The design and evaluation of advanced prosthetic fitting systems requires complex and comprehensive anthropometric data, analysis, and visualization methods. Point-to-point and contact casting measurement methods have been used by prosthetists for many decades. These measurement methods do not provide enough information on the shape, volume and tissue characteristics to allow modern CAD software programs to realistically model the residua for which the socket is being designed. Anatomic three-dimensional reconstruction of the residuum by 3-D Optical Surface and Spiral Computed Tomography (CT) imaging, unlike other 3-D scanning modalities, is capable of clearly delineating the complete surface geometry along with the soft tissue and hard tissue components of the patient's residuum. A true 3-D geometrical description, including the internal tissue characteristics, has therefore become available by noninvasive scanning with low radiation exposure. The goal of this proposal is to interface these modalities to build a finite element model to quantify the prosthetic fitting process. Phase I (measurement validation and development) involves the comparison of four types of measurement methods: the traditional contact method, 3Space hand held point digitizer, 3D Optical Surface digitizer, and Spiral CT volumetric scanner. The last two measurement means allow us to collect high resolution 3-D topological and volumetric data for validation using the 3Space digitizer. Phase II (solid model validation and development) will involve the use of 3D Optical Surface digitizer and spiral CT scanner geometry data to generate a mathematical complete solid model of the residuum with physical mass properties. Both volumetric and internal measurements will be performed on cadaver limbs to validate the solid model's internal and external geometry. With the inclusion of pressure testing (loading) and materials property information, a finite element model will be generated.
