A virtual interactive navigation system for orthopaedic surgical interventions

Background and Objective: In the last decade, the field of medicine has ingressed into a new era of technological advancements, driven by an ever increasing demand to reduce patient costs and risks, improve patient safety, efficiency, and surgical outcomes. The need for alternative ways of training and surgery is stronger than ever. Virtual reality based training and surgery systems hold significant promise in this direction. However, development of realistic virtual surgery systems for invasive orthopaedic surgical procedures remains one of the most challenging problems in the field of virtual reality based surgery and training because of the involvement of complex musculoskeletal structures and surgical tools. In recent years, some advances have been made in this area but they have limited practical scope because of their support for small range of procedures and training scenarios. The tools developed so far are either restricted in their ability or follow non patient-centric approaches and hence, cannot be considered viable alternatives to the conventional techniques for invasive orthopaedic surgery and training. In this paper, we discuss the challenges and complexities associated with the development of a virtual reality based system for orthopaedic training and surgery, and present our image guidance based navigation system, developed as part of our ongoing research initiative to build a comprehensive tool for realistic virtual orthopedic surgery and training. Methods: Our image guidance based interactive navigation system provides a common interface for the assembly of different components crucial for a realistic virtual reality based training and surgery application. Presently, the system incorporates various features including rigid body registration, patient-specific three-dimensional model generation, two-dimensional and three-dimensional interactive visualizations, and real time intraoperative surgical guidance. In this paper, we outline the details of our present system along with its key features. Results: A preliminary version of our proposed virtual reality based orthopaedic training and surgery navigation system is presented. To demonstrate the applicability of our system, a sample application showing the anatomically detailed three -dimensional representations of a patient's knee, derived from the pre-operative image scans, along with the corresponding two-dimensional image details is presented. To the best of our knowledge, this is the first attempt that constructs and integrates patient-specific, anatomically correct, and comprehensive three-dimensional models, with all possible soft tissue details, to provide patient-specific visualization and training capabilities. Preliminary feedback by the orthopaedic surgeons on the prototype of our system is very encouraging and pin points some additional features that can further strengthen the efficacy of our tool and its clinical adoption. Conclusion: A comprehensive virtual reality based navigation system for orthopaedic training and surgery is presented. The system utilizes patient-specific two-dimensional image modalities and provides corresponding two-dimensional and three-dimensional, interactive visualization capabilities along with realtime tracking of surgical instruments. The present system can be used as an effective tool for anatomy education, surgical planning, diagnosis, and real-time intra-operative surgical navigation. Additional components such as haptics and real-time tissue deformations are currently under development and will soon be integrated with this platform.