How does the relative wall thickness of human femora follow the biomechanical optima? An experimental study on mummies

Sándor Évinger, Bence Suhai, B. Bernáth, Balázs Gerics, Ildikó Pap, Gábor Horváth

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We studied how the ratio (K) of the internal:external diameter of human femora follows the biomechanical optima derived earlier by other researchers for marrow-filled tubular bones with circular cross section and minimum mass designed to withstand yield and fatigue, or stiffness, or bending fracture, or impact strengths. With evaluation of radiographs of 107 femora from 57 human mummies the values of K were measured. We found that Aposterior=0. 498±0.085 for the posterior radiographic view, and Kmedial=0. 589±0.070 for the medial view with Kmin=0.345 and K max=0.783. The theoretical optima for K depend on the ratio (Q) of the marrow:bone density. Accepting the assumption of earlier authors that Q=0.50, our data show that human femora are optimised to withstand bending fracture, or yield and fatigue strengths. There were no sex-, age- and length-specific differences in K, and the means of K of the right and left femora of individuals were statistically not significantly different. The biomechanical optimization for K of human femora is not finely tuned. Compared with fox femora, K of human femora follows the biomechanical optimum to a much lesser extent. Although the relative wall thickness W=1-K of human femora are optimised, the very low relative mass increment due to deviation of K from the optimum and the considerable intraspecific variance of K make it probable that an accurate optimization of the relative wall thickness is irrelevant in humans.

Original languageEnglish
Pages (from-to)899-905
Number of pages7
JournalJournal of Experimental Biology
Volume208
Issue number5
DOIs
Publication statusPublished - Mar 2005

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Mummies
femur
fatigue
Femur
bone
experimental study
stiffness
cross section
Fatigue
fatigue strength
Bone Marrow
bone density
foxes
Bone Density
researchers
Research Personnel
bones
Bone and Bones

Keywords

  • Bone mechanics
  • Human femora
  • Marrow-filled tubular bones
  • Mummies
  • Optimum bone-wall thickness

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Agricultural and Biological Sciences (miscellaneous)

Cite this

How does the relative wall thickness of human femora follow the biomechanical optima? An experimental study on mummies. / Évinger, Sándor; Suhai, Bence; Bernáth, B.; Gerics, Balázs; Pap, Ildikó; Horváth, Gábor.

In: Journal of Experimental Biology, Vol. 208, No. 5, 03.2005, p. 899-905.

Research output: Contribution to journalArticle

Évinger, Sándor ; Suhai, Bence ; Bernáth, B. ; Gerics, Balázs ; Pap, Ildikó ; Horváth, Gábor. / How does the relative wall thickness of human femora follow the biomechanical optima? An experimental study on mummies. In: Journal of Experimental Biology. 2005 ; Vol. 208, No. 5. pp. 899-905.
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