Three-dimensional imaging in orthopaedic surgery: a radiologist's viewpoint

Since the profound changes in medical science brought about by the advent of digitized imaging (ultrasonography, CT scan, MRI), the 3D imaging born from these acquisition systems has progressively developed and its applications are being more and more widely used in orthopaedics and traumatology. Because of the value of multiplanar reconstructions and because they can be obtained in real time with most software, they have become the usual complement to the 2D data presented to the clinicians. 3D images which render surface and volume visible are easily generated and give the surgeon an overall view of the lesion as it will be revealed during the procedure. The most interesting perspectives are those which will make 3D imaging a truly therapeutic tool. Three-dimensional systems using anatomical contour extraction open the way to simulated surgical procedures, virtual manipulation of bony parts, anatomical modelling and customized prostheses. Surgical procedures and computer-assisted radiotherapy based on 3D images are becoming more widespread. Lastly, 3D imaging by finite elements makes possible the stress simulations which are of particular interest in many orthopaedic disorders.