Bone drilling haptic interaction for orthopedic surgical simulator.

Drilling procedure is widely used in orthopedic surgery to position reduced fractured bones and prosthetic components. However, successful execution of bone drilling requires a high level of dexterity and experience, because the drilling resistance is large and sometimes vibrates violently to difficultly grasp the hand-piece or even break the slender drill. This paper introduces haptic functions that are added to a volume based surgical simulator to simulate the drilling process. These haptic functions compute drilling forces and torques based on reliable metal removing theorem. Therefore, accurate prediction for the drilling process can be obtained to provide effective surgery training and rehearsal. A simulation example of screw and plate surgery for positioning the hip trochanter fracture illustrates the practicality and versatility of the proposed method.

Automatic spinal disease diagnoses assisted by 3D unaligned transverse CT slices.

This paper describes a three-dimensional (3D) reconstruction method and an automatic diagnosis method for spinal diseases using unaligned transverse slices that have arbitrary angles and intervals but do not intersect to each other at regions of interest. The 3D reconstruction method extends the marching cube algorithm to generate triangulated isosurfaces for these unaligned slices. The automatic spinal disease diagnostic method analyses boundaries of discs and vertebral bodies on unaligned transverse slices to estimate the presence and extent of disc herniation and canal compression, and deformities in the spinal curve. The prototype system can be used as a qualitative and quantitative tool for the diagnosis of various spinal diseases using unaligned transverse slices.