Three‐dimensional shape variation of talar surface morphology in hominoid primates

Abstract

The hominoid foot is of particular interest to biological anthropologists, as changes in its anatomy through time reflect the adoption of terrestrial locomotion, particularly in species of Australopithecus and Homo. Understanding the osteological morphology associated with changes in whole foot function and the development of the plantar medial longitudinal foot arch are key to understanding the transition through habitual bipedalism in australopithecines to obligate bipedalism and long-distance running in Homo. The talus is ideal for studying relationships between morphology and function in this context, as it is a major contributor to the adduction-abduction, plantar-dorsal flexion and inversion-eversion of the foot, and transmits all forces encountered from the foot to the leg. The talar surface is predominantly covered by articular facets, which have different quantifiable morphological characters, including surface area, surface curvature and orientation. The talus also presents challenges to the investigator, as its globular shape is very difficult to quantify accurately and reproducibly. Here we apply a three-dimensional approach using type 3 landmarks (slid semilandmarks) that are geometrically homologous to determine overall talar shape variations in a range of living and fossil hominoid taxa. Additionally, we use novel approaches to quantify the relative orientations and curvatures of talar articular facets by determining the principal vectors of facet orientation and fitting spheres to articular facets. The resulting metrics are analysed using phylogenetic regressions and principal components analyses. Our results suggest that articular surface curvatures reflect locomotor specialisations with, in particular, orangutans having more highly curved facets in all but the calcaneal facet. Similarly, our approach to quantifying articular facet orientation appears to be effective in discriminating between extant hominoid species, and may therefore provide a sound basis for the study of fossil taxa and evolution of bipedalism in Australopithecus and Homo.

Multivariate analysis of variations in intrinsic foot musculature among hominoids

“…; Proctor, ; Parr et al. ). These approaches may also be effective for obtaining a better insight into an evolutionary context of the hominoid foot musculature because locomotor capabilities are determined by the structure and function of both the skeletal and muscular systems.…”

“…Based on comparative anatomical analyses between humans and great apes, anthropologists and morphologists have discussed form-function relationships in the hindlimb and the evolution of human bipedal locomotion (e.g. Morton, 1924;Straus, 1930;Schultz, 1963;Tuttle, 1970;Ishida, 1972;Bojsen-Møller, 1979;Lewis, 1980a,b;Gomberg, 1981Gomberg, , 1985Rose, 1988;Aiello & Dean, 1990; Thorpe et al 1999;Marchi, 2005Marchi, , 2010Vereecke et al 2005;Klenerman & Wood, 2006;Payne et al 2006;Lovejoy et al 2009;Kanamoto et al 2011;Myatt et al 2011;Ward et al 2011;Zipfel et al 2011;Proctor, 2013;Parr et al 2014).…”

“…Consequently, such techniques have been widely applied in physical anthropology to characterize morphological variations of foot bones (e.g. Kanamoto et al 2011;Zipfel et al 2011;Proctor, 2013;Parr et al 2014). These approaches may also be effective for obtaining a better insight into an evolutionary context of the hominoid foot musculature because locomotor capabilities are determined by the structure and function of both the skeletal and muscular systems.…”

Elevated Lip Liner Positions Improving Stability in Total Hip Arthroplasty – An Experimental Study

“…The acetabular component was positioned with 40 degrees of abduction and 30 degrees of anteversion as this is the ideal acetabular cup position suggested by Scheerlinck [22]. We also acknowledge that there is significant variability in this range and the formerly described Lewinnek 'safe zones' have since been shown to vary based on the dynamics of the patient as well as the pelvis position in the sagittal plane changes throughout different stance positions and functional activities [23,24].…”

A Virtual geometric morphometric approach to the quantification of long bone bilateral asymmetry and cross‐sectional shape

“…GMM methods are based on two-or three-dimensional (2D or 3D) landmark configurations (Bookstein, 1991), and these are analyzed in a way that preserves their geometry to allow for the statistical appraisal of shapes or forms (see Mitteroecker and Gunz, 2009). The GMM tool kit has been used widely to quantify bone shape (Bastir et al, 2011(Bastir et al, , 2014Cardini and Loy, 2013;Parr et al, 2014;Wilson and Werneburg, 2014), reflecting the power and flexibility of those methods (Adams et al, 2013).…”