Surgeon's Movements Research Articles

Recording the direct surgeon's view with an operating microscopic view improves microscopic ophthalmic surgery training.

To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope, which lacks information on the movement and position of the surgeon's hands, and to facilitate the reproduction of a skilled surgeon's technique by a surgeon in training. A small camera was attached to the operating microscope with a custom adapter. Microscopic surgeon's view and direct surgeon's view through this new camera were recorded in the surgical recording system. Both movies were synchronized and analyzed how do surgeons handle the instruments. A small camera attached to the operating microscope allowed the surgeon's hands motion to be recorded without interfering with the surgeon's movements. Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device. Even in the simple paracentesis procedure, different surgeons used different methods. Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view. Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries.

Dynamic Multiaction Recognition and Expert Movement Mapping for Closed Pelvic Reduction

Pelvic fractures are one of the most serious traumas in orthopedic care, and reduction during routine surgery is a significant challenge. Because there are so many vital organs, blood vessels, and nerves around the pelvis, and the reduction force is large, the operational requirements for the surgeon are extremely strict and require extensive experience and surgical skills. This paper proposes a method for collecting and digitizing doctors' reduction movements, which aims to help intelligent devices recognize surgeons' reduction actions and provides a means to learn from expert experience to improve the accuracy of surgery. First, the Conv-BiLSTM algorithm with multilayer cross-fused features is proposed. It extracts time and spatial correlations between multimodal data in a hierarchical manner. Second, discrete dynamic motion primitives (DMPs) are adopted for mapping the surgeon's palm movement trajectory. Finally, this paper constructs a data acquisition platform and collects data from surgeons with varying proficiency in closed reduction. Experiment results show that the closed reduction action recognition accuracy is 99% and posture recognition accuracy is 95.5%. The recognition algorithm proposed by this paper is significantly higher than the commonly used algorithms in terms of Accuracy, Precision, Recall, and F1-Score. This work provides methods and means for the digitization of surgical expertise and transfers learning for robot-assisted surgery.

Robotics in thoracic surgery

The increasing diffusion of the robotic-assisted technique in thoracic surgery (RATS) in Germany was initially delayed in comparison with other countries. Therefore, there is a large potential to implement the volume of the surgical procedures performed by RATS.The RATS-technique has many positive aspects. For example, the angulated instruments allow a full wristed dexterity like the human hand, but with a greater range of motion. The surgical Robot has a tremor filter and replicates perfectly the surgeon's movements. Furthermore, the 3D-scope enables an image magnification up to 10 times compared to the normal thoracoscopes. The RATS has also some disadvantages. For example, the operating surgeon sits far away from the patient and is not sterile while performing surgery. This is an important factor in in case of emergency situations, like major bleeding, which often require a conversion to thoracotomy.All robotic systems are built after the same master-slave technology, that allows the operating surgeon to have full control of the master system. The slave system consists of mechanical actuators that respond to the master system's inputs, so the surgical robot will translate every single movement of the surgeon at the console.The main surgical indications for RATS are: mediastinal tumors, diaphragm plication and anatomical lung resection like segment resections, lobectomies or sleeve resections.In the future, the implementation of virtual and augmented reality is expected in the training but also in the planning of RATS-operations.

An Image Information-Based Objective Assessment Method of Technical Manipulation Skills for Intravascular Interventions.

The clinical success of vascular interventional surgery relies heavily on a surgeon's catheter/guidewire manipulation skills and strategies. An objective and accurate assessment method plays a critical role in evaluating the surgeon's technical manipulation skill level. Most of the existing evaluation methods incorporate the use of information technology to find more objective assessment models based on various metrics. However, in these models, sensors are often attached to the surgeon's hands or to interventional devices for data collection, which constrains the surgeon's operational movements or exerts an influence on the motion trajectory of interventional devices. In this paper, an image information-based assessment method is proposed for the evaluation of the surgeon's manipulation skills without the requirement of attaching sensors to the surgeon or catheters/guidewires. Surgeons are allowed to use their natural bedside manipulation skills during the data collection process. Their manipulation features during different catheterization tasks are derived from the motion analysis of the catheter/guidewire in video sequences. Notably, data relating to the number of speed peaks, slope variations, and the number of collisions are included in the assessment. Furthermore, the contact forces, resulting from interactions between the catheter/guidewire and the vascular model, are sensed by a 6-DoF F/T sensor. A support vector machine (SVM) classification framework is developed to discriminate the surgeon's catheterization skill levels. The experimental results demonstrate that the proposed SVM-based assessment method can obtain an accuracy of 97.02% to distinguish between the expert and novice manipulations, which is higher than that of other existing research achievements. The proposed method has great potential to facilitate skill assessment and training of novice surgeons in vascular interventional surgery.

Non-Contact VITAL Signs Monitoring of a Patient Lying on Surgical Bed Using Beamforming FMCW Radar.

Respiration and heartrates are important information for surgery. When the vital signs of the patient lying prone are monitored using radar installed on the back of the surgical bed, the surgeon's movements reduce the accuracy of these monitored vital signs. This study proposes a method for enhancing the monitored vital sign accuracies of a patient lying on a surgical bed using a 60 GHz frequency modulated continuous wave (FMCW) radar system with beamforming. The vital sign accuracies were enhanced by applying a fast Fourier transform (FFT) for range and beamforming which suppress the noise generated at different ranges and angles from the patient's position. The experiment was performed for a patient lying on a surgical bed with or without surgeon. Comparing a continuous-wave (CW) Doppler radar, the FMCW radar with beamforming improved almost 22 dB of signal-to-interference and noise ratio (SINR) for vital signals. More than 90% accuracy of monitoring respiration and heartrates was achieved even though the surgeon was located next to the patient as an interferer. It was analyzed using a proposed vital signal model included in the radar IF equation.

"Stand-up straight!": human pose estimation to evaluate postural skills during orthopedic surgery simulations.

Surgery simulators can be used to learn technical and non-technical skills and, to analyse posture. Ergonomic skill can be automatically detected with a Human Pose Estimation algorithm to help improve the surgeon's work quality. The objective of this study was to analyse the postural behaviour of surgeons and identify expertise-dependent movements. Our hypothesis was that hesitation and the occurrence of surgical instruments interfering with movement (defined as interfering movements) decrease with expertise. Sixty surgeons with three expertise levels (novice, intermediate, and expert) were recruited. During a training session using an arthroscopic simulator, each participant's movements were video-recorded with an RGB camera. A modified OpenPose algorithm was used to detect the surgeon's joints. The detection frequency of each joint in a specific area was visualized with a heatmap-like approach and used to calculate a mobility score. This analysis allowed quantifying surgical movements. Overall, the mean mobility score was 0.823, 0.816, and 0.820 for novice, intermediate and expert surgeons, respectively. The mobility score alone was not enough to identify postural behaviour differences. A visual analysis of each participants' movements highlighted expertise-dependent interfering movements. Video-recording and analysis of surgeon's movements are a non-invasive approach to obtain quantitative and qualitative ergonomic information in order to provide feedback during training. Our findings suggest that the interfering movements do not decrease with expertise but differ in function of the surgeon's level.

Comanipulation Robotic Platform for Spine Surgery With Exteroceptive Visual Coupling: Development and Experimentation

Abstract In this paper, a novel surgical robotic platform intended to assist surgeons in cervical spine surgery is presented. The purpose of this surgery is to treat the cervical spine instabilities. The surgical procedure requires drilling into specific region of the vertebrae in order to attach spinal implants and thus ensure a normal spacing between each vertebra concerned. In this context, the proposed robotic platform allows to control and restrict the surgeon's movements to a specific drilling direction set by the surgeon. The current platform is composed of a collaborative robot with seven degrees-of-freedom (DoF) equipped with a drilling tool and directly comanipulated by the surgeon. A motion capture system, as an exteroceptive sensor device, provides the robot controller with the movement data of the vertebra to be drilled. Robot Operating System (ROS) framework is used to enable real-time communication between the collaborative robot and the visual exteroceptive device. In addition, an implemented compliance control program allows to enhance the safety aspect of the robotic platform. Indeed, the collaborative robot follows the patient's movements while constraining the tool movements to an optimal trajectory as well as a limited drilling depth selected by the surgeon. The collaborative robot's elbow movements are also restricted by exploiting the null-space in order to avoid collisions with other equipment or the medical team members. Experimental drilling trials have been performed by an orthopedic surgeon to validate the usefulness and different functionalities of the developed robotic platform, and provide that a collaborative robot can comply with a spine surgery procedure. These preliminary tests were performed in a lumbar spine model for which the use of a robotic device is most frequent due to a lower complexity compared to the cervical spine.

The role of eye tracker in teaching video-assisted thoracoscopic surgery: the differences in visual strategies between novice and expert surgeons in thoracoscopic surgery.

BackgroundIn light of continued advances in surgical techniques, it is essential to improve the efficacy of training young thoracic surgeons. Increasingly, the feedback of visual information is believed to be a crucial teaching tool. When surgeons are looking at surgical teaching videos, eye gaze technology can be used to record the gaze movement to examine the stages of information access.MethodsA total of 8 novice surgeons and 8 expert surgeons were recruited to watch an instructional video of surgery while Tobii Pro Fusion was used to recorded their movement trajectory. Another 36 novice surgeons were recruited and divided into two groups. One group watched the video following the trajectory of the senior thoracic surgeons’ eye movements and the other group watched the raw video. All 36 novice surgeons subsequently underwent a post-test which was conducted via a questionnaire.ResultsThe differences in eye fixation patterns and search strategies between novices and experts were assessed using 4 indexes, including total duration of fixation, time to entry saccade, number of saccades, and peak velocity of saccade. The results were compared using independent-sample t-tests and repeated-measures analysis. When experts watched the videos, there was a 67.8% overlap of eye gaze compared to a 51.4% overlap in novices (P≤0.001). The post-test showed that novice surgeons who watched the video marked with the senior thoracic surgeon’s eye movements had a better understanding of the key points of the operation.ConclusionsNovice and expert surgeons have different eye fixation patterns and search strategies when watching videos of thoracoscopic surgery. Watching surgical videos marked with expert eye movement trajectories is conducive to novice surgeons to master operative skills.

C.6 Action-Related Fixation in Microsuturing, a New Gaze Behavior Metric to Differentiate the Level of Expertise

Background: Gaze behavior differences between expert and novice surgeons have been established in previous studies mainly from the general surgery field.Limited information is available about surgeon’s visual attention during microsurgery procedures where surgical microscope is used. Methods: 4 experts and 3 novices performed 37 independent sutures under the surgical microscope.Eye movements of surgeons and scene video of the surgical performance were recorded.Total suturing time and subtask times were compared between level of expertise.We defined three discrete surgical actions and examined eye gaze (fixation) directly related to each of these actions.Fixation duration (measured by total,pre-action,and post-action duration) were compared between expert and novice, over 3 subtasks (piercing, exiting and cutting) and between pre- and post-action phases. Results: Expert surgeons completed the suture with shorter total time than novices.On average,expert displayed longer fixation time than novice.Experts also maintained their visual engagement constantly over the 3 level of subtask in comparison to novices who required a longer fixation time for the challenging subtask (piercing).Experts use longer pre- than post-action fixation, and this pattern is distributed over all three subtasks.This gaze engagement strategy was not shown in novices. Conclusions: The action-related fixation can be used to evaluate microsurgeons’ level of expertise and in surgical education for gaze training.

Neurosurgical performance between experts and trainees: Evidence from drilling task.

Lumbar laminectomy is a common neurosurgery that requires precise manipulation of power drills. We examined the fine movement controls of novice neurosurgeons in drilling tasks and compared its accuracy to expert surgeons' performance. Four experts and three novice neurosurgeons performed a lumbar laminectomy on a three-dimensional printed spine model. Scene video and surgeons' eye movements were recorded. Independent sample t-Tests were conducted on the number of jump, total fixation durations, pre-jump fixation durations, post-jump fixation durations and jump distances over novice and expert surgeons. No statistically significant differences were recorded in terms of total fixations and pre-jump fixation durations. However, novices had more jumping events, greater jump distances and longer post-jump fixation durations when compared to expert neurosurgeons. Differences in movement accuracy and eye measures were found between expert and novice neurosurgeons during a simulated microscopic lumbar laminectomy. A more comprehensive understanding of surgeon's fine movement control mechanism and eye-hand coordination in microsurgery is essential for us before building an enhanced training protocol for surgical residents in neurosurgery.

Laparoscopic choledochal cyst resection using a novel articulating instrument in pediatric patients

Abstract Background Historically, choledochal cyst excision has been performed as an open procedure. Controversy remains regarding managing this technically challenging entity in a minimally invasive fashion. Methods A novel mechanically-designed intuitive, articulating instrument is used to facilitate intracorporeal suturing when there is limited working space. The mechanical design of the three-axis Gimbal cuff facilitates intracorporeal suturing by providing intuitive wristed function to the surgeon by translating the surgeon's wrist movement to the end effector. Results We describe the adoption of a novel articulating instrument to facilitate a primary hepaticoduodenostomy within the limited space of a pediatric porta and a redo hepaticojejunostomy. Conclusions These cases demonstrate the use of a novel articulating needle driver to sew an intracorporeal bilio-enteric anastomosis which obviates the need for robotic technology while expanding a laparoscopic surgeon's armamentarium.

Stereoscopic Near-Infrared Fluorescence Imaging: A Proof of Concept Toward Real-Time Depth Perception in Surgical Robotics.

The increasing use of surgical robotics has provoked the necessity for new medical imaging methods. Many assistive surgical robotic systems influence the surgeon's movements based on a model of constraints and boundaries driven by anatomy. This study aims to demonstrate that Near-Infrared Fluorescence (NIRF) imaging could be applied in surgical applications to provide subsurface mapping of capillaries beneath soft tissue as a method for imaging active constraints. The manufacture of a system for imaging in the near-infrared wavelength range is presented, followed by a description of computational methods for stereo-post-processing and data acquisition and testing used to demonstrate that the proposed methods are viable. The results demonstrate that it is possible to use NIRF for the imaging of a capillary submersed up to 11 mm below a soft tissue phantom, over a range of angles from 0° through 45°. Phantom depth has been measured to an accuracy of ±3 mm and phantom angle to a constant accuracy of ±1.6°. These findings suggest that NIRF could be used for the next generation of medical imaging in surgical robotics and provide a basis for future research into real-time depth perception in the mapping of active constraints.

Is the Human Brain Capable of Controlling Seven Degrees of Freedom?

BackgroundConventional rigid laparoscopic instruments offer five degrees of freedom (DOF). Robotic instruments add two independent DOFs allowing unconstrained directional steering. Several nonrobotic instruments have been developed with the additional DOFs, but with these devices, surgeon's wrist movements are not intuitively transmitted into tip movements. In this study, a new articulated instrument has been evaluated. The aim of the study was to compare learning curves and performances of conventional laparoscopic instruments, the da Vinci system and Steerable devices in a crossover study. Materials and methodsA total of 16 medical students without any laparoscopic experience were trained for 27 h to operate all of a rigid, a robotic, and a new Steerable instrument in a random order. Learning curves and ultimate experience scores were determined for each instrument. Strain in wrist and shoulders was assessed with a visual analog score. ResultsPerforming the suturing task with rigid and robot instruments required 4 h of training, compared with 6 h to master the Steerable instrument. After 9 h of training with each instrument, completing the complex suturing pattern required 662 ± 308 s with rigid instruments, 279 ± 90 s with the da Vinci system, and 279 ± 53 s with the Steerable instrument. Pain scores were significantly higher after using the rigid instruments compared with the Steerable instruments. ConclusionsTransmission of torque and the presence of additional two DOFs in combination with reduced crosstalk significantly improved the instrument dexterity where the Steerable platform is concerned. Although the learning curve is longer, once mastered, it provides enhanced surgical freedom.

The MUSHA underactuated hand for robot-aided minimally invasive surgery.

Keyhole surgery is characterized by loss of dexterity of surgeon's movements because of the limited workspace, nonintuitive motor skills of the surgical systems, and loss of tactile sensation that may lead to tissue damage and bad execution of the tasks. In this paper, a three-fingered underactuated miniature tool for robot-aided laparoscopic surgery is presented. The design is conceived to realize a closed-hand configuration allowing the insertion of the tool into the abdominal cavity through the trocar in one step and to reach different grasping as well as pushing/holding configurations once in the cavity. Aiming to replicate human hand dexterity and versatility, different solutions for the kinematic structure of the hand are analyzed using quality indices to evaluate the manipulability and stability of the grasp. Furthermore, a first prototype of fingertip force sensor based on fiber Bragg grating (FBG) technology has been realized and tested. The design choices of the prototype are described and discussed with the aid of experiments. The whole concept and the need for such anthropomorphic tool are discussed with surgeons to highlight constraints and potentials in surgical tasks. The feedback by expert surgeons is used to provide specifications and improvements to the kinematics and mechanical design. The investigations of different designs allow identifying the optimal solution to improve grasping and manipulation capabilities. The tests on FBG sensors led to the conclusion that this technology guarantees good performance and can be a good solution for applications in surgical robotics.

Gaze gesture based human robot interaction for laparoscopic surgery.

While minimally invasive surgery offers great benefits in terms of reduced patient trauma, bleeding, as well as faster recovery time, it still presents surgeons with major ergonomic challenges. Laparoscopic surgery requires the surgeon to bimanually control surgical instruments during the operation. A dedicated assistant is thus required to manoeuvre the camera, which is often difficult to synchronise with the surgeon's movements. This article introduces a robotic system in which a rigid endoscope held by a robotic arm is controlled via the surgeon's eye movement, thus forgoing the need for a camera assistant. Gaze gestures detected via a series of eye movements are used to convey the surgeon's intention to initiate gaze contingent camera control. Hidden Markov Models (HMMs) are used for real-time gaze gesture recognition, allowing the robotic camera to pan, tilt, and zoom, whilst immune to aberrant or unintentional eye movements. A novel online calibration method for the gaze tracker is proposed, which overcomes calibration drift and simplifies its clinical application. This robotic system has been validated by comprehensive user trials and a detailed analysis performed on usability metrics to assess the performance of the system. The results demonstrate that the surgeons can perform their tasks quicker and more efficiently when compared to the use of a camera assistant or foot switches.

Simple training tricks for mastering and taming bypass procedures in neurosurgery.

Background:Neurosurgeons devoted to bypass neurosurgery or revascularization neurosurgery are becoming scarcer. From a practical point of view, “bypass neurosurgeons” are anastomosis makers, vessels technicians, and time-racing repairers of vessel walls. This requires understanding the key features and hidden tricks of bypass surgery. The goal of this paper is to provide simple and inexpensive tricks for taming the art of bypass neurosurgery. Most of these tricks and materials described can be borrowed, donated, or purchased inexpensively.Methods:We performed a review of relevant training materials and recorded videos for training bypass procedures for 3 years between June 2014 and July 2017. In total, 1,300 training bypass procedures were performed, of which 200 procedures were chosen for this paper.Results:A training laboratory bypass procedures is required to enable a neurosurgeon to develop the necessary skills. The important skills for training bypass procedures gained through meticulous practice to be as reflexes are coordination, speed, agility, flexibility, and reaction time. Bypassing requires synchronization between the surgeon's gross movements, fine motoric skills, and mental strength. The suturing rhythm must be timed in a brain–body–hand fashion.Conclusion:Bypass-training is a critical part of neurosurgical training and not for a selected few. Diligent and meticulous training can enable every neurosurgeon to tame the art of bypass neurosurgery. This requires understanding the key features and hidden tricks of bypass surgery, as well as uncountable hours of training. In bypass neurosurgery, quality and time goes hand in hand.

A Low-Cost, Passive Navigation Training System for Image-Guided Spinal Intervention

Navigation technology is used for training in various medical specialties, not least image-guided spinal interventions. Navigation practice is an important educational component that allows residents to understand how surgical instruments interact with complex anatomy and to learn basic surgical skills such as the tridimensional mental interpretation of bidimensional data. Inexpensive surgical simulators for spinal surgery, however, are lacking. We therefore designed a low-cost spinal surgery simulator (Spine MovDigSys 01) to allow 3-dimensional navigation via 2-dimensional images without altering or limiting the surgeon's natural movement. A training system was developed with ananatomical lumbar model and 2 webcams to passively digitize surgical instruments under MATLAB software control. A proof-of-concept recognition task (vertebral body cannulation) and a pilot test of the system with 12 neuro- and orthopedic surgeons were performed to obtain feedback on the system. Position, orientation, and kinematic variables were determined and the lateral, posteroanterior, and anteroposterior views obtained. The system was tested with a proof-of-concept experimental task. Operator metrics including time of execution (t), intracorporeal length (d), insertion angle (α), average speed (v¯), and acceleration (a) were obtained accurately. These metrics were converted into assessment metrics such as smoothness of operation and linearity of insertion. Results from initial testing are shown and the system advantages and disadvantages described. This low-cost spinal surgery training system digitized the position and orientation of the instruments and allowed image-guided navigation, the generation of metrics, and graphic recording of the instrumental route. Spine MovDigSys 01 is useful for development of basic, noninnate skills and allows the novice apprentice to quickly and economically move beyond the basics.

Low resolution tool tracking for microsurgical training in a simulated environment.

In this work, we propose a method that detects and tracks the tip of tools used in microsurgical training. This method can be used to provide valuable metrics regarding the surgeon's hand movement. It can benefit the training of surgeons, given the steep learning curve in microsurgery. Unlike past research, our tool tracking algorithm does not rely on color based measurements. Thus, it can be used in a broader domain. Also, our approach is robust to surrounding environments with non-static background, where background subtraction techniques are not suitable. Experimental results show that the proposed tool localization method has high accuracy and is statistically reliable.

Objective assessment of robotic surgical skill using instrument contact vibrations.

Surgical skill evaluation ordinarily requires tedious video review and survey completion, while new automatic approaches focus on evaluating the quality of the surgeon's movements in free space. Robotic surgical instrument vibrations are simple to measure and physically correspond to how roughly instruments are handled, but they have yet to be studied as a measure of technical surgical skill. Thirteen surgeons used a robotic surgery system (da Vinci S by Intuitive Surgical) to perform four trials each of peg transfer (PT), needle pass (NP), and intracorporeal suturing (IS). Completion time, instrument vibrations, and applied forces were measured for each trial; root mean square (RMS) and total sum of squares (TSS) were calculated from both the vibration and force recordings. Four experienced surgeons blindly assessed the task videos using a Global Rating Scale (GRS), and skill metrics were compared between the eight novices and five experienced participants. Stepwise regression was performed to predict GRS score from objective skill metrics. The concurrent validity of each metric was evaluated using receiver operating characteristic (ROC) analysis. The GRS demonstrated excellent internal consistency (Cronbach's α = 0.91) and strong inter-rater reliability (ICC = 0.84). Compared to novices, experienced surgeons earned higher GRS scores and performed tasks with lower vibration magnitudes, lower forces, and shorter completion times in 15 of 18 task-metric combinations (p values ranging from 0.042 to <0.001). ROC analysis demonstrated that including vibration and force magnitudes along with completion time in skill prediction models improves the objective classification of subjects as novice or experienced for all tasks studied (PT: 90% sensitivity, 75% specificity; NP: 85% sensitivity, 84% specificity; suturing: 100% sensitivity, 100% specificity). RMS and TSS instrument vibrations are novel construct-valid measures of robotic surgical skill that enable the development of objective skill assessment models comparable to observer-based ratings.

Robotics in the neurosurgical treatment of glioma.

Background:The treatment of glioma remains a significant challenge with high recurrence rates, morbidity, and mortality. Merging image guided robotic technology with microsurgery adds a new dimension as they relate to surgical ergonomics, patient safety, precision, and accuracy.Methods:An image-guided robot, called neuroArm, has been integrated into the neurosurgical operating room, and used to augment the surgical treatment of glioma in 18 patients. A case study illustrates the specialized technical features of a teleoperated robotic system that could well enhance the performance of surgery. Furthermore, unique positional and force information of the bipolar forceps during surgery were recorded and analyzed.Results:The workspace of the bipolar forceps in this robot-assisted glioma resection was found to be 25 × 50 × 50 mm. Maximum values of the force components were 1.37, 1.84, and 2.01 N along x, y, and z axes, respectively. The maximum total force was 2.45 N. The results indicate that the majority of the applied forces were less than 0.6 N.Conclusion:Robotic surgical systems can potentially increase safety and performance of surgical operation via novel features such as virtual fixtures, augmented force feedback, and haptic high-force warning system. The case study using neuroArm robot to resect a glioma, for the first time, showed the positional information of surgeon's hand movement and tool-tissue interaction forces.