BACKGROUND: Surgical training has been greatly affected by the challenges of reduced training opportunities, shortened working hours, and financial pressures. There is an increased need for the use of training system in developing psychomotor skills of the surgical trainee.AIMS: To develop the training system for fracture fixation and validate its effectiveness in a cohort of junior orthopedic trainees.TRAINING SYSTEM: Computer-navigated training system uses the 2 sets of images from the c-arm while the registration phantom is placed in the fluoroscopic imaging space which permits determination of the position of the x-ray source and the image plane that then guides the trainee to navigate the surgical instruments into the three-dimensional space. No further c-arm exposures are taken during the entire procedure.MATERIAL AND METHODS: The training system was developed to simulate dynamic hip screw fixation. Twelve orthopedic senior house officers performed dynamic hip screw fixation before and after the training on the training system. The results were assessed based on the scoring system that included the amount of time taken, accuracy of guidewire placement, and the number of exposures requested to complete the procedure.RESULTS: The result shows a significant improvement in the amount of time taken, accuracy of fixation, and the number of exposures after the training on the simulator system. The paired student t-test was used and statistically significant results were obtained (p-value < 0.05).CONCLUSION: Computer-navigated training system appears to be a good training tool for young orthopedic trainees. This system can be used to augment training in the operating room and trainees acquire their skills in a "nonthreatening and unhurried environment." The system has the potential to be used in various other orthopedic procedures for learning of technical skills in a manner aimed at ensuring a smooth escalation in task complexity leading to the better performance of procedures in the operating theater. (J Surg 70:304-308. (C) 2013 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)
The Incident Commander plays a vital role in the effectiveness of the UK's Fire and Rescue Services, in tackling fires. The reduction in the number of incidents along with budget cuts is placing an increased emphasis on training. In this paper we pro pose a serious game as areplacement for the tradition training methods for these important command positions, with a discussion of immersion versus more traditional platform.
BACKGROUND: Simulation and surgical training has moved on since its inception during the end of the last century. The trainees are getting more exposed to computers and laboratory training in different subspecialties. More needs to be done in orthopedic simulation in spinal surgery.AIMS: To develop a training system for pedicle screw fixation and validate its effectiveness in a cohort of junior orthopedic trainees.TRAINING SYSTEM: Fully simulated computer-navigated training system is used to train junior orthopedic trainees perform pedide screw insertion in the lumbar spine. Real patient computed tomography scans are used to produce the real-time fluoroscopic images of the lumbar spine.MATERIAL AND METHODS: The training system was developed to simulate pedide screw insertion in the lumbar spine. A total of 12 orthopedic senior house officers performed pedide screw insertion in the lumbar spine before and after the training on training system. The results were assessed based on the scoring system, which included the amount of time taken, accuracy of pedide screw insertion, and the number of exposures requested to complete the procedure.RESULTS: The result shows a significant improvement in amount of time taken, accuracy of fixation, and the number of exposures after the training on simulator system. This was statistically significant using paired Student t test (p < 0.05).CONCLUSION: Fully simulated computer-navigated training system is an efficient training tool for young orthopedic trainees. This system can be used to augment training in the operating room, and trainees acquire their skills in the comfort of their study room or in the training room in the hospital. The system has the potential to be used in various other orthopedic procedures for learning of technical skills in a manner aimed at ensuring a smooth escalation in task complexity leading to the better performance of procedures in the operating theater. (C) 2014 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
The paper presents an interdisciplinary project which is the first step towards a 3D Geographical Information System (GIS) dedicated to Cultural Heritage with a specific focus application on the Castle of Shawbak, also known as the ”Crac de Montral” in Jordan. The project continues to grow thanks to a synergy between a set of laboratories: The LSIS laboratory, France in charge of the pho- togrammetric survey phase connected with the knowledge based approach; ITABC, CNR lab in Roma, Italy in charge of the topometric survey, with DGPS and aerial photography with gas balloon, National Institute of Information and Communications Technology, Kyoto, Japan for the 3D view point seek connected to the database, the image processing aspect managed by Stratos documentation, SimVis from The Department of Computer Science, University of Hull, UK, for the virtual reality aspect and of course the Dipartimento di Studi storici e Geografici from the University of Florence, Italy, in charge of the archaeological part. Our project focuses on a building scale encompassing its atomic elements such as ashlars blocks, cement, stratigraphic units and archi- tectonic elements. At this scale we need a full 3D interface in order to manage accurate measurements, a huge quantity of observations and a mainly heterogeneous archaeological documentation. This project described in this paper is work in progress. After four photogrammetric campaigns in Jordan the first results are available on the project web site: http://www.shawbak.net
The paper presents an interdisciplinary project which is the first step towards a 3D Geographical Information System (GI S) dedicated to Cultural Heritage with a specific focus application on the Castle of Shawbak, also known as the "Crac de Montral" in Jordan. The project continues to grow thanks to a synergy between a set of laboratories: The LSIS laboratory, France in charge of the pho- togrammetric survey phase connected with the knowledge based approach; ITABC, CNR lab in Roma, Italy in charge of the topometric survey, with DGPS and aerial photography with gas balloon, National Institute of Information and Communications Technology, Kyoto, Japan for the 3D view point seek connected to the database, the image processing aspect managed by Stratos documentation, SimVis from The Department of Computer Science, University of Hull, UK, for the virtual reality aspect and of course the Diparti mento di Studi storici e Geografici from the University of Florence, I taly, in charge of the archaeological part. Our project focuses on a building scale encompassing its atomic elements such as ashlars blocks, cement, stratigraphic units and archi- tectonic elements. At this scale we need a full 3D interface in order to manage accurate measurements, a huge quantity of observations and a mainly heterogeneous archaeological documentation. This project described in this paper is work in progress. Aft er four photogrammetric campaigns in Jordan the first result s are available on the project web site: http://www.shawbak.net
The Phantom based Computer assisted orthopaedic surgical system (CAOSS) has been developed collaboratively by the University of Hull and the Hull Royal Infirmary, to assist in operations like dynamic hip screw fixation. Here we present summary of our system. CAOSS comprises a personal computer based computer system, a frame grabber with video feed from a C-arm image intensifier, an optical tracking system and a radiolucent registration phantom which consists of an H arrangement of 21 metal balls. The phantom is held in position by the optically tracked end-effector. Knowing the optical position of the phantom, a registration algorithm calculates the position of C-arm in coordinate space of the optical tracking system. Computer based planning uses an anteroposterior (AP) and lateral image of the fracture. Marks are placed on the 2D projections of femoral shaft, neck and head on the computer screen, which are then used to create 3D surgical plan. The computer then plans a trajectory for the guide wire of DHS. The depth of the drill hole is also calculated. The trajectory is then shown on both AP and lateral images on the screen. CAOSS meets all the requisite of electrical and electromagnetic radiation standards for medical equipment. There has been extensive validation using software simulation, performance evaluation of system components, extensive laboratory trials on plastic bones. The positional accuracy was shown to be within 0.7mm and angular accuracy to be within 0.2°. The system was also validated using Coordinate Measurement Machine. Our system has the unique feature of the registration phantom which provides accurate registration of the fluoroscopic image.
The use of the C-arm fluoroscope for surgical navigation in various Computer Assisted Orthopaedic Surgery Systems (CAOS) has been an important success of research into CAOS technology. To use the fluoroscope for quantitative surgical navigation involves calibrating its 2D images and tracking the spatial position of the fluoroscope's image beam. This allows 3D reconstruction of anatomy from a series of 2D fluoroscopic images. This paper presents a new technique for determining the C-arm position and calibrating the image beam. This technique is based on a small imaging phantom that is placed close to the patient. This paper also briefly describes the CAOS system developed at Hull that uses this imaging phantom and reports on in vivo and in vitro studies.
The difficult part of the intramedullary (IM) nailing operation of long bone is to insert the distal locking screws. The current technique to insert these screws uses numerous fluoroscopic images and depends on skills and expertise of the surgeon. A Computer-Assisted Orthopaedic Surgical System (CAOSS) has been developed collaboratively by the University of Hull and the East Yorkshire Hospitals NHS Trust to assist the orthopaedic surgeons in these operations. The laboratory based test results for insertion of distal locking screws in intramedullary nailing procedure are presented and discussed in terms of accuracy and as part of the validation process to introduce new CAOS procedures into clinical use. This study shows that CAOSS in IM nails is robust and reliable. The positional accuracy in planning the trajectory for insertion of the distal locking screws was shown to be within 0.3 mm and angular accuracy within 0.2°.
The standard method for gathering and representing archaeological information consists of two-dimensional layer managers. This paper presents an archaeological Geographical Information System (GIS) based on an immersive virtual environment. Our goal is to provide an immersive visualisation of multiple datasets relating to the Foulness Valley in East Yorkshire. By maximising the user's visual bandwidth within an immersive virtual environment, we have provided archeologists with greater insight into the Foulness Valley datasets using both existing and novel visualisation tools and techniques.
Implicit planar curve and surface fitting to a set of scattered points plays an important role in solving a wide variety of problems occurring in computer graphics modelling, computer graphics animation, and computer assisted surgery. The fitted implicit surfaces can be either algebraic or non‐algebraic. The main problem with most algebraic surface fitting algorithms is that the surface fitted to a given data set is often unbounded, multiple sheeted, and disconnected when a high degree polynomial is used, whereas a low degree polynomial is too simple to represent general shapes. Recently, there has been increasing interest in non‐algebraic implicit surface fitting. In these techniques, one popular way of representing an implicit surface has been the use of radial basis functions. This type of implicit surface can represent various shapes to a high level of accuracy. In this paper, we present an implicit surface fitting algorithm using radial basis functions with an ellipsoid constraint. This method does not need to build interior and exterior layers for the given data set or to use information on surface normal but still can fit the data accurately. Furthermore, the fitted shape can still capture the main features of the object when the data sets are extremely sparse. The algorithm involves solving a simple general eigen‐system and a computation of the inverse or psedo‐inverse of a matrix, which is straightforward to implement.
Aims: Dynamic hip screw (DHS) is a common implant used for extracapsular fracture neck of femur. Accurate placement of the guide wires for the DHS insertion is the most important surgical step. In order to improve precision and accuracy of the guide wire placement, Computer Assisted Orthopaedic Surgery System (CAOSS) was used , which was developed at the University of Hull. Methods: CAOSS helps in surgical planning and aid surgeons for accurate guide wire placement into femoral neck. After fracture reduction, intra-operative computer based surgical planning was performed using one fluoroscopic image in two planes each. A trajectory obtained thus helped surgeon to place a guide wire along with the required course under the computer guidance. Results: CAOSS system was used on 11 patients for guide wire placement. Intra-operative fluoroscopic images of all the patients showed accurate position of the guide wire both in AP and lateral planes. In theory only 4 fluoroscopic images are required during this surgical procedure in total. But in practice, more than 4 were required depending upon the experience of the radiographer. None of the patient had any intra-operative complication. Conclusions: The computer aided surgery was found to be safe, accurate and reliable for guide wire placement for dynamic hip screw insertion.
Aims: Dynamic hip screw for intertrochanteric fractures is one of the most common procedures performed by orthopaedic surgeons. The prerequisite for proper placement of the implant is accurate insertion of the guide wire. The Computer Assisted Orthopaedic Surgical System [CAOSS] is designed to assist the surgeon by planning the trajectory based on one intra-operative AP and Lateral image from a C-Arm. Methodology: After closed reduction on the fracture table, two near orthogonal x-ray images containing the proximal femur with the registration phantom are obtained using a standard C-Arm and then processed after distortion correction. The phantom is supported by an end effector, which is continuously tracked in 3D space. Features of interest are extracted and the image registered in space through the evaluation of the phantom’s projection in the x-ray image. The versatility of the CAOSS is increased by the provision allowing the adjustment of the planned trajectory to the surgeon’s satisfaction. Once the trajectory is accepted, the surgeon implements the plan by moving a passive manipulator arm, while receiving visual positional cues from the computer in the form of a targeting screen. When the targeting is complete; the arm is locked in position and the trajectory implemented. Results: We present the results of the pilot clinical study involving 10 patients using this device. The results obtained were compared with an equal number of patients randomly selected from the complete neck of femur database, who had undergone a conventional DHS placement, during the last one-year. Accuracy of placement of the implant was assessed by an independent observer and by a previously validated computer program that assesses the accuracy from scanned post operative X-rays. The average targeting time was 6 minutes and overall there was no significant difference between the two groups.
Hull Medical Engineering (HULMEC) group was established in 1992 as a collaboration of orthopaedic surgeons and various research groups from the University of Hull to promote multidisciplinary research especially the application of computers to aid in surgery. With the joint effort of researchers and surgeons CAOSS was developed. The key aim of the CAOSS has been to use intra-operative surgical planning using fluoroscopic based images, hence this system aids in performing those procedure which requires fluoroscopy namely dynamic hip screw guide wire insertion, distal locking of the screw and placement of cannulated hip screw. The major steps of CAOSS are the precision calibration of the fluoroscopic images, use of these images for accurate intra operative surgical planning, innovative planning algorithms, and a safe, rapid and accurate approach to trajectory execution. CAOSS has been used on the plastic bones in the laboratory setting and was found to be accurate. Presently CAOSS has been used in an ethically approved clinical trial for guide wire insertion for the DHS placement. Perceived Advantages of CAOSS Safe Passive system Non-invasive Surgeon maintains decision making Decreasing radiation exposure Reducing complexity of the procedure Reducing technical failures Reducing operating time Improving accuracy of implant placement Reducing bone damage (by reducing repeated guide wire insertion) Improving Patient outcome Cost Effective Easy to use
Web-cam based gesture recognition systems for home use are becoming more viable. A modification to an algorithm developed by Bimber yields low failure rates for wand motions tested against three sets of gestures. Additionally, the speed at which a gesture is performed does not affect its recognition rate, though the gesture's orientation does.
In intramedullary nail (IMN) surgical operations, one of the main efforts for surgeons is to find the axes of two distal holes. Two distal holes on an IMN, which are inside the intramedullary canal of a patient's femur, can only be seen in a lateral X-ray view. For the standard surgical procedure, the localization of the distal hole axes is a trial-and-error process which results in a long surgical time and large dose of X-ray exposure. In this paper, an algorithm to derive the three-dimensional position and orientation of the distal hole axis was developed. The algorithm first derives the nail axis through two X-ray images. Then the distal hole axis is calculated through projecting back the hole boundary on the X-ray image from a lateral view to three-dimensional space. A least-squares method is used to determine the centres of the front hole and the back hole through iteration. The algorithm has been tested with real data and it was robust.
The C-arm fluoroscope is an indispensable intraoperative 2D imaging device for orthopaedic surgery. However, its frequent use in an operation presents a significant radiation hazard to the. theatre staff and patient. A recent technique known as virtual fluoroscopy (VF) enhances the fluoroscope's capability for image guided surgery by tracking optically the position of the C-arm, surgical instruments and the patient. Virtuality is achieved by overlay of surgical instruments onto one or more previously captured fluoroscopic images. A key benefit of VF is that it reduces considerably the radiation hazard. This paper reports on a new VF technique for tracking and calibration of the fluoroscopic C-arm. Also reported is the use of our VF system to provide a new image guided technique for the accurate placement of the femoral component of unicompartmental knee prosthesis.
This project extends previous work on stereographic projection of 2D x-ray images and aims to overcome a number of problems, namely: confusing stereo cues; distortion between stereo pairs; and increased radiation exposure from additional x-ray images. Images are distortion corrected and a polygonal representation of a bone fitted to the x-ray image, to approximate the bone surface. The polygonal representation is rendered and blended with the x-ray image to add surface detail, without obscuring salient features within the original x-ray. A reduction in x-ray exposure by using a stereo pair of computer-generated polygonal bone images blended with a mono x-ray image is investigated. An experiment provides evidence that depth perception is increased with the inclusion of bone surface rendering, and is achievable with a mono x-ray image.