Speedy skeletal prototype production to help diagnosis in orthopaedic and trauma surgery. Methodology and examples of clinical applications.

As a medical imaging complement, a real 3D replica of the anatomical area of interest can be of substantial advantage in orthopaedic and trauma surgery. Unlike the 3D virtual, it makes palpable the notion of scale and volume, and apparent hidden or ambiguous details and thus enhance or facilitate the diagnosis and eventual surgical solutions. CT data of patients, in DICOM3 standard, were used for digital 3D reconstruction followed by rapid prototyping (fused deposition modelling) of acrylonitrile-butadiene-styrene (ABS) replicas of the areas of interest. Three applications were realized: osteotomy for epiphyseal malunion, shoulder arthroplasty and femoral trochleoplasty. The actual size replicas (obtained in less than thirty hours) provided excellent spatial representation with estimation of available bone stock and materialization of relief. The process has proven to be appropriate (and economically reasonable), including for common cases, when it comes to complex spatial geometry and objective representation of the scale of volumes.