bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical Simulation of the Interosseous Ligaments During Forearm Rotation
Authors: Péan Fabien , Carrillo Fabio , Fürnstahl Philipp , Goksel Orcun 
Published: February 2018

The Interosseous Membrane (IOM) is a fibrous ligament bundle connecting the ulna and the radius. It is well known that the IOM allows transferring partial load from the radius to the ulna (Pfaeffle 2005). It also influences the kinematics of the radioulnar joint (Yasutomi 2002, Tarr 1984).Three-Dimensional (3D) computer-assisted methods for preoperative planning of osteotomy have been applied successfully on forearm pathologies (Fürnstahl 2010, Murase 2008, Vlachopoulos 2015). However, to the best of our knowledge, models and studies of the influence of the IOM during pro-supination are limited to a kinematics analysis of the system, either with actual bone geometry (Fürnstahl 2009) or without it (Kasten 2002). In this work, we present a physical simulation of the forearm pro-supination involving the IOM biomechanical properties, for providing insights on the influence of the IOM on the radioulnar motion. We demonstrate a preliminary validation using a sample simulation performed on a healthy forearm by comparing its outcome with literature, and analyze the kinetic data that our method allows.
ARSuikawARi
Authors: Ichimura Yuuki , Nagano Fumiya , Idehara Norimichi 
Published: February 2018

This system enables the user to experience Suika-wari play in augmented reality world. Suika-wari is a Japanese popular play commonly played by the seaside in summer. The main player tries to hit a watermelon (suika) with a stick while being blindfolded and surrounding players indicates the position of the watermelon only with the voice.In this system, the visitors play either roles of the two players. The players share the same augmented reality world where a watermelon is placed. Original play usually uses only one watermelon, but we offer the joy to hit as many watermelons as possible during a certain period.
Heat resistant electronic modules for intelligent medical sterile containers
Authors: Böhler Lukas , Daniol Mateusz , Kleinhans Lukas , Keller Anton , Sroka Ryszard 
Published: February 2018

The digitalisation gets more and more important in our daily life. Also in medical technology instruments and devices need to become intelligent and be able to both collect and provide additional data. This research is about the development of an electronic sensor system for sterilisable medical containers. Hereby just a few concepts exist to equip the containers with sensor modules but the high temperature of 135 °C during the sterilisation is still a big challenge.The objective for this research is to find a heat resistant insulation for an electronic system with a power supply, sensors for both sterilisation and transport and a low power communication module. Furthermore, the thermal energy of the sterilisation shall be used for powering up the system.In a first step an epoxy resin was used to insulate the electronics and a high temperature battery. By using the temperature sensor of a Bluetooth module the module temperature could be measured during multiple steam sterilisations. Following, a partly insulated thermoelectric generator shall be used to get energy by the achieved temperature difference.First results show that the used epoxy resin limits the temperature to 81 °C. However, the resin was damaged after 21 sterilisation cycles due to its high mass and entrapped air. Therefore, the insulation needs to be minimized and the electronic components need to be able withstanding higher temperatures. Additionally, insulations with not yet considered materials will be tested. Also the possibility of insulating just heat-sensitive parts like the power elements will be investigated.
Ten year survival of navigation-assisted total knee arthroplasty.
Authors: Jenny Jean-Yves 
Published: February 2018

Total knee arthroplasty (TKA) is considered a highly successful procedure. Survival rates of more than 90% after 10 years are generally reported. However, complications and revisions may still occur for many reasons, and some of them may be related to the operative technique. Computer assistance has been suggested to improve the accuracy of implantation of a TKA (Jenny 2005). Short term results are still controversial (Roberts 2015). However, few long term results have been documented (Song 2016). The present study was designed to evaluate the long-term (more than 10 years) results of a TKA which was routinely implanted with help of a non-image based navigation system. The 5- to 8- year of this specific TKA has already been documented (Jenny 2013).The hypothesis of this study will be that the 10 year survival rate of this TKA will be improved in comparison to historical papers when analyzing survival rates and knee function as evaluated by the Knee Society Score (KSS).
Robotic-Arm Assisted Total Knee Arthroplasty Demonstrated Soft Tissue Protection
Authors: Hampp Emily , Bhowmik-Stoker Manoshi , Scholl Laura , Otto Jason , Jacofsky David , Mont Michael 
Published: February 2018

Total knee arthroplasty (TKA) typically addresses end-stage osteoarthritis. While TKA procedures have demonstrated clinical success, occasionally intraoperative complications can occur. This cadaver study examined the potential benefits of soft tissue protection in robotic-arm assisted TKA (RATKA). Six cadaver knees were prepared using RATKA by a single surgeon from a high-volume TKA joint center with no former clinical robotic experience, and compared to seven manually performed cases as a control. The presence of soft tissue disruption was assessed by having the surgeon perform visual evaluation and palpation of the medial collateral ligament (MCL), lateral collateral ligament (LCL), posterior cruciate ligament (PCL), and the patellar ligament after the procedures. The amount of tibial subluxation and patellar eversion was recorded for each case.For all RATKA cases, there was no visible evidence of disruption of any of the ligaments. All RATKA cases were successfully left with a bone island on the tibial plateau, which protected the PCL. Tibial subluxation and patellar eversion were not required for visualization. In two of the seven MTKA cases, there was slight disruption noted of the PCL, although this did not lead to any apparent change in the functional integrity of the ligament. All MTKA cases required tibial subluxation and patellar eversion to achieve optimal visualization.Aspects of soft tissue protection were noted in this cadaver study for RATKA. Standard retraction techniques during cutting are recommended. This is the first study to have soft tissue injury parameters assessed for RATKA, and may serve as a platform for future studies.
Sensor Integrated Instruments for Surgical Quality Assurance and Process Monitoring
Authors: Strathen Benjamin , Janß Armin , Gödde Peter , Radermacher Klaus 
Published: February 2018

Demographic changes will increase the number of surgical procedures in the next years. Therefore, quality assurance of clinical processes, such as the reprocessing of surgical instruments as well as intraoperative workflows will be of increasing importance to ensure patient safety. Surgical procedures are often complex and may involve risks for the patient. For fixation of screws, e.g. in case of pedicle screws, osteosynthesis plates or revision joint replacement surgery implants, the application of defined torques may be crucial in order to achieve optimal therapeutic results and minimal complication rates. In many cases a subjective rating of the surgeon is necessary as no adequate instrumentation is available. With the same subjective feeling, hammering or screwing in are performed to implant e.g. the acetabular component in THA.Our actual work is dedicated to the implementation of a functional prototypes of sensor-integrated instruments for specific types of intervention (especially in traumatology) and the evaluation of the sensor integrated surgical instruments in combination with RFID technology for smart process optimization in the operating room as well as for reprocessing of surgical instruments and surgical management in combination with a knowledge-based planning, control and documentation system. Complementary (preferably wireless) sensors such for instrument identification, tracking or more complex measurements such as forces, torques, temperature or impacts during surgery as well as during reprocessing of reusable instruments could enable computer network based quality assurance in a much broader and comprehensive manner.Within the framework of the OR.NET initiative we follow the approach to integrate wireless sensors for measurement of temperature, force-torque as well as inertial sensors for orientation and impact control, depending on the specific type of application for monitoring of workflows during surgery as well as during reprocessing of reusable instruments and devices. The integration of smart surgical instruments into an open networked operating room based on the open communication standard IEEE 11073 knowledge-based workflow system, can help to improve the process and quality management.
Clinical and Radiological Results from Reconstruction of Massive Acetabuar Defects Using 3D Printed Trabecular Titanium Implants
Authors: Henckel Johann , Durand-Hill Matthieu , Noory Sabir , Skinner John , Hart Alister 
Published: February 2018

Additive manufacturing has enabled a radical change in how surgeons reconstruct massive acetabular defects in revision hip surgery. We report on the early clinical and radiological results from our methods for surgical planning, design, and implantation of 3D printed trabecular titanium implants in a cohort of patients with large unclassifiable pelvic defects.We set up a prospective investigation involving 7 consecutive patients. Inclusion criteria was the following: 1) A history of previous total hip replacement; and 2) Current imaging showing at least a Paprosky 3B defect. Planned acetabular inclination and version was 40° and 20° respectively. Post operatively all patients had a CT scan which was analysed with software to determine component position and compared to planned. Outpatient review was done at 2 weeks (For wound), 6 weeks (for weight bearing and fixation) and 52 weeks (for fixation and infection) post-operative.3 Themedianageatsurgerywas:65years(40-78).Themedianbonedefectvolumewas140cm .Mediansurgery length was 5.2 hours (3-6.25). Median blood loss was 1300mL (450- 2000). Radiologically, components were stable and no screw breakages were identified. Achieved inclination was 41.0° (29.0- 55.6) and achieved version was 15.8° (3.8-43.6). Median Oxford Hip score improved from 9 (2-44) to 25 (18-32).We have demonstrated a new series of pre, intra and post-operative methods for reconstruction of unclassifiable acetabular bony defects. Initial clinical and radiological results are excellent considering the severity of the bony defects. We recommend the use of our or similar methods when trying to reconstruct these defects.
Augmented Marker Tracking for Peri-acetabular Osteotomy Surgery: A Cadaver Study
Authors: Pflugi Silvio , Lerch Till , Vasireddy Rakesh , Boemke Nane , Tannast Moritz , Ecker Timo Michael , Siebenrock Klaus , Zheng Guoyan 
Published: February 2018

Purpose. To validate a small, easy to use and cost-effective augmented marker-based hybrid navigation system for peri-acetabular osteotomy surgery.Methods. A cadaver study including 3 pelvises (6 hip joints) undergoing navigated PAO was performed. Inclination and anteversion of two navigation systems for PAO were compared during acetabular reorientation. The hybrid system consists of a tracking unit which is placed on the patient’s pelvis and an augmented marker which is attached to the patient’s acetabular fragment. The tracking unit sends a video stream of the augmented marker to the host computer. Simultaneously, the augmented marker sends orientation output from an integrated inertial measurement unit (IMU) to the host computer. The host computer then computes the pose of the augmented marker and uses it (if visible) to compute acetabular orientation. If the marker is not visible, the output from the IMU is used to update the orientation. The second system served as ground truth and is a previously developed and validated optical tracking-based navigation system.Results. Mean absolute difference for inclination and anteversion (N = 360) was 1.34 degrees and 1.21 degrees, respectively. The measurements from our system show a very strong correlation to the ground-truth optical tracking-based navigation system for both inclination and anteversion (0.9809 / 0.9711).Conclusion. In this work we successfully demonstrated the feasibility of our system to measure inclination and anteversion during acetabular reorientation.
Evaluation of 2D Biomechanical Models of the Knee of One-Leg Stand for Total Knee Arthroplasty Planning
Authors: Asseln Malte , Eschweiler Jörg , Kiliclar Anika , Kutzner Ines , Bergmann Georg , Radermacher Klaus 
Published: February 2018

Biomechanical models of the knee have the potential to predict joint mechanics and improve the therapeutic outcome. In case of total knee arthroplasty (TKA) knowledge on post-operative acting joint forces and its consideration in pre-operative planning might increase implant longevity and patient satisfaction. The goal of this study was to evaluate 2D biomechanical models of the knee suitable for pre-operative TKA planning and to validate them based on in vivo measurements of 9 patients treated with instrumented knee implants.An extensive literature research on 2D biomechanical models of the knee with the requirement that patient-specific model adaption can be performed with data available in the conventional clinical workflow revealed the models of Maquet and Minns. Both models require one-leg stand AP long-leg radiographs and they output the resultant tibiofemoral joint force. For model validation, data from the freely accessible OrthoLoad database (www.orthoload.com) containing forces acting in orthopaedic implants have been used.Looking at the results, Minns’s model was in the same range as the reference forces (deviation: -55 %BW to +80 %BW) as well as Maquet’s (deviation: -80 %BW to +50 %BW). Overall, the root-mean-square error (RMSE) was smallest for Minns’ model (48.36 %BW against 51.48 %BW). The patient-specific adaptation process plus simulation took 7 to 8 minutes making the models applicable in the conventional clinical workflow with acceptable costs.In terms of clinical application, the models’ output might be consulted, e.g. to minimize the magnitude of the resultant joint force, target a specific orientation or load distribution in order to consider mechanical factors which might be associated with premature implant failure.
Morpho-Functional Analysis of Knee Implant Design for Total Knee Arthroplasty on the Example of the Trochlear Groove Orientation
Authors: Asseln Malte , Verjans Mark , Zanke Darius , Radermacher Klaus 
Published: February 2018

Total knee arthroplasty (TKA) is widely accepted as a successful surgical intervention to treat osteoarthritis and other degenerative diseases of the knee. However, present statistics on limited survivorship and patient-satisfaction emphasize the need for an optimal endoprosthetic care. Although, the implant design is directly associated with the clinical outcome comprehensive knowledge on the complex relationship between implant design (morphology) and function is still lacking.The goal of this study was to experimentally analyze the relationship between the trochlear groove design of the femoral component (iTotal CR, ConforMIS, Inc., Bedford, MA, USA) and kinematics in an in vitro test setup based on rapid prototyping of polymer-based replica knee implants.The orientation of the trochlear groove was modified in five different variations in a self-developed computational framework. On the basis of the reference design, one was medially tilted (-2°) and four were laterally tilted (+2°, +4°, +6°, +8°). For manufacturing, we used rapid prototyping to produce synthetic replicates made of Acrylnitril-Butadien-Styrol (ABS) and subsequent post-processing with acetone vapor. The morpho-functional analysis of the replicates was performed in our experimental knee simulator. Tibiofemoral and patellofemoral kinematics were recorded with an optical tracking system during a semi-active flexion/extension (~10° to 90°) motion.Looking at the results, the patellofemoral kinematics, especially the medial/lateral translation and internal/external rotation were mainly affected. During low flexion, the patella had a more laterally position relative to the femur with increasing lateral trochlear orientation. The internal/external rotation initially differentiated and converged with flexion. Regarding the tibiofemoral kinematics, only the tibial internal/external rotation showed notable differences between the modified replica implants.We presented a workflow for an experimental morpho-functional analysis of the knee and demonstrated its feasibility on the example of the trochlear groove orientation which might be used in the future for comprehensive implant design parameter optimization, especially in terms of image based computer assisted patient-specific implants.
The interleaved partial active shape model search (IPASM) algorithm – Preliminary results of a novel approach towards 3D ultrasound-based bone surface reconstruction
Authors: Hänisch Christoph , Hohlmann Benjamin , Radermacher Klaus 
Published: February 2018

In applications such as biomechanical simulations or implant planning, bone surfaces of the knee are most often reconstructed from computed tomography or magnetic resonance imaging data. Here, ultrasound (US) might serve as an alternative imaging modality. However, established methods cannot directly be transferred to US due to differences in imaging quality and underlying physics.In this paper, we present a generalisation of the well-known active shape model search algorithm (ASM) that allows for segmenting various structures in US volume images that are too large to be captured with a single recording. The multi-view segmentation approach uses a-priori knowledge in the form of a statistical shape model (SSM) as is the case with the classical ASM. This allows to extrapolate missing information and to generate shapes that comply with the underlying distribution of some training data. The main differences are, however, that the SSM is not only adapted to a single image but to multiple images and that the adaption process is interleaved. As a result, within each iteration the surface information of all sub-volumes is propagated and used in all subsequent steps.In-silico tests were conducted to investigate how this algorithm would perform in real tracked US data. US volume images were split in slightly overlapping sub-volumes, noise was added, and the alignment was distorted. We could show that the algorithm is capable of reconstructing shapes in the lower millimetre range and for some cases even with submillimetric accuracy. The algorithm is hardly affected by orientation errors below 5 degrees and displacement errors below 5 mm; above these limits, the average absolute SDE as well as its associated variance increases.
Patient specific instrumentation influences hemoglobin decrease after total knee replacement.
Authors: Cucchi Davide , Zanini Beatrice , Ferrua Paolo , Compagnoni Riccardo , Menon Alessandra , Randelli Pietro 
Published: February 2018

Patient Specific Instrumentation (PSI) may contribute to reduce blood loss after total knee replacement (TKR) by avoiding violation of the medullary canal. The purpose of the study was to compare the hemoglobin (Hb) decrease in two groups of patients undergoing TKR with PSI and conventional instrumentation.Pre- and post-operative blood samples were collected for twenty-two patients randomly assigned to receive a PSI-assisted or conventional TKR. Post- to preoperative Hb difference was calculated.A significant difference in Hb reduction in favor of the PSI group was registered on the last day of stay but not on the previous post-operative days: these promising results suggest a beneficial effect of PSI in blood loss reduction. PSI may hence be considered among the strategies available to control and reduce blood loss related to TKR.
The surgeon plays an important role in size planning with patient specific instrumentation for total knee replacement.
Authors: Cucchi Davide , Compagnoni Riccardo , Ferrua Paolo , Menon Alessandra , Randelli Pietro 
Published: February 2018

Component position and sizing in total knee replacement (TKR) could be improved by patient specific instrumentation (PSI). The purpose of the study was to evaluate the reliability of the manufacturer plan in predicting final component sizes for TKR.Forty-five TKRs were prospectively enrolled and data on component size were recorded from the initial manufacturer’s proposal, the final plan modified after surgeon’s and from the actually implanted prostheses.Pre-operative modifications were required in more than 50% of the cases, with the tibial tray size requiring more frequent changes. The surgeon’s planning showed a significantly higher accuracy than the manufacturer’s one regarding tibial tray size (p &lt; 0.05) but not femoral components size (p: n.s.). Careful evaluation by an experienced knee surgeon is recommended when planning TKR with PSI.
Comparison of Outcome and Gait Analysis after Robotic Total Knee Arthroplasty Between Mechanical and Kinematic Knee Alignment methods with and Average 8 Years Follow Up
Authors: Seon Jong-Keun , Song Eun-Kyoo , Lee Dong-Hyun , Yeo Je-Hyoung 
Published: February 2018

Background: There are limited previous findings detailed biomechanical properties following implantation with mechanical and kinematic alignment method in robotic total knee arthroplasty (TKA) during walking. The purpose of this study was to compare clinical and radiological outcomes between two groups and gait analysis of kinematic, and kinetic parameters during walking to identify difference between two alignment method in robotic total knee arthroplasty.Methods: Sixty patients were randomly assigned to undergo robotic-assisted TKA using either the mechanical (30 patients) or the kinematic (30 patients) alignment method. Clinical outcomes including varus and valgus laxities, ROM, HSS, KSS and WOMAC scores and radiological outcomes were evaluated. And ten age and gender matched patients of each group underwent gait analysis (Optic gait analysis system composed with 12 camera system and four force plate integrated) at minimum 5 years post-surgery. We evaluated parameters including knee varus moment and knee varus force, and find out the difference between two groups.Results: The mean follow up duration of both group was 8.1 years (mechanical method) and 8.0 years (kinematic method). Clinical outcome between two groups showed no significant difference in ROM, HSS, WOMAC, KSS pain score at last follow up. Varus and valgus laxity assessments showed no significant inter-group difference. We could not find any significant difference in mechanical alignment of the lower limb and perioperative complicatoin. In gait analysis, no significant spatiotemporal, kinematic or kinetic parameter differences including knee varus moment (mechanical=0.33, kinematic=0.16 P&gt;0.5) and knee varus force (mechanical=0.34, kinematic=0.37 P&gt;0.5) were observed between mechanical and kinematic groups.Conclusions: The results of this study show that mechanical and kinematic alignment method provide comparable clinical and radiological outcomes after robotic total knee arthroplasty in average 8 years follow-up. And no functional difference were found between two knee alignment methods durning walking.