bluuebunny/crossref_metadata_2025 huggingface dataset:
Interculturalidade, Jurisdição Indígena e a Constituição Federal de 1988
Authors: Moreira Erika Macedo , Resende Ana Catarina Zema de , Resende Ana Catarina Zema de , Resende Ana Catarina Zema de
Published: October 2019

Desde o início da colonização, os povos indígenas têm resistido às sucessivas tentativas de desestruturação social e de sua capacidade de autogoverno, inclusive em matéria de justiça. Apesar da violência colonial, de séculos de políticas assimilacionistas e dos postulados monistas da sociedade dominante, eles lograram conservar seus sistemas jurídicos próprios. No entanto, em um contexto em que o Estado continua mantendo e reproduzindo a colonialidade do poder como lógica dominante da razão jurídica, a coexistência das culturas jurídicas indígenas com a estatal permanece problemática. Esse artigo pretende examinar em que medida o quadro constitucional brasileiro determina a recepção da jurisdição indígena.
Accuracy of Ratio for Centre of the Ankle Method as a Landmark for Proximal Tibial Cutting in Computer Assisted Total Knee Arthroplasty Compared with Extramedullary Method
Authors: Vejjaijiva Anuchit , Sriphirom Pornpavit , Saepoo Chalit , Ounjitti Weeravut , Suwansawaiphol Soros
Published: October 2019

Proximal tibial resection is an important surgical step in total knee arthroplasty (TKA). Normally, an anterior surface of tibia used as anatomical landmark (extramedullary method), this method based on visual judgment. (D.C. Marchant, 2005) calculated ratio for center of the ankle, ratio of lateral distance to total inter-malleolar distance was observed at 0.57 in normal ankle sample. However, there is no study documenting about accuracy of ratio for center of the ankle as a landmark for proximal tibial resection in computer assisted TKA (CAS TKA).

This was prospective study on 65 patients with osteoarthritis knees scheduled to receive CAS TKA from January to December 2018. Proximal tibial resection was simulated by extramedullary method and ratio for center of the ankle respectively. Tibial resection alignment were recorded by CAS.

Tibial resection alignment within 3 degrees was 84.6 and 92.3% for extramedullary method and ratio for center of the ankle method. The average total tibial resection alignment was 0.84 and 0.66 degrees of valgus (p = 0.497), the average tibial resection alignment within 3 degrees from mechanical axis was 0.33 and 0.55 degrees of valgus (p = 0.513) and the average tibial resection alignment more than 3 degrees from mechanical axis was 3.60 and 1.5 degrees of valgus (p = 0.049) for extramedullary method and ratio for center of the ankle method respectively.

Ratio for center of the ankle demonstrated result in numeric value and anatomical landmark of lateral and medial malleoli was simple to identified. Our results shown the tibial resection alignment with ratio for center of the ankle method had higher accuracy and lower average degrees of outlier than extramedullary method.
Comparison of Clinical Outcomes After Total Hip Arthroplasty with and without Computed Tompgraphy-Based Navigation System for Osteonecrosis of the Femoral Head: a Propensity Score Matched Analysis
Authors: Takashima Kazuma , Sakai Takashi , Hamada Hidetoshi , Ando Wataru , Takao Masaki , Sugano Nobuhiko
Published: October 2019

This study aimed to investigate whether use of a computed tomography (CT)-based navigation system reduce the risk of dislocation after total hip arthroplasty (THA) in patients with osteonecrosis of the femoral head (ONFH). A total of 271 hips from 192 consecutive patients that underwent primary THA for ONFH were included. There were 110 hips in non-navigation group, and 161 hips in navigation group. After applying exclusion criteria, 209 hips from 149 patients were selected for this study. Clinical outcomes and complication rates were evaluated, and implant alignments were also calculated. To identify whether the navigation system was useful to prevent dislocation, the inverse probability of treatment weighted Cox regression analysis using a propensity score in relationship to sex, age at surgery, body mass index, and femoral head size was performed. No significant difference was observed in clinical scores between both groups. Dislocation was significantly lower in the navigation group (3 hips, 2.7%) than in the non-navigation group (11 hips, 11.2%; p = 0.012), whereas periprosthetic joint infection and aseptic loosening did not differ between the groups. Variance of cup angle was smaller in the navigation group than in the non-navigation group (p < 0.001). Use of the CT- based navigation system (HR; 0.26, 95% CI, 0.07–0.98; p = 0.047) turned out to be the predictor for preventing dislocation. In conclusion, use of the CT-based navigation system provided a precise placement of components, and thus help prevent dislocation in patients with ONFH in the propensity score analysis.
Femoral component rotation angle after unicompartmental knee arthroplasty using the anatomical tibial component cutting technique with computer-assisted surgery by CT-scan
Authors: Thienthong Kittikun , Sriphirom Pornpavit , Vejjaijiva Anuchit , Suwansawaiphol Soros
Published: October 2019

Complication following UKA in medial compartment OA knee often related to rotatory malposition of the femoral component The purpose of this study was to study outcome following Femoral component rotation angle after unicompartmental knee arthroplasty using the anatomical tibial component cutting technique with computer-assisted surgery by CT-scan measurement in Rajavithi hospital

Retrospective descriptive study of 16 patients performed medialUKA in Rajavithi Hospital Bangkok Thailand.Single orthopedic surgeon and using computer-assisted with anatomical tibia cutting technique(tibial resection in 3-degree varus).

The femoral component rotation was assessed in an axial cut CT scan. measure angle between Epicondylar axis and Posterior condylar axis

The authors analyzed 16 knees with mean age about 56 years, male 2 Female 14 and the mean BMI was 24 kg/m 2 (average body weight 63 kg)

Mean of Femoral component rotation angle in this study is 2.94-degree internal rotation(internal rotation compare with Epicondylar axis). A range of femoral component internal rotation was 0-6 degree .mean varus-valgus angle was 1.81-degree varus and mean flexion-extension angle was 5.56-degree flexion

Femoral component rotation angle in unicompartmental knee arthroplasty(UKA) in medial compartment osteoarthritis knee with using of the computer-assisted with anatomical tibia cutting technique have a favorable result (Mean = 2.94-degree internal rotation 1.81-degree varus and 5.56-degree flexion).
A Robotic Nondestructive Osteochondral Tissue Harvesting for Autograft Transplantation
Authors: Biswas Pradipta , Sikander Sakura , Kulkarni Pankaj , Song Sang-Eun
Published: October 2019

Osteoarthritis is the degeneration of bone-cartilage. Healthy cartilage absorbs mechanical stress and provides smooth limb movement. Cartilage has poor healing capabilities due to the absence of blood, lymphoid tissue, and nerve that makes treatment of the damaged cartilage difficult, making surgical intervention an inevitable solution. Mosaicplasty is a popular surgical practice involving transplantation of small cylindrical bone-cartilage plugs to refill the lesion. A lack of custom-shaped donor harvesting mechanism makes it impossible to fill the lesion with a single graft. The success of transplanting a customized autograft to replace the osteochondral lesion lies in effective extraction of the autograft from the donor site. Currently, no method exists to harvest such grafts since it requires access to the root side of donor. In this paper, we propose a robotic cartilage-bone removal mechanism to harvest a custom-shaped autograft. Our method involves drilling a profile determined from the lesion to be removed and slicing off the desired cartilage-bone graft from the root. We designed a new graft removal mechanism capable of inserting a thin wire saw and slicing through the root of the prepared profile to extract an intact autograft. The device can be attached to a standard 6- DOF robotic arm that can provide profile drilling and gross positioning of the graft removal device.
Validation of Patient Specific Surgical Guide for Curved Periacetabular Osteotomy
Authors: Sakai Takashi , Hamada Hidetoshi , Takao Masaki , Sugano Nobuhiko
Published: October 2019

In order to elucidate the accuracy of pelvis osteotomy patient specific surgical guide (PSG) setting comparing between the preoperative planning and intraoperative computed tomography (CT), and to determine the usefulness of PSG comparing between the preoperative planning and postoperative CT in curved periacetabular osteotomy (CPO), we performed experimental study using fresh cadaver samples. A total of 18 hips from 9 fresh cadaveric samples used. All hips were imaged from the whole pelvis to the femoral condyles using helical CT to design the preoperative planning and to produce PSG. PSG consisted of osteotomy guide part and rotation guide part of the bone fragments. CPO with PSG was performed in 9 hips (PSG group) while CPO without surgical guide was performed in other 9 hips (manual group). The absolute errors between the preoperative planning and PSG setting for CPO were acceptable. The absolute errors in PSG group between the preoperative planning and the surgery was significantly smaller in the flexion angle, the anteroposterior direction, and the osteotomy lines of the ilium than in manual group. The PSG for CPO is useful for the osteotomy of the pelvis and for the rotation of the acetabular bony fragment.
Combining Multiple Technologies to Achieve Optimized Surgical Outcomes in Total Knee Arthroplasty
Authors: Gordon Alexander
Published: October 2019

Purpose

Innovative technologies such as robotic assistance and intraoperative load sensors for total knee arthroplasty (TKA) aim to reduce outliers, as well as to address patient dissatisfaction. There is currently no information available that assesses the findings of using these technologies together during TKA.

Methods

Intraoperative data on alignment, gap spacing, and quantitative balance was prospectively collected in a cohort of 79 consecutive TKAs performed with robotic assistance. An instrumented trial component was utilized that captured medial and lateral tibio-femoral loads, allowing the quantitative assessment balance.

Results

Of the 79 knees, 58 (73%) had varus alignment and 21 (37%) had valgus. We divided these groups into correctable and fixed deformities. Correctable varus knees: At trial reduction 30% of the knees demonstrated quantitative imbalance at trial reduction. Fixed varus knees. At trial reduction 55% (of knees were deemed imbalanced. Correctable valgus knees: At trial reduction, 35% were imbalanced. Fixed valgus knees: Half of the knees (n=2) were imbalanced at trial reduction. The imbalance in all groups was addressed with combinations of bone and soft tissue adjustments so that at final implantation 99% of cases (n=78) were quantitatively balanced

Conclusion

While the robot was both precise and accurate with its cuts to create appropriate gap spaces, only 57% were quantitatively balanced. Ultimately, almost all knees were balanced with final implants, but that state required the use of additional techniques, including soft tissue and bony modifications. More data is needed to determine if these technologies will equate to increased clinical success.
Can standard implants reproduce the native kinematics of a TKA patient?
Authors: Quilez Maria Paz , Delport Hendrik Pieter , Wirix-Speetjens Roel , Wesseling Mariska , Perez Anson Maria Angeles , Jonkers Ilse , Vander Sloten Jos
Published: October 2019

Total knee arthroplasty (TKA) is a reliable surgical procedure, yet up to a fifth of primary implant patients remains unsatisfied. Musculoskeletal modeling (MSM) has the potential to explore the relationship between implant alignment and functional outcome [3]. Consequently, implant alignment can be quantitatively optimized to restore the pre- TKA joint behavior and, therefore, achieve the most favorable functional outcome for the specific patient. For this reason, we developed a method to optimize the implant alignment, with the aim of restoring the native kinematics and ligament elongations of the patient before undergoing TKA. Subject-specific optimization towards ligament elongations demonstrated to accurately emulate the pre-TKA ligament behavior, in contrast to the mechanically aligned approach. However, the values of the optimized implant positions resulting from the pre-TKA kinematic optimization were extreme in some cases. The presented modelling approach is a promising starting point for allowing surgeons to evaluate the patient-specific implant alignment and restore the patient- specific biomechanics.
How Does Robotic Technology Influence TKA Implant Placement For Surgeons In Fellowship Training?
Authors: Scholl Laura , Hampp Emily , de Souza Kevin , Chang Ta-Cheng , Westrich Geoffrey , Mont Michael
Published: October 2019

Implant malalignment during TKA may lead to suboptimal outcomes. Accuracy studies are typically performed with experienced surgeons; however, it is important to study less experienced surgeons when considering teaching hospitals where younger surgeons are operating. Therefore, the purpose of this study was to assess whether computer-assisted TKA (CATKA) allows for more accurate and precise implant position to plan when compared to manual TKA (MTKA) when the surgery is performed by less experienced surgeons.

Two surgeons, currently in their fellowship training and having minimal CATKA experience, performed a total six MTKA and six CATKA on paired cadaveric knees. Computed tomography (CT) scans were obtained for each knee pre- and post- operatively. CT scans were analyzed to compare post-operative implant position to the pre-operative planned position. Mean system errors and standard deviations were compared between CATKA and MTKA for the femoral component sagittal, coronal, and axial planes and the tibial component in the sagittal and coronal planes. A 2-Variance testing was performed using an alpha=0.05.

CATKA had greater accuracy and precision to plan than MTKA for: femoral axial plane (1.1o±1.1o vs. 1.6o±1.3o), coronal plane (0.9o±0.7o vs. 2.2±1.0o), femoral sagittal plane (1.5o±1.3o vs. 3.1o±2.1o), tibial coronal plane (0.9o±0.5o vs. 1.9o±1.3o) and tibial sagittal plane (1.7o±2.6o vs. 4.7o±4.1o). There was no statistical difference between surgical groups or between the two surgeons performing the cases.

With limited CATKA experience, the fellows showed increased accuracy and precision to plan for femoral and tibial implant positions. Furthermore, these results are comparable to what has been reported for an experienced surgeon performing CATKA.
Clinical and Functional Outcomes of Robotic Assisted Bicompartmental Knee Arthroplasty
Authors: Moore Ryan , Coon Thomas , DeBattista Jennifer , Shi Sarah , Valentino Alexandra , Bhowmik-Stoker Manoshi
Published: October 2019

This study reports on mid-term survivorship and outcomes of medial bicompartmental robotic assisted primary knee arthroplasty.

Forty-six knees in 43 patients with a mean 6 year follow up were consented to participate in this retrospective data collection. All patients received primary treatment for knee osteoarthritis with fixed metal backed medial femoral and patellar implants. Demographic data along with post-operative outcomes were collected including; the KSS patient portion, implant survivorship, and patient satisfaction.

All patients were included in the survivorship analysis. 45 knees in 42 patients were available for analysis of KSS and patient satisfaction. The mean follow-up was 6.1 years (range 2.1 - 7.6 years). Sixty-three percent of patients were male and 37% female. Average age at the time of surgery was 67 years and average BMI was 29. There were 3 revisions and 1 arthroscopic surgery resulting in 97.8% all cause survivorship. 86.7% of patients reported walking more than 10 blocks and 95.6% of patients reported walking without the use of assistive devices for support. All patients were able to go up and down stairs, 48.9% required use of a rail. 82.2% of patients reported being satisfied with their knee at 5 years.

In this study we found 97.8% survivorship at a mean 6 year follow up with 82.2% of patients being very satisfied or satisfied with the implant. Longitudinal follow up at 7 and 10 years will continue to evaluate long term outcomes on the variations of robotic assisted knee arthroplasty.
Imageless computer assisted navigation in ceramic-on-ceramic total hip arthroplasty vs. manual approach: a single-centre retrospective study
Authors: McLoughlin John , Mathew Mo , Grant Stephen
Published: October 2019

Background: Acetabular cup positioning is vital to the long-term survivorship of total hip arthroplasty (THA). Malalignment has been linked to dislocation, wear and osteolysis. Although there are many studies demonstrating the reduction in variability of cup positioning with computer-assisted techniques, there are relatively few reporting long-term patient reported outcomes and revision rates. Aim: The aim of this study was to review whether those patients who underwent navigated THA had better long-term survivorship or better patient reported outcomes. Methods: We compared revision rates and Oxford hip scores of 152 THAs (47 navigated and 105 non-navigated) performed at a single site between 2003 and 2008, with a minimum follow-up of 10 years. Results: 9 of the non-navigated and none of the navigated hips were revised at 10 year follow-up (p=0.057). There were no observable differences in 10-year Oxford hip scores between the navigated and non-navigated hips, 44.82 and 43.38 respectively. Conclusion: With respect to the rate of revision, although statistical significance was not achieved, it can be shown from our data that there was a clinically significant reduction in revision rates with navigated vs. non-navigated techniques. More data with higher patient numbers in the navigated cohort may be required to validate the results of our study.
3D Pose Estimation with Depth Camera for Markerless Cumputer Assisted Orthopaedic Surgery
Authors: Ogor Jérôme , Dardenne Guillaume , Sta Salaheddine , Bert Julien , Letissier Hoël , Stindel Eric , Hamitouche Chafiaa
Published: October 2019

Surgical navigation systems have been used in orthopaedics for many years. These solutions however often mean additional time and complexity because, essentially, of the markers. We want to introduce a new solution based on depth camera which could be used intraoperatively to estimate the 3D pose of surgical instruments without specific markers. The goal of this paper is to assess, on synthetic data, an algorithm called Clustered Viewpoint Feature Histogram (CVFH) to estimate the pose of an orthopaedic cut guide used during knee surgeries. A specific simulator has been developed for this study which allows the simulation of a point cloud associated to the cut guide. The Average Distance Distinguishable (ADD) metric has been measured 1000 times according to several cut guide orientations and several noise levels. The success rate has also been analyzed. It is commonly considered that the pose is correctly estimated if ADD is less than 10% of the largest dimension of the object. The ADD metric and the success rate vary from 2.12 ± 4.46 mm to 2.82 ± 5.73mm and from 96.0% to 92.4% for respectively a low (0 mm) and a high noise (10mm). The results are very promising. However, more parameters have to be assessed. Similarly, the accuracy and reliability of such method have to be evaluated in a real clinical environment.
Early Experience with CAOS Enhanced Total Knee Arthroplasty – A Global, Multi-surgeon Evaluation
Authors: Dai Yifei , Bauler Valerie , Delpech Stephan , Gradisar Ian , Lewandowski Phillip , Morrison Jefferson Craig
Published: October 2019

This study investigated surgeons’ perceptions of their experience while adopting a novel CAOS enhanced mechanical instrument system for TKA, including ease of usage, task complexity, and demands of surgical time and physical activity. A group of 9 surgeons from multiple countries with no experience in the investigated system used the CAOS enhanced mechanical instrument system during their surgical practice. After performing each TKA case, the surgeon independently completed a 6-section questionnaire formulated to survey his/her experience with the case. The results demonstrated high level of surgeons’ experiences with the adoption of the CAOS enhanced conventional instrumentation, with particularly satisfying experiences in minimum demand of time in landmark acquisition and disruption of the existing surgical process.
CT-Based Navigation THA Using CT-Fluoro Matching Registration
Authors: Tokunaga Kunihiko
Published: October 2019

CT-fluoro matching (CFM) registration is one of the registrations for CT-based navigation developed by Brainlab company, in which the contours of the intraoperative fluoroscopic 2D X-ray images were matched to the contours of 3D pelvic and femoral models created based on the preoperative CT images. Brainlab company stopped to provide CT-based navigation and shifted to imageless navigation for THA. Therefore, clinical efficacy of this CFM registration is not well known. We analyzed the accuracy of implant position and postoperative complications after CT-based navigation assisted THA of 45 cases (43 females, 2 males, average age: 72.7 y.o.) using CFM registration and cementless implants (SQRUM cups and J-Taper high offset stems [Kyocera, Japan]). The differences (average ± standard deviation of absolute values, [95% confidence interval]) between the pre- and post- operative angles of cup inclination, anteversion, and stem antetorsion were 2.2 ± 1.50, [1.8~2.60], 3.7 ± 3.10, [2.9~4.60], 5.9 ± 4.50, [4.6~7.10], respectively. The differences (average ± standard deviation of absolute values, [95% confidence interval]) between the intra- and post-operative angles of cup inclination, anteversion, and stem antetorsion were 2.2 ± 1.70, [1.7~2.60], 2.3 ± 2.10, [1.7~2.80],4.6 ± 3.00, [3.7~5.40], respectively. These values were clinically acceptable when we compared with the previous accuracy studies of CT-based navigation using surface matching registration. There was no dislocation after THA in this study. From these results, CFM registration is useful for THA. However, this CT-based navigation with CFM registration will be discontinued in near future. Novel CT-based navigation systems should be developed based on this CFM registration procedure.
Usability and Accuracy assessment of an innovative low dose C-arm with 2D fluoroscopy, 3D imaging and real-time navigation in a single platform for spine surgery – a cadaveric experimentation
Authors: Sledge John , Lavallee Stephane , Genna Sophie , Chabanas Laurence
Published: October 2019

Introduction

Clinical benefits of intra-operative 3D imaging and surgical navigation are widely described in the literature. However, existing guidance systems are often reported as complex and time consuming1,2,4. The Surgivisio / eCential system is an innovative intra-operative C-arm combining 2D fluoroscopy, 3D imaging and real time navigation capabilities within unified an all-in-one platform3.

The aim of this cadaveric experimentation is to evaluate the usability of the system, and to assess pedicle screw placement using this novel device.

Material and methods

Surgivisio / eCential device offers an all-in-one solution with a unique workflow and user interface. The embodiment used here is dedicated to any spinal procedures requiring insertion of a trocar inside a pedicle.

The usability of the system is assessed by measuring the ability of the user to navigate the trocar and place k-wires percutaneously inside a group of pedicles.

The accuracy of screw placement is evaluated using post-operative 3D image of the implanted screw exported on an internally developed image visualization tool. The screw placement is assessed according to Gertzbein grading scale by the operator and two other evaluators.

Results

Usability

For each vertebrae group, fixation of the patient reference to the end of 3D reconstruction was done in less than 10 minutes. The percutaneous navigation and placement of 6 k-wires in a vertebrae group could be performed in 28 minutes for the first 2 groups and in 22 minutes for the third group.

Pedicle screw implantation

100% of screws was graded 0 on Gertzbein scale by all evaluators.
Bony Resection Outliers: Insights from 10,144 Clinical Cases using A Contemporary Computer-Assisted Total Knee Arthroplasty System
Authors: Dai Yifei , Bolch Charlotte , Gao Siyuan , Jung Amaury , Hamad Cyril
Published: October 2019

This study accessed the alignment outliers of intraoperatively measured bony resection during total knee arthroplasty on 10,144 cases performed using a modern CAOS system. The impacts from geographic regions, surgeon’s adoption of the technology (learning or proficient phases), and historical progression of the CAOS application (software versions) were evaluated. The comprehensive analysis demonstrated that the CAOS system is a robust and accurate solution to assist the surgeons to achieve his/her surgical resection goals across its application history.
Ultrasound Guided Pedicle Screw Entry Point Identification for Spinal Fusion Surgery
Authors: Qi Xiao , Vives Michael , Hacihaliloglu Ilker
Published: October 2019

Accurate identification of the location the vertebra and corresponding pedicle is critical during pedicle screw insertion for percutaneous spinal fusion surgery. Currently, two dimensional (2D) fluoroscopy based navigation systems have extensive usage in spinal fusion surgery. Relying on 2D projection images for screw guidance results in high misplacement rates. Furthermore, fluoroscopy-based guidance exposes the surgical staff and patient to harmful ionizing radiation. Real-time non-radiation-based ultrasound (US) is a potential alternative to intra-operative fluoroscopy. However, accurate interpretation of noisy US data and manual operation of the transducer during data collection remains a challenge. In this work we investigate the potential of using multi-modal deep convolutional neural network (CNN) architectures for fully automatic identification of vertebra level and pedicle from US data. Our proposed network achieves 93.54% vertebra identification accuracy on in vivo US data collected from 27 subjects.
Assessment of Shoulder Mobility and Stability in Reverse Total Shoulder Arthroplasty: a Sensor Perspective
Authors: Verstraete Matthias , Conditt Michael , Parsons Moby , Decerce Joseph , Goodchild Gordon , Greene Alexander , Roche Chris
Published: October 2019

In reverse total shoulder arthroplasty stability is primarily controlled by the soft-tissue constraints rather than the congruency of the articulating surfaces. However, assessing the tension in these stabilizing structures currently remains highly subjective intra- operatively. In an attempt to quantify this feel during surgery, an intra-articular load sensor is introduced in this paper. In an in-vitro setting, the load sensor was used in eight reverse total shoulder arthroplasties on full torso specimens. The specimens were mounted on an inclined chair, such that the scapula could freely move to mimic surgical conditions. The resulting load vectors were captured through the range of motion under three different conditions, subjectively categorized by the surgeon as having a low, normal and high tightness. In neutral rotation and under a subjectively optimal condition assessed as neither too tight nor too loose, glenohumeral loads in the range of 10-20lbs were observed. For the same subjectively assessed optimal shoulder, loads up to 30lbs were observed under maximum internal/external humeral rotation. This contrasts the subjectively assessed loose and tight conditions, where lower resp. higher loads were observed that additionally affected the range of motion. On the other hand, stability was potentially missing under loose conditions as no increase in load was observed near the limits of the range of motion, indicating the lack of soft tissue restraint. In conclusion, this series of in- vitro experiments has shown the relevance and potential clinical value of assessing a shoulder’s stability and mobility using intra-articular load measurements during the trialing phase.
Accuracy and a learning curve of an accelerometer-based computer navigation system in total knee arthroplasty
Authors: Yo Hirotake , Ikawa Tessyu , Minami Yoshito
Published: October 2019

The aim of this study was to investigate the accuracy in performing a femoral resection and the existence of a learning curve in conducting TKA using the KneeAlign2 system. 86 primary TKAs were enrolled in this prospective study. These patients were divided in two groups.Group1: patients operated by surgeon of experience using the KneeAlign2 system more than 30 cases.Group2: patients operated by surgeons of experience using the KneeAlign2 system less than 30 cases. The radiographic results (alignment of the femoral component) and operation time were compared between the groups. There were no significant differences between the groups .The KneeAlign2 system provides usefulness in performing an accurate distal femoral resection at TKA. As the learning curve does not be observed, this portable navigation system is easy to handle even for less experienced surgeons.
Augmented-Reality within Computer Assisted Orthopaedic Surgery Workflows: A Proof of Concept Study
Authors: Iqbal Hisham , Tatti Fabio , Rodriguez Y Baena Ferdinando
Published: October 2019

The integration of augmented-reality (AR) in medical robotics has been shown to reduce cognitive burden and improve information management in the typically cluttered environment of computer-assisted surgery. A key benefit of such systems is the ability to generate a composite view of medical-informatics and the real environment, streamlining the pathway for delivering patient-specific data. Consequently, AR was integrated within an orthopaedic setting by designing a system that captured and replicated the user- interface of a commercially available surgical robot onto a commercial head mounted see through display. Thus, a clinician could simultaneously view the operating-site and real- time informatics when carrying out an assisted patellofemoral-arthroplasty (PFA). The system was tested with 10 surgeons to examine its usability and impact on procedure- completion times when conducting simulated PFA on sawbone models. A statistically insignificant mean increase in procedure completion-time (+23.7s, p=0.240) was found, and the results of a post-operative qualitative-evaluation indicated a strongly positive consensus on the system, with a large majority of subjects agreeing the system provided value to the procedure without incurring noticeable physical discomfort. Overall, this study provides an encouraging insight into the high levels of engagement AR has with a clinical audience as well as its ability to enhance future generations of medical robotics.
Improved Patient Satisfaction Following TKA Using Intraoperative Computer Technology to Obtain Accurate Gap Balancing
Authors: Smith Austin , Eccles Christian , Bhimani Samrath , Denehy Kevin , Bhimani Rohat , Smith Langan , Malkani Arthur
Published: October 2019

Aims:

Approximately 20% of patients are dissatisfied with their total knee arthroplasty (TKA). Purpose of this study was to determine if patient satisfaction could be improved following TKA using computer technology to obtain the target alignment and precisely balanced gaps.

Patients & Methods:

75 consecutive patients undergoing primary robotic-arm assisted TKA (RA-TKA) with real-time intraoperative alignment and gap balancing information were compared with a prospective cohort of 75 consecutive patients undergoing primary TKA with manual jig-based instruments during the same time period. There were no differences between groups with age, gender, BMI, and ASA scores. TKA’s were performed by a single surgeon using same implant design, anesthesia and surgical protocols. Patient satisfaction survey using Knee Society (KSS) and Likert scoring system was obtained at 1-year follow-up.

Results:

Likert scoring system demonstrated 95% of patients in the computer technology group were either very satisfied or satisfied versus 75% in the manual instruments TKA group (p=0.005) at 1-year follow-up. Second question of the KSS which deals with pain at rest was significantly better in RA-TKA group (p=0.04). Fifth question which deals with recreational activities was also significantly improved in the RA-TKA group, p=0.02. RA-TKA group had a better average overall satisfaction score of 7.1 versus 6.4 in the manual instrument group, p=0.03.

Conclusion:

Using intraoperative computer technology to achieve the target alignment with flexion/extension gap balancing to within 1mm, a significant improvement in patient satisfaction was demonstrated compared to TKA using conventional manual jig-based instruments.
Spine Surface Segmentation from Ultrasound Using Multi-feature Guided CNN
Authors: Alsinan Ahmed , Vives Michael , Patel Vishal , Hacihaliloglu Ilker
Published: October 2019

Accurate, robust, and real-time segmentation of bone surfaces is an essential objective for ultrasound (US) guided computer assisted orthopedic surgery (CAOS) procedures. In this work, we present a convolutional neural network (CNN)-based technique for segmenting spine surfaces from in vivo US scans. Proposed design utilizes fusion of feature maps extracted from multimodal images to abate sensitivity to variations caused by imaging artifacts and low intensity bone boundaries. In particular, our multimodal inputs consist of B-mode US images and their corresponding local phase filtered counterparts. Validation studies performed on 261 in vivo US scans obtained from 10 subjects achieved a mean localization accuracy of 0.1 mm with an F-score of 97%. Comparison against state-of-the-art CNN networks show an improvement of 89% in bone surface localization accuracy.
Handle Navigation for a Smart Handheld Robot
Authors: Hung Shuo-Suei , Yen Ping-Lang
Published: October 2019

We demonstrated a miniature handheld robot in assisting the surgeon to create a tunnel during pedicle screw fixation. The robot is aimed at stabilizing the drill during penetrating the surface of a vertebra and reducing the drill drifting from the entry point caused by involuntary tremor. The handheld robot is consisted of a hexapod platform. The master control was designed to cooperate with the 6-DOF parallel slave robot. The human machine interface has been investigated for the drill to target the planned trajectory with the operator’s handle motion.
Total Hip Arthroplasty in Patients Younger than 35 Is Effective Regardless of Surgical Approach
Authors: Luthringer Tyler , Novikov David , Gabor Jonathan , Rudy Hayeem , Cizmic Zlatan , Mahure Siddharth , Schwarzkopf Ran , Davidovitch Roy , Vigdorchik Jonathan
Published: October 2019

PURPOSE: Indications for total hip arthroplasty (THA) are expanding to include increasingly younger patients, yet limited outcomes research has focused on this population. This study compares outcomes between the anterior and posterior approach, as well as between conventional and technology-assisted THA in patients under 35-years of age.

METHODS: Retrospective analysis of 139 primary THAs in 125 patients younger than 35-years old was conducted. Patients were divided into two cohorts: (1) anterior-THA and (2) posterior-THA. A posterior-THA sub-group analysis was performed to compare: (1) technology-assisted THA (tech-THA) versus (2) conventional-THA (con-THA). Demographics, perioperative data, radiographic and clinical outcomes were analyzed using Chi squared and unpaired student t-tests for categorical and continuous variables, respectively.

RESULTS: Of the 139 cases performed, 40 were anterior-THA and 99 were posterior-THA. The anterior-THA cohort had shorter mean surgical time (95.0±25.7 vs. 118.3±43.3 minutes; p<0.01), shorter hospital admissions (1.9±1.4 vs. 2.7±1.2 days; p<0.01), and lower estimated blood loss (343.4±164.1 vs. 438.0±272.8 mL; p<0.01) compared to the posterior-THA cohort. There were no significant differences in component positioning, limb length discrepancy, clinical outcomes or postoperative complications between cohorts. In the sub-group analysis, cup placement within Lewinnek’s Safe Zone was achieved in 78% of tech-THA versus 49% of con-THA (p<0.01). Need for revision THA was significantly higher among the con-THA group (9.4% vs. 0%; p<0.01).

CONCLUSION: There is no significant difference in outcomes between anterior- and posterior-THA among patients under 35-years of age, however, the anterior approach may promote earlier hospital discharge. Technological-assistance can improve component positioning and may reduce the rate of revision for posterior-THA in patients under 35-years old.
Patient specific surgical guide improve the accuracy of acetabular component placement in total hip arthroplasty with dysplastic acetabulum
Authors: Wu Peihui , Liao Weiming , Kang Yan
Published: October 2019

To investigate the accuracy of a novel 3D CT scan-based preoperative planning software linked to patient-specific instrumentation (PSI) for placing acetabular components planning in patients with acetabular dysplasia undergoing total hip arthroplasty (THA). A total of 30 consecutive patients were prospectively enrolled and the accuracy of placement of the acetabular component was measured using post- operative CT scans. There was good reproducibility of preoperative and postoperative position of reconstructed rotation center. The mean absolute deviation from the planned inclination and anteversion was 6.2° and 4.8°, respectively. In 90% of cases the planned target of +/-5° was achieved for both inclination and anteversion. And 95% of cases of planned target of +/-3mm were achieved for vertical height of rotation center. Accurate placement of the acetabular component can be achieved using patient-specific guides and is superior to free hand techniques.
Conservative Kinematic Alignment Strategies Report Higher Incidence of Mid-Term Pain Following TKA: a Retrospective Study
Authors: Wakelin Edgar , Twiggs Joshua , Fritsch Brett , Solomon Michael , Miles Brad
Published: October 2019

Kinematic alignment (KA) aims to restore the pre-arthritic geometry of the joint and has been shown to produce similar or improved outcomes compared to mechanical alignment (MA). However, there are significant challenges when attempting to restore outlier joint anatomy. This study sought to investigate how achieved TKA alignment correlates with 12 month patient outcomes. The study considered three categories of achieved TKA alignments: KA, MA, or conservative KA (restricting coronal component alignments to within 5° and combined coronal alignment to within 3° of neutral). 369 patients were analysed; each patient had pre- and post-operative CT scans and a 12-month postoperative Knee Osteoarthritis & Outcome Score (KOOS). From CT scans, component positions were measured, and patients were categorized to one of the three categories. The conservative KA group were least likely (76%) to reach the threshold KOOS Pain score set by the Patient Acceptable State Score (PASS); the full KA group was most likely (95%) to reach the threshold, whilst the MA group was in between these two groups (88%). These results demonstrated an increase in pain when the achieved alignment formed a compromise between a restorative and a reconstructive approach, and further suggests that conservative approaches to kinematic alignment may require a high level of discretion.
Comparison effect of Anatomical and Conventional tibial cut in post-operative radiographic parameter and clinical outcome of ankle joint in Computer assisted TKA.
Authors: Sriphirom Pornpavit , Chompoosaeng Thakrit , Boonton Bordin
Published: October 2019

In Total knee arthroplasty (TKA), not only knee joint affect when we restored limb alignment, but also other joints involved. Ankle joint is one of them. By changing in talar tilt, many studies shown this will lead to increase pain and disturb function of ankle. Patients may end up with unsatisfied result of TKA. Anatomical cut of tibia is use in order to avoid this problem.

To compare between pre- and post-operative talar tilt angle (TTA) and ankle clinical assessment by foot function index (FFI) and ankle-hindfoot index (AHI) after anatomical tibial cut (varus 3° with anatomical axis) and conventional tibial cut (perpendicular with anatomical axis) in computer-assisted total knee arthroplasty

This study was retrospective study. We collected data of 70 knees from 54 patients. 32 knees were done by anatomical cut. The rest were conventional cut. We evaluated at pre- and post-operative for TTA. At 12-month follow-up for TTA & ankle clinical assessment.

In conventional group, TTA was changed 2.33°(p<0.001) then 0.920(p=0.02) at follow up. In anatomical group, TTA was changed 2°(p=0.037) then 1.38°(p=1.56). Changing of TTA was not significantly different at post-operatively (p=0.76) and follow-up (p=0.98) between 2 groups. FFI& AHI were not significantly different between both groups.
Computer Navigation for Revision Total Hip Arthroplasty Reduces Dislocation Rates
Authors: Cizmic Zlatan , Carroll Kaitlin , Jerabek Seth , Paprosky Wayne , Sculco Peter , Della Valle Alejandro Gonzalez , Meere Patrick , McLawhorn Alexander , Schwarzkopf Ran , Boettner Friedrich , Mayman David , Vigdorchik Jonathan
Published: October 2019

INTRODUCTION: Computer-assisted hip navigation offers more accurate placement of hip components, potentially avoiding impingement, edge-loading, and dislocation; major causes of failure leading to revision THA. As such, the use of computer navigation may be particularly beneficial in the revision THA population. The purpose of this study was to determine if the use of computer-assisted hip navigation reduced the rate of dislocation in patients undergoing revision THA.

METHODS: A retrospective review of 72 patients undergoing computer-navigated revision THA between February 2016 and May 2017 was performed. Demographics, indications for revision, type of procedure performed, and postoperative complications were collected for all patients. Clinical follow-up was recorded at 3-months, 1-year and 2-years.

RESULTS: All 72 patients (48% female; 52% male) were included in the final analysis. Mean age of patients was 70.4 ± 11.2 years. Mean BMI was 26.4 ± 5.2 kg/m2. The most common indications for revision THA were instability (31%), aseptic loosening (29%), osteolysis/eccentric wear (18%), infection (11%), and miscellaneous (11%). At 3-months, 1-year, and 2-years there were no dislocations in any patients (0%). Compared to preoperative dislocation values, there was a significant reduction in the rate of dislocation with the use of computer-assisted hip navigation (31% vs. 0%; p<0.05).

DISCUSSION: Our study demonstrates a significant reduction in the rate of dislocation following revision THA with the use of computer navigation. Although the cause of postoperative dislocation is often multifactorial, the use of computer-assisted surgery may help to curtail femoral and acetabular malalignment in revision THA.
Integrating a Tracking Camera in the OR Using the IEEE 11073-SDC Communication Standard
Authors: Vossel Manuel , de La Fuente Matías , Wieschebrock Dario , Yilmaz Okan , Radermacher Klaus , Janß Armin
Published: October 2019

With the increasing spread of computer assisted surgery, more and more modern operating rooms are equipped with navigation systems, each coming with its own tracking camera. Since those cameras are part of the closed monolithic navigation system, they can’t be used for other applications than the one intended by the supplier. With the novel service oriented device connectivity standard (IEEE 11073-SDC), introduced by the OR.NET initiative (www.ornet.org), needless double procurements could be avoided and multiple systems could use the same camera that – similar to OR lights – could be installed as a standard equipment in each OR. This would decrease the cost-to-benefit ratio also of new applications that would currently as such not justify to acquire a proprietary tracking camera.

While the integration of a tracking camera to an open medical device IT network can open up for new applications, it should on the other hand not impair the usability and the safety of the navigation system. Therefore, a low latency must be guaranteed between tracking camera and navigational display.

This paper evaluates the integration of an atracsys fusionTrack 500 tracking camera into the OR.NETwork. The response time from a change in the real world to the reception of the corresponding data package is measured to determine the feasibility of an integra- tion without impairing current navigational tasks.

The results show that, as long as the underlying network infrastructure is not at its capacity limit, latencies below 60 ms are achieved. Therefore, the integration of a tracking camera for navigational tasks is feasible.
Accuracy, Inter- and Intra-Observer Reliability of a CT Alignment Measurement Protocol for Robotic-Arm Assisted Total Knee Arthroplasty
Authors: Zhang Jingwei , Persohn Scott , Bhowmik-Stoker Manoshi , Otto Jason , Paramasivam Meenakshisundaram , Wahdan Ahmad , Choplin Robert H. , Territo Paul
Published: October 2019

Component position and overall limb alignment following Total Knee Arthroplasty (TKA) have been shown to influence device survivorships and clinical outcomes. However, these parameters are often assessed through 2D radiographs after surgery, which can be prone to inaccuracy. The purpose of this paper is to develop a new method for 3D CT based overall limb alignment and component position measurements. The technique utilizes a new mathematical model to calculate prosthesis alignment from the coordinates of anatomical landmarks used in RATKA. The hypothesis is that the proposed technique demonstrated good accuracy, as well as low intra and inter-observer variability.

Two groups of patients (n=120 per group) underwent RATKA and conventional TKA at 4 imaging locations between October 2016 and August 2018, where they were recruited and consented for this prospective, non-randomized, multicenter study. CTs were collected 6 weeks post-operatively and analyzed using RATKA landmarks and the proposed technique. Measurements of 30 randomly selected cases were compared to the surgeons’ operative plan and component target positions for accuracy analysis. Two surgeons performed the same measurements separately for inter-observer variability analysis. One of the two surgeons repeated the measurements 30 days later to assess intra-observer variability.

Average measurement error of overall limb alignment, femoral and tibial component positions were less than 1 degree. Bland Altman plots analysis showed great reproducibility between observers. Correlation analysis showed low variability within observer, with slopes between 0.8 to 1.0 and R-squared > 0.8.

The proposed method demonstrated great accuracy to plan and low intra and inter-observer variability. This can be a great tool for RATKA studies where component accuracy is assessed using post-operative CTs.
How Surgeons Perform Total Knee Arthroplasty? A Global Appraisal of Computer-Assisted Surgeries
Authors: Bolch Charlotte , Dai Yifei , Jung Amaury , Hamad Cyril
Published: October 2019

This study investigated global variations in the surgical methods used with a contemporary CAOS system in TKA. Individual surgical profiles were identified from a database of technical reports on all TKA cases performed using a CAOS system. The profiles were divided into groups based on geographic regions (US, EU, and APAC), implant types (CR and PS), and application years. Differences were found in the surgeons’ preferences of surgical parameters and methods, reflecting the existence of variabilities in how surgeons perform TKA.