is the supposed natural range your t/f ratios could have been. Indeed, your femurs are on the longer side of the spectrum according to M M T (0.804, closer to 0.78 - or 56% femurs). Whereas the ratio is almost perfect according to the study.

If you increased your height by 5cm (37cm tibias; 46cm femurs): tibias would give you a 0.91 t/f ratio (supposedly normal given the old forums' ratios). 5cm on femurs would give you a 0.72 t/f ratio (deviating from both the M M T post and the study). This almost seems too good for tibias, and anathema to the anecdotal evidence of femoral vs tibial patients posted here.

I'm not calling bs on the ratios from that post because human proportions vary. Black men have shorter trunks, longer legs (specially tibias) and longer forearms compared to white men of the same height. However, one figure is from a study which examined a cadaveric osteological collection, not written by doctors involved in cosmetic LL (JPO), and which evaluated correlation between t/f and osteoarthritis through multiple regression analysis. The other is by a former admin of the previous forum, a place involved in collusion scandals with CLL doctors, specially getting them to do external tibias in places like India. It may be because I don't have an account on the old forums, but I can't find the source for the ranges he posted and termed as the "normal range" of femur:tibia ratios.

The main counterargument you can use against the study is that it comes from the JPO - the Journal of Pediatric Orthopedics, which is under the umbrella of POSNA - the Pedriatic Orthopedic Society of North America.

However, the Hamann-Todd osteological collection doesn't seem to even focus towards infant and adolescent bone collections:

http://www.oberlinlibstaff.com/omeka_projects/exhibits/show/ohio-bones/the-hamann-todd-osteological-c
https://www.cmnh.org/phys-anthro/collection-database
https://en.wikipedia.org/wiki/Cleveland_Museum_of_Natural_History

Quote
Hamann-Todd Human Osteological Collection

This collection contains more than 3,000 cadaver-derived human skeletons collected by Carl A. Hamann and T. Wingate Todd between 1912 and 1938. Superb documentation makes this the world’s largest documented collection of modern human skeletal remains.
 
The Hamann-Todd Human Osteological Collection is accessible for legitimate research and study by qualified investigators. Access is free for non-commercial use.
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Yes I do want to add, before doing this surgery, ask yourself if you have optimized your life to the fullest extent possible (job/career, personality, etc).

Bruce Wayne

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Your figures use percentage. 52% femurs and 48% tibias, and 56% femurs and 44% tibias.

Starting from your original (83cm) total leg length:

.56*83 = 46.48
.44*83 = 36.52

36.52/46.48 = 0.78.

.52*83 = 43.16
.48*83 = 39.89

39.89/43.16 = 0.92.

This is the supposed natural range your t/f ratios could have been. Indeed, your femurs are on the longer side of the spectrum according to M M T (0.804, closer to 0.78 - or 56% femurs). Whereas the ratio is almost perfect according to the study.

If you increased your height by 5cm (37cm tibias; 46cm femurs): tibias would give you a 0.91 t/f ratio (supposedly normal given the old forums' ratios). 5cm on femurs would give you a 0.72 t/f ratio (deviating from both the M M T post and the study). This almost seems too good for tibias, and anathema to the anecdotal evidence of femoral vs tibial patients posted here.

I'm not calling bs on the ratios from that post because human proportions vary. Black men have shorter trunks, longer legs (specially tibias) and longer forearms compared to white men of the same height. However, one figure is from a study which examined a cadaveric osteological collection, not written by doctors involved in cosmetic LL (JPO), and which evaluated correlation between t/f and osteoarthritis through multiple regression analysis. The other is by a former admin of the previous forum, a place involved in collusion scandals with CLL doctors, specially getting them to do external tibias in places like India. It may be because I don't have an account on the old forums, but I can't find the source for the ranges he posted and termed as the "normal range" of femur:tibia ratios.

The main counterargument you can use against the study is that it comes from the JPO - the Journal of Pediatric Orthopedics, which is under the umbrella of POSNA - the Pedriatic Orthopedic Society of North America.

However, the Hamann-Todd osteological collection doesn't seem to even focus towards infant and adolescent bone collections:

http://www.oberlinlibstaff.com/omeka_projects/exhibits/show/ohio-bones/the-hamann-todd-osteological-c
https://www.cmnh.org/phys-anthro/collection-database
https://en.wikipedia.org/wiki/Cleveland_Museum_of_Natural_History

Yeah, I also thought that with 5cm on tibia, I'd still fall into normal range according to the old forum while it wouldn't be the case with femur lengthening. Eventhough, I was wondering how they came up with that number too. But your study actually mentioned the average and not the normal range.

In the end, based on my mockups, I look more normal with the 5cm tibias.
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25 years 4 months | Pre-CLL

Starting height : 167cm | Goal : 172cm | Dr. Giotikas

"My anger outweighs my guilt."
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