Three-dimensional osteometric scaling and normative modelling of skeletal segments.

Many analytical biomechanics methods require extensive three-dimensional descriptions of anatomical geometry. In particular, researchers requiring the three-dimensional coordinates of specific boney landmarks (e.g. tendon and ligament attachments) are often forced to extrapolate such measurements from an experimental specimen set to their subject geometry. This work offers an approach to two problems inherent above; accurate extrapolation of specimen landmark locations to subject homologues and statistical accumulation of normative three-dimensional anatomical landmark data bases. A least squares solution for an affine scaling transformation from specimen to subject is used which incorporates both right-left and same hand comparisons. A two stage technique is formulated to consecutively remove landmark location variation and to size a normative specimen from a set of similar specimens. This ability to statistically represent a specimen set will provide better geometric models for other analytical studies and prosthetic design and evaluation.