The group statistics (MEAN±SD) of the morphological characteristics of the calcaneus based on landmark distances.

<p>Abbreviations: the length of the calcaneal axis (LCA), the height of the posterior facet (HPF), the length of the posterior facet (LPF), the length of the anterior process (LAP), the height of the anterior process (HAP), the critical angle of Gissane (GA), the tuber angle of Böhler (BA).</p><p>The group statistics (MEAN±SD) of the morphological characteristics of the calcaneus based on landmark distances.</p

Correlation between the SPHARM coefficients of the left and the right calcaneus.

<p>Linear correlation is performed on the reduced set of coefficients excluding the three highest coefficients (see inset).</p

An example of reconstructed SSM of right calcaneus using the whole set of 144 spherical harmonic coefficients (left) and the reduced set of 41 representative coefficients (right).

<p>An example of reconstructed SSM of right calcaneus using the whole set of 144 spherical harmonic coefficients (left) and the reduced set of 41 representative coefficients (right).</p

An example of reconstructed SSM of right calcaneus using (from left to right) the 25th, 50th and 75th quartile of the spherical harmonic coefficients.

<p>An example of reconstructed SSM of right calcaneus using (from left to right) the 25th, 50th and 75th quartile of the spherical harmonic coefficients.</p

The mean values of SPHARM estimates of calcaneus (the first 25 coefficients) for the group of 18 right (dark gray) and 18 left (light grey) calcanei.

<p>Error bars indicate one standard deviation.</p

The statistics of SPHARM estimates (box-plots) of calcaneus (the first 25 coefficients) for the group of 18 left (top) and 18 right calcanei (bottom).

<p>Crosses indicate outliers.</p

Statistical, Morphometric, Anatomical Shape Model (Atlas) of Calcaneus

<div><p>The aim was to develop a morphometric and anatomically accurate atlas (statistical shape model) of calcaneus. The model is based on 18 left foot and 18 right foot computed tomography studies of 28 male individuals aged from 17 to 62 years, with no known foot pathology. A procedure for automatic atlas included extraction and identification of common features, averaging feature position, obtaining mean geometry, mathematical shape description and variability analysis. Expert manual assistance was included for the model to fulfil the accuracy sought by medical professionals. The proposed for the first time statistical shape model of the calcaneus could be of value in many orthopaedic applications including providing support in diagnosing pathological lesions, pre-operative planning, classification and treatment of calcaneus fractures as well as for the development of future implant procedures.</p></div

The process of building the morphometric and anatomical atlas of calcaneus.

<p>Hand icon denotes manual or semi-manual assisted processing lead by an experienced operator. Arrows icon denotes two isometric operations (translation and rotation) of the shape. Steps A to H are described in detail Section 2B.</p

Additional file 1 of Statistical shape models of cuboid, navicular and talus bones

SPHARM coefficients for calcaneus, cuboid, navicular and talus bones. (XLS 127 KB