3D visualisation of individual image data

		Markers configuration on the lower limb Markers and model in stand-up calibration posture after fine-tuning registration Woman suject motion capture, markers labelling and model animation mapping Large hip range of motion visualisation (abduction/adduction) Patient body including hip joint visualisation during walking

Pre-operative assessment is the first step for an efficient surgical planning. The 3D motion of the individual hip visualisation and simulation in a virtual reality framework will allow the surgeon to obtain a first diagnostic on the patient's hip. This visualisation is obtained here from MRI and motion capture.

The individual anatomical models of the subject are reconstructed from individual medical images (MRI) while the trajectories of the skin markers that are attached to the subject can as well be obtained from MRI. The reconstructed hip joint is inserted in a virtual human generated from adaptation of a generic model according to manual measurements of the subject's segments. In order to position correctly the hip in the body for a more realistic animation of the model, the hip joint centre is calculated using a technical method detailed in [Kang et al 2003]. An optimised marker configuration is chosen based on the criteria of markers displacements due to skin artefacts. External movements are recorded using this configuration with a Mocap system. Unlike MRI scanner, the optical system allows the recording of large range motions as shown. The positions of optical markers are visualised at the same time as the model during its animation. These recorded markers trajectories are converted into the joint space parameters of the subject's model taking into account the geometry of the skeleton model.

The virtual individualised body of the subject including bones and joint motion can then be visualised in real-time into VHD++, a middleware framework implemented for the simulation and visualisation of virtual humans.