Robot-assisted Total Knee Replacement Surgery And Its Key Visual Analysis

With the development of the computer technology and the robotics, the robot assisted surgical technology is paid more attention to by more and more people. Some applied surgical systems are appeared, which do not relate to the surgical system for total knee replacement. However, thousands of patients suffering from the joint disabilities such as rheumatoid arthritis and osteoarthritis go under the total knee replacement (TKR) surgery in order to reactivate themselves and ease the pain. The performance of TKR mostly lies on the precision of position and prosthetic components fixing. Presently, the positioning of the jig-based TKR system, which influences the quality of TKR, depends on clinic experience, and there are many kinds of jig systems that are difficult in operation. The precision of prosthetic components fixing and the healing of patients are also influenced by jig systems.Classical robot assisted surgical systems have the disadvantages of unideal positioning precision and hard initial location, which are always the research hot spots. Based on the concept of robot integrated surgery, we have used the term RASSTKR (Robot Assisted Surgical System for Total Knee Replacement). The key technologies of RASSTKR such as system construction, positioning and calibration are studied on either theory or application in this paper. The main research work is as follows:Considering repetitions and economy profit, it is not economical to developing a special surgical system. So how to develop similar surgical systems such as total hip replacement and neurosurgery based on RASSTKR and design the interface with these surgeries will be an important task. Based on the characteristics of RASSTKR, the extend conception modal of RASSTKR is established to provide the theoretical basis and technological support.Positioning technology is one of the key technologies of RASSTKR. In this paper, the positioning model of RASSTKR is introduced, after describing its construction and algorithm flow. Combining the computer vision theory and the knee physiological feature, we present a new method of femoral positioning which provide the directtheoretical ensurence for the operations.Calibration technologies including probe calibration, camera calibration and hand/eye calibration are also discussed in this paper. The new point calibration of probe is presented in detail in the part of probe calibration. In the part of camera calibration, the method of camera calibration and the principle of stereo calibration are discussed. For the key calibration technology in hand-eye RASSTKR—hand/eye calibration, the traditional hand/eye calibration conception and method are summarized in brief. According to the stereo system in RASSTKR, a new method of hand/eye calibration for stereo system are proposed by taking full advantage of the relationship between camera and robot hand.Having applied the above technologies in RASSTKR into application, the team led by Prof.Liu Yuncai in Shnaghai JiaoTong University establishes the first real RASSTKR system (WATO) in our country. (I finished this paper in the team.) For the WATO system, its system module construction is summarized in detail, which provides compressive theoretical summary and application experience for the further research in the clinic surgery.