A novel mechatronic tool for computer-assisted arthroscopy

Describes a mechatronic tool for arthroscopy, which is both a smart tool for traditional arthroscopy and the main component of a system for computer-assisted arthroscopy. The mechatronic arthroscope has a cable-actuated servomotor-driven multi-joint mechanical structure, is equipped with a position sensor for measuring the orientation of the tip and a force sensor for detecting possible contact with delicate tissues in the knee, and incorporates an embedded microcontroller for sensor signal processing, motor driving and interfacing with the surgeon and/or the system control unit. The computer-assisted arthroscopy system comprises an image processing module for the segmentation and 3D reconstruction of pre-operative CT or MR images, a registration module for measuring the position of the knee joint, tracking the trajectory of the operating tools and matching pre-operative and intra-operative images, and a human-machine interface that displays the enhanced reality scenario and data from the mechatronic arthroscope in a friendly and intuitive manner. By integrating pre-operative and intra-operative images and information provided by the mechatronic arthroscope, the system allows virtual navigation in the knee joint during the planning phase and computer guidance by augmented reality during the intervention. This paper describes in detail the characteristics of the mechatronic arthroscope and of the system for computer-assisted arthroscopy and discusses experimental results obtained with a preliminary version of the tool and of the system.