scholarly journals Intraoperative three-dimensional imaging in ankle syndesmotic reduction.

2021 ◽  
Author(s):  
Markus Beck ◽  
Manuela Brunk ◽  
Alice Wichelhaus ◽  
Thomas Mittlmeier ◽  
Robert Rotter
Keyword(s):  
Ankle Joint ◽  
Computer Tomography ◽  
Revision Rate ◽  
Three Dimensional ◽  
Image Intensifier ◽  
Tibiofibular Syndesmosis ◽  
3D Scan ◽  
Osteosynthesis Material ◽  
Ankle Joints ◽  
3D Scans

Abstract Background: Injuries of the distal syndesmosis in ankle fractures are traditionally treated with a temporary adjusting screw fixation. Conventional fluoroscopic and X-ray examinations cannot reliably diagnose malpositions of the fixed tibiofibular syndesmosis. Postoperative computer tomography allows a reliable control of the transfixed region.The aim of the retrospective single-study was to clarify whether an intraoperative 3D image intensifier examination can detect malpositions of the syndesmosis already intraoperatively and whether the examination has an influence on the postoperative revision rate.Methods: In 200 patients with tibiofibular syndesmosis injuries, an intraoperative 3D scan was performed after reduction of the distal tibiofibular syndesmosis and placement of the adjusting screw. Postoperative computer tomography of both ankle joints was performed in all patients. Results: 15% of all intraoperative 3D scans (30 patients) showed a finding requiring correction in the area of the ankle joint. In 7% of the cases, a malposition of the fibula in the tibial incisura requiring correction was found. Further corrections were necessary due to the extent and position of the osteosynthesis material (7%) and for the removal of joint bodies (1%). Postoperative computer tomographies of the ankle joints showed no deformities requiring revision. Conclusion: An intraoperative 3D scan allows a reliable assessment of the injured ankle region and reduces the postoperative revision rate. This makes a postoperative routine CT examination of the ankle joint dispensable.

scholarly journals Intraoperative three-dimensional imaging in ankle syndesmotic reduction.

2020 ◽  
Author(s):  
Markus Beck ◽  
Manuela Brunk ◽  
Alice Wichelhaus ◽  
Thomas Mittlmeier ◽  
Robert Rotter
Keyword(s):  
Ankle Joint ◽  
Computer Tomography ◽  
Revision Rate ◽  
Three Dimensional ◽  
Image Intensifier ◽  
Tibiofibular Syndesmosis ◽  
3D Scan ◽  
Osteosynthesis Material ◽  
Ankle Joints ◽  
3D Scans

Abstract Background: Injuries of the distal syndesmosis in ankle fractures are traditionally treated with a temporary adjusting screw fixation. Conventional fluoroscopic and X-ray examinations cannot reliably diagnose malpositions of the fixed tibiofibular syndesmosis. Postoperative computer tomography allows a reliable control of the transfixed region.The aim of the retrospective single-study was to clarify whether an intraoperative 3D image intensifier examination can detect malpositions of the syndesmosis already intraoperatively and whether the examination has an influence on the postoperative revision rate. Methods: In 200 patients with tibiofibular syndesmosis injuries, an intraoperative 3D scan was performed after reduction of the distal tibiofibular syndesmosis and placement of the adjusting screw. Postoperative computer tomography of both ankle joints was performed in all patients. Results: 15% of all intraoperative 3D scans (30 patients) showed a finding requiring correction in the area of the ankle joint. In 7% of the cases, a malposition of the fibula in the tibial incisura requiring correction was found. Further corrections were necessary due to the extent and position of the osteosynthesis material (7%) and for the removal of joint bodies (1%). Postoperative computer tomographies of the ankle joints showed no deformities requiring revision. Conclusion: An intraoperative 3D scan allows a reliable assessment of the injured ankle region and reduces the postoperative revision rate. This makes a postoperative routine CT examination of the ankle joint dispensable.

scholarly journals Intraoperative Three-Dimensional Imaging in Ankle Syndesmotic Reduction.

2020 ◽  
Author(s):  
Markus Beck ◽  
Manuela Brunk ◽  
Alice Wichelhaus ◽  
Thomas Mittlmeier ◽  
Robert Rotter
Keyword(s):  
Computer Tomography ◽  
Three Dimensional ◽  
Image Intensifier ◽  
Tibiofibular Syndesmosis ◽  
X Ray ◽  
3D Scan ◽  
Osteosynthesis Material ◽  
Reliable Assessment ◽  
Ankle Joints ◽  
3D Scans

Abstract PurposeInjuries of the distal syndesmosis in ankle fractures are traditionally treated with a temporary adjusting screw fixation. Conventional fluoroscopic and X-ray examinations cannot reliably diagnose malpositions of the fixed tibiofibular syndesmosis. Postoperative computer tomography allows a reliable control of the transfixed region. The aim of the study was to clarify whether an intraoperative 3D image intensifier examination can detect malpositions of the syndesmosis already intraoperatively and whether the examination has an influence on the postoperative revision rate.MethodsIn 200 patients with tibiofibular syndesmosis injuries, an intraoperative 3D scan was performed after reduction of the distal tibiofibular syndesmosis and placement of the adjusting screw. Postoperative computer tomography of both ankle joints was performed in all patients.Results15% of all intraoperative 3D scans (30 patients) showed a finding requiring correction in the area of the ankle fork. In 7% of the cases, a malposition of the fibula in the tibial incisura requiring correction was found. Further corrections were necessary due to the extent and position of the osteosynthesis material (7%) and for the removal of joint bodies (1%). Postoperative computer tomographies of the ankle joints showed no deformities requiring revision.ConclusionAn intraoperative 3D scan allows a reliable assessment of the injured ankle region and reduces the postoperative revision rate. This makes a postoperative routine CT examination of the ankle joint dispensable.

Three-Dimensional Analysis of Ankle Instability after Tibiofibular Syndesmosis Injuries

2007 ◽  
Vol 36 (2) ◽  
pp. 348-352 ◽  
Author(s):  
Atsushi Teramoto ◽  
Hideji Kura ◽  
Eiichi Uchiyama ◽  
Daisuke Suzuki ◽  
Toshihiko Yamashita
Keyword(s):  
Ankle Joint ◽  
Ankle Instability ◽  
External Rotation ◽  
Tracking System ◽  
Three Dimensional ◽  
Traction Force ◽  
Tibiofibular Syndesmosis ◽  
Tibiofibular Ligament ◽  
Distal Tibiofibular Syndesmosis ◽  
Fresh Frozen

Background Rupture of the distal tibiofibular syndesmosis commonly occurs with extreme external rotation. Most studies of syndesmosis injuries have concentrated only on external rotation instability of the ankle joint and have not examined other defects. Hypothesis Syndesmosis injuries cause multidirectional ankle instability. Study Design Controlled laboratory study. Methods Ankle instability caused by distal tibiofibular syndesmosis injuries was examined using 7 normal fresh-frozen cadaveric legs. The anterior tibiofibular ligament, interosseous membrane, and posterior tibiofibular ligament, which compose the distal tibiofibular syndesmosis, were sequentially cut. Anterior, posterior, medial, and lateral traction forces, as well as internal and external rotation torque, were applied to the tibia; the diastasis between the tibia and fibula and the angular motion among the tibia, fibula, and talus were measured using a magnetic tracking system. Results A medial traction force with a cut anterior tibiofibular ligament significantly increased the diastasis from 1.1 to 2.0 mm ( P = .001) and talar tilt angles from 9.6° to 15.2° ( P < .001). External rotation torque significantly increased the diastasis from 0.5 to 1.8 mm ( P= .009) with a complete cut; external rotation torque also significantly increased rotational angles from 7.1° to 9.4° ( P = .05) with an anterior tibiofibular ligament cut. Conclusion Syndesmosis injuries caused ankle instability with medial traction force and external rotation torque to the tibia. Clinical Relevance Both physicians and athletes should be aware of inversion instability of the ankle joint caused by tibiofibular syndesmosis injuries.

scholarly journals Is Micro X-ray Computer Tomography a Suitable Non-Destructive Method for the Characterisation of Dental Materials?

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1271
Author(s):  
Andreas Koenig ◽  
Leonie Schmohl ◽  
Johannes Scheffler ◽  
Florian Fuchs ◽  
Michaela Schulz-Siegmund ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Computer Tomography ◽  
Mechanical Performance ◽  
Dental Materials ◽  
Three Dimensional ◽  
X Rays ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Multiple Measurements ◽  
High Doses

The aim of the study was to investigate the effect of X-rays used in micro X-ray computer tomography (µXCT) on the mechanical performance and microstructure of a variety of dental materials. Standardised bending beams (2 × 2 × 25 mm3) were forwarded to irradiation with an industrial tomograph. Using three-dimensional datasets, the porosity of the materials was quantified and flexural strength was investigated prior to and after irradiation. The thermal properties of irradiated and unirradiated materials were analysed and compared by means of differential scanning calorimetry (DSC). Single µXCT measurements led to a significant decrease in flexural strength of polycarbonate with acrylnitril-butadien-styrol (PC-ABS). No significant influence in flexural strength was identified for resin-based composites (RBCs), poly(methyl methacrylate) (PMMA), and zinc phosphate cement (HAR) after a single irradiation by measurement. However, DSC results suggest that changes in the microstructure of PMMA are possible with increasing radiation doses (multiple measurements, longer measurements, higher output power from the X-ray tube). In summary, it must be assumed that X-ray radiation during µXCT measurement at high doses can lead to changes in the structure and properties of certain polymers.

Muscle Function and Coordination of Stair Ascent

2017 ◽  
Vol 140 (1) ◽  
Author(s):  
Nicole G. Harper ◽  
Jason M. Wilken ◽  
Richard R. Neptune
Keyword(s):  
Three Dimensional ◽  
Gluteus Maximus ◽  
Gluteus Medius ◽  
Patient Specific ◽  
Functional Roles ◽  
Stair Ascent ◽  
Lower Limb Muscles ◽  
Ankle Joints ◽  
Community Environments ◽  
Antagonistic Muscles

Stair ascent is an activity of daily living and necessary for maintaining independence in community environments. One challenge to improving an individual's ability to ascend stairs is a limited understanding of how lower-limb muscles work in synergy to perform stair ascent. Through dynamic coupling, muscles can perform multiple functions and require contributions from other muscles to perform a task successfully. The purpose of this study was to identify the functional roles of individual muscles during stair ascent and the mechanisms by which muscles work together to perform specific subtasks. A three-dimensional (3D) muscle-actuated simulation of stair ascent was generated to identify individual muscle contributions to the biomechanical subtasks of vertical propulsion, anteroposterior (AP) braking and propulsion, mediolateral control and leg swing. The vasti and plantarflexors were the primary contributors to vertical propulsion during the first and second halves of stance, respectively, while gluteus maximus and hamstrings were the primary contributors to forward propulsion during the first and second halves of stance, respectively. The anterior and posterior components of gluteus medius were the primary contributors to medial control, while vasti and hamstrings were the primary contributors to lateral control during the first and second halves of stance, respectively. To control leg swing, antagonistic muscles spanning the hip, knee, and ankle joints distributed power from the leg to the remaining body segments. These results compliment previous studies analyzing stair ascent and provide further rationale for developing targeted rehabilitation strategies to address patient-specific deficits in stair ascent.

scholarly journals CUSTOMIZED GUIDE FOR FEMORAL COMPONENT POSITIONING IN HIP RESURFACING ARTHROPLASTY

2017 ◽  
Vol 25 (2) ◽  
pp. 103-106
Author(s):  
Chaturong Pornrattanamaneewong ◽  
Rapeepat Narkbunnam ◽  
Keerati Chareancholvanich
Keyword(s):  
Femoral Neck ◽  
Three Dimensional ◽  
Posterior Part ◽  
Image Intensifier ◽  
Hip Resurfacing ◽  
Three Dimensional Model ◽  
Level Of Evidence ◽  
Hip Resurfacing Arthroplasty ◽  
Femoral Neck Axis ◽  
Resurfacing Arthroplasty

ABSTRACT Objective: To prove the accuracy of a customized guide developed according to our method. Methods: This customized guide was developed from a three-dimensional model of proximal femur reconstructed using computed tomography data. Based on the new technique, the position of the guide pin insertion was selected and adjusted using the reference of the anatomical femoral neck axis. The customized guide consists of a hemispheric covering designed to fit the posterior part of the femoral neck. The performance of the customized guide was tested in eight patients scheduled for total hip arthroplasty. The stability of the customized guide was assessed by orthopedic surgeons. An intraoperative image intensifier was used to assess the accuracy. Results: The customized guide was stabilized with full contact and was fixed in place in all patients. The mean angular deviations in relation to the what was planned in anteroposterior and lateral hip radiographs were 0.5º ± 1.8º in valgus and 1.0º ± 2.4º in retroversion, respectively. Conclusion: From this pilot test, the authors suggest that the proposed technique could be applied as a customized guide to the positioning device for hip resurfacing arthroplasty with acceptable accuracy and user-friendly interface. Level of Evidence IV, Cases Series.

scholarly journals TightCap: 3D Human Shape Capture with Clothing Tightness Field

2022 ◽  
Vol 41 (1) ◽  
pp. 1-17
Author(s):  
Xin Chen ◽  
Anqi Pang ◽  
Wei Yang ◽  
Peihao Wang ◽  
Lan Xu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Ground Truth ◽  
Data Driven ◽  
Optimization Scheme ◽  
High Quality ◽  
3D Scan ◽  
Multi Stage ◽  
Geometry Image

In this article, we present TightCap, a data-driven scheme to capture both the human shape and dressed garments accurately with only a single three-dimensional (3D) human scan, which enables numerous applications such as virtual try-on, biometrics, and body evaluation. To break the severe variations of the human poses and garments, we propose to model the clothing tightness field—the displacements from the garments to the human shape implicitly in the global UV texturing domain. To this end, we utilize an enhanced statistical human template and an effective multi-stage alignment scheme to map the 3D scan into a hybrid 2D geometry image. Based on this 2D representation, we propose a novel framework to predict clothing tightness field via a novel tightness formulation, as well as an effective optimization scheme to further reconstruct multi-layer human shape and garments under various clothing categories and human postures. We further propose a new clothing tightness dataset of human scans with a large variety of clothing styles, poses, and corresponding ground-truth human shapes to stimulate further research. Extensive experiments demonstrate the effectiveness of our TightCap to achieve the high-quality human shape and dressed garments reconstruction, as well as the further applications for clothing segmentation, retargeting, and animation.

scholarly journals Determination of the Optimal Syndesmosis Fixation Angle Using Mortise View of The Ankle Joint

2021 ◽  
Author(s):  
Oğuzhan Tanoğlu ◽  
İzzet Özay Subaşı ◽  
Mehmet Burak Gökgöz
Keyword(s):  
Ankle Joint ◽  
Articular Surface ◽  
Three Dimensional ◽  
Vertical Plane ◽  
Functional Results ◽  
Practical Method ◽  
Medial Malleolus ◽  
Significant Difference ◽  
Horizontal View ◽  
Mortise View

Background: Syndesmosis is an important soft tissue component supporting the ankle stability and commonly injured accompanying with ankle fractures. The accurate reduction and fixation of syndesmosis is essential to obtain better functional results. Therefore, we aimed to find a practical method using the mortise view of ankle to determine the optimal syndesmosis fixation angle intraoperatively. Methods: We randomly selected 200 adults (100 women and 100 men) between 18 - 60 years of age. Three-dimensional anatomical models of tibia and fibula were created using Materialise MIMICS 21. We created a best fit plane on articular surface of medial malleolus and a ninety degrees vertical plane to medial malleolus plane. We determined two splines on cortical borders of tibia and fibula distant from the most superior point of ankle joint in horizontal view. We created two spheres that fit to the predefined splines. The optimal syndesmosis fixation angle was determined measuring the angle between the line connecting the center points of spheres, and the ninety degrees vertical plane to medial malleolus plane. Results: We observed no statistically significant difference between gender groups in terms of optimal syndesmosis fixation angles. The mean age of our study population was 47.1 {plus minus} 10.5. The optimal syndesmosis fixation angle according to mortise view was found as 21 {plus minus} 4.3 degrees. Conclusions: We determined the optimal syndesmosis fixation angle as 21 {plus minus} 4.3 degrees in accordance with the mortise view of ankle. The surgeon could evaluate the whole articular surface of ankle joint with the medial and lateral syndesmotic space in mortise view accurately and at the same position syndesmosis fixation could be performed at 21 {plus minus} 4.3 degrees.

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