The Impact of Implant Design, Defect Size, and Type of Superstructure on the Accessibility of Nonsurgical and Surgical Approaches for the Treatment of Peri-implantitis

2017 ◽  
Vol 32 (2) ◽  
pp. 256-362 ◽  
Author(s):  
David Polak ◽  
Efrat Maayan ◽  
Tali Chackartchi
Keyword(s):  
Defect Size ◽  
Implant Design ◽  
Surgical Approaches ◽  
Design Defect ◽  
The Impact

scholarly journals P129 THORACIC VS. ABDOMINAL APPROACHES FOR DIAPHRAGMATIC HERNIA REPAIR: A NATIONWIDE STUDY OF CLINICAL OUTCOMES

2021 ◽  
Vol 108 (Supplement_8) ◽  
Author(s):  
Andrea Carolina Quiroga Centeno ◽  
Orlando Navas ◽  
Juan Paulo Serrano ◽  
Sergio Alejandro Gómez Ochoa
Keyword(s):  
Hospital Stay ◽  
Diaphragmatic Hernia ◽  
Hospital Costs ◽  
Length Of Hospital Stay ◽  
Hospital Charges ◽  
Surgical Approaches ◽  
Multivariate Logistic Regression Model ◽  
Abdominal Repair ◽  
Lower Health ◽  
The Impact

Abstract Aim “To compare the outcomes of different surgical approaches for diaphragmatic hernia (DH) repair.” Material and Methods “Adult patients with a principal admitting diagnosis of uncomplicated DH registered in the National Inpatient Sample in the period 2010-2015 were included. Patients with obstruction, gangrene, or congenital hernias were excluded. The primary outcome was in-hospital mortality. Secondary outcomes were the incidence of complications, length of stay, and hospital charges. A multivariate logistic regression model adjusted by age, sex, elective admission, comorbidities, and hospital characteristics was used to analyze the impact of the surgical approach on the evaluated outcomes.” Results “A total of 14910 patients with DH were included (median age 65 years, 74% women). Abdominal approaches were the most commonly performed (78.9% laparoscopy and 13.6% open). Patients that underwent open abdominal and thoracic repairs had a higher risk of complications (sepsis, pneumonia, surgical site infection, prolonged postoperative ileus, and acute myocardial infarction), longer hospital stay, higher total hospital costs, and a significantly higher risk of mortality (OR 2.62. 95% CI 1.59-4.30 and OR 4.60; 95% CI 2.37-8.91, respectively) compared to patients that underwent laparoscopic abdominal repair. Individuals whose DH repair was performed through thoracoscopy had a similar mortality risk to those who underwent laparoscopic abdominal repair (OR 0.87; 95% CI 0.11-6.43).” Conclusions “Nowadays, laparoscopy has become the most used approach for DH repair. In the present cohort, it was associated with better outcomes in terms of complications, length of hospital stay, and mortality, as well as lower health costs. Additional studies assessing hernia characteristics are required to validate this result.”

An Adaptable Ct-Derived 3D-Printed Alignment Fixture Minimizes Errors in Whole-Bone Biomechanical Testing

2021 ◽  
Author(s):  
Jordan V. Inacio ◽  
DanielleM Cristino ◽  
Michael W. Hast ◽  
Hannah Dailey
Keyword(s):  
Computational Models ◽  
Biomechanical Testing ◽  
Ct Scanning ◽  
Industrial Applications ◽  
Long Bone ◽  
Implant Design ◽  
Orthopaedic Implant ◽  
Test Frame ◽  
3D Printed ◽  
The Impact

Abstract Biomechanical testing of long bones can be subject to undesirable errors and uncertainty due to malalignment of specimens with respect to the mechanical axis of the test frame. To solve this problem, we designed a novel, customizable alignment and potting fixture for long bone testing. The fixture consisted of 3D-printed components modeled from specimen-specific CT scans to achieve a predetermined specimen alignment. We demonstrated the functionality of this fixture by comparing benchtop torsional test results to specimen-matched finite element models and found a strong and statistically significant correlation (R2 = 0.9536, p < 0.001). Additional computational models estimated the impact of malalignment on mechanical behavior in both torsion and axial compression. Results confirmed that torsion testing is relatively robust to alignment artifacts, with absolute percent errors less than 8% in all malalignment scenarios. In contrast, axial testing was highly sensitive to setup errors, experiencing absolute percent errors up to 40% with off-center malalignment and up to 130% with angular malalignment. This suggests that whenever appropriate, torsion tests should be used preferentially as a summary mechanical measure. When more challenging modes of loading are required, pre-test clinical-resolution CT scanning can be effectively used to create potting fixtures that allow for precise pre-planned specimen alignment. This may be particularly important for more sensitive biomechanical tests (e.g. axial compressive tests) that may be needed for industrial applications, such as orthopaedic implant design.

THE IMPACT OF AUDITORY NERVE EXPERIMENTS ON COCHLEAR IMPLANT DESIGN

1983 ◽  
Vol 405 (1 Cochlear Pros) ◽  
pp. 114-121 ◽  
Author(s):  
N. Y. S. Kiang ◽  
E. M. Keithley ◽  
M. C. Liberman
Keyword(s):  
Cochlear Implant ◽  
Auditory Nerve ◽  
Implant Design ◽  
The Impact

High Quality Non-Ferrous Die Castings Dependence on Die Design – A Review of the Use of Die Filling and Casting Solidification Simulation Results for Successful, Effective and Practical Die Designs

2014 ◽  
Vol 1019 ◽  
pp. 143-151
Author(s):  
Carl J. Reinhardt ◽  
Morris Murray ◽  
Isaac Bohlken
Keyword(s):  
High Pressure ◽  
Cost Effective ◽  
Die Design ◽  
Dynamics Simulation ◽  
High Quality ◽  
Design Defect ◽  
Simulation Results ◽  
Die Castings ◽  
Pressure Die Casting ◽  
The Impact

High Quality Cost Effective Die Castings rely to a large extent on successful, effective and practical die design. A review is carried out of some runner and gate designs which resulted in successful high quality castings. Some High Pressure and Gravity cast casting are evaluated. Simulation results for evaluating the impact on the flow during filling due to Runner Geometries, Gate Geometries and positions as well as venting, overflows or risers are discussed. Thermal intervention through the use of internal thermal channels are also evaluated through the use of simulation results. The paper centres on a discussion of analysis of simulation results, predicting defects which impact on some aspects of surface finish and porosity. A case study is presented showing the value of following and taking heed of lessons learnt from simulation results, to carry out die designs with reduced reliance on simulation. Index Terms: South African Foundries, High Pressure Die Casting, Computerised Fluid Dynamics Simulation, Die Design, Defect Reduction.

The Impact of Computed Tomography on Decision Making in Tibial Plateau Fractures

2018 ◽  
Vol 31 (10) ◽  
pp. 1007-1014 ◽  
Author(s):  
Marcello Castiglia ◽  
Marcello Nogueira-Barbosa ◽  
Andre Messias ◽  
Rodrigo Salim ◽  
Fabricio Fogagnolo ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Decision Making ◽  
Surgical Approach ◽  
Tibial Plateau ◽  
Classification Systems ◽  
Tibial Plateau Fractures ◽  
Surgical Approaches ◽  
Plain Radiographs ◽  
Schatzker Classification ◽  
The Impact

AbstractSchatzker introduced one of the most used classification systems for tibial plateau fractures, based on plain radiographs. Computed tomography brought to attention the importance of coronal plane-oriented fractures. The goal of our study was to determine if the addition of computed tomography would affect the decision making of surgeons who usually use the Schatzker classification to assess tibial plateau fractures. Image studies of 70 patients who sustained tibial plateau fractures were uploaded to a dedicated homepage. Every patient was linked to a folder which contained two radiographic projections (anteroposterior and lateral), three interactive videos of computed tomography (axial, sagittal, and coronal), and eight pictures depicting tridimensional reconstructions of the tibial plateau. Ten attending orthopaedic surgeons, who were blinded to the cases, were granted access to the homepage and assessed each set of images in two different rounds, separated to each other by an interval of 2 weeks. Each case was evaluated in three steps, where surgeons had access, respectively to radiographs, two-dimensional videos of computed tomography, and three-dimensional reconstruction images. After every step, surgeons were asked to present how would they classify the case using the Schatzker system and which surgical approaches would be appropriate. We evaluated the inter- and intraobserver reliability of the Schatzker classification using the Kappa concordance coefficient, as well as the impact of computed tomography in the decision making regarding the surgical approach for each case, by using the chi-square test and likelihood ratio. The interobserver concordance kappa coefficients after each assessment step were, respectively, 0.58, 0.62, and 0.64. For the intraobserver analysis, the coefficients were, respectively, 0.76, 0.75, and 0.78. Computed tomography changed the surgical approach selection for the types II, V, and VI of Schatzker (p < 0.01). The addition of computed tomography scans to plain radiographs improved the interobserver reliability of Schatzker classification. Computed tomography had a statistically significant impact in the selection of surgical approaches for the lateral tibial plateau.

The impact of capitellar arthroplasty on elbow contact mechanics: Implications for implant design

2011 ◽  
Vol 26 (5) ◽  
pp. 458-463 ◽  
Author(s):  
M.T. Sabo ◽  
H. Shannon ◽  
J. Ng ◽  
L.M. Ferreira ◽  
J.A. Johnson ◽  
...  
Keyword(s):  
Contact Mechanics ◽  
Implant Design ◽  
The Impact

Automated Virtual Placement and Evaluation of Tibial Components for Knee Arthroplasty

2011 ◽  
Author(s):  
Yifei Dai ◽  
Mary S. S. Wentorf ◽  
Jeffrey E. Bischoff
Keyword(s):  
Knee Arthroplasty ◽  
Rotational Alignment ◽  
Implant Design ◽  
Rotational Axis ◽  
Rotational Malalignment ◽  
Tibial Tray ◽  
Key Factor ◽  
Total Knee ◽  
The Impact ◽  
Good Coverage

The ability of tibial tray component shapes to appropriately fit boney geometry is an important aspect of implant design in total knee arthroplasty. Overhang of components in the knee has been associated with soft tissue damage and joint pain [1,2]. Good coverage establishes stability through adequate cortical bone support of the tray component, and reduces the likelihood of loosening and subsidence [3–5], and therefore serves as a key factor in component fixation, especially in those that rely on biological growth into porous component backings such as Trabecular Metal™ Material. More importantly, rotational malalignment of the tibial tray can disrupt the natural kinematics and implant longevity [6]. Previous studies investigated coverage of multiple tibial trays on digitized bone resection contours [1,7]. However the methodology for rotational alignment during implantation was not identified. Although rotational alignment has been investigated in numerous studies, most of the studies were carried out by either investigating the impact of malalignment [6], or assessing different definitions of the tibia rotational axis [8]. No correlation between the size of the rotational alignment window and the amount of coverage has been shown.

Cartilage Thickness Distribution Affects Computational Model Predictions of Cervical Spine Facet Contact Parameters

2010 ◽  
Vol 133 (1) ◽  
Author(s):  
Wesley Womack ◽  
Ugur M. Ayturk ◽  
Christian M. Puttlitz
Keyword(s):  
Finite Element ◽  
Cervical Spine ◽  
Articular Cartilage ◽  
Cartilage Thickness ◽  
Implant Design ◽  
Lower Cervical Spine ◽  
Model Predictions ◽  
Geometric Representations ◽  
Spatially Varying ◽  
The Impact

With motion-sparing disk replacement implants gaining popularity as an alternative to anterior cervical discectomy and fusion (ACDF) for the treatment of certain spinal degenerative disorders, recent laboratory investigations have studied the effects of disk replacement and implant design on spinal kinematics and kinetics. Particularly relevant to cervical disk replacement implant design are any postoperative changes in solid stresses or contact conditions in the articular cartilage of the posterior facets, which are hypothesized to lead to adjacent-level degeneration. Such changes are commonly investigated using finite element methods, but significant simplification of the articular geometry is generally employed. The impact of such geometric representations has not been thoroughly investigated. In order to assess the effects of different models of cartilage geometry on load transfer and contact pressures in the lower cervical spine, a finite element model was generated using cadaver-based computed tomography imagery. Mesh resolution was varied in order to establish model convergence, and cadaveric testing was undertaken to validate model predictions. The validated model was altered to include four different geometric representations of the articular cartilage. Model predictions indicate that the two most common representations of articular cartilage geometry result in significant reductions in the predictive accuracy of the models. The two anatomically based geometric models exhibited less computational artifact, and relatively minor differences between them indicate that contact condition predictions of spatially varying thickness models are robust to anatomic variations in cartilage thickness and articular curvature. The results of this work indicate that finite element modeling efforts in the lower cervical spine should include anatomically based and spatially varying articular cartilage thickness models. Failure to do so may result in loss of fidelity of model predictions relevant to investigations of physiological import.

The impact of transferred vascularized toe joint length on motion arc of reconstructed finger proximal interphalangeal joints: a cadaveric study

2017 ◽  
Vol 42 (8) ◽  
pp. 789-793 ◽  
Author(s):  
Chung-Chen Hsu ◽  
Charles Yuen Yung Loh ◽  
Dennis Kao ◽  
Steven L. Moran ◽  
Yu-Te Lin
Keyword(s):  
Proximal Interphalangeal Joint ◽  
Defect Size ◽  
Interphalangeal Joint ◽  
Cadaveric Study ◽  
Equal Length ◽  
Segment Length ◽  
Joint Reconstruction ◽  
Bony Segment ◽  
The Impact ◽  
Joint Length

Vascularized toe joint transfer for finger proximal interphalangeal joint reconstruction can result in sub-optimal arc of motion and extension lag due to inappropriate intercalated bony segment length. We investigated the impact of intercalated segment length on passive arc of motion and extension lag of the reconstructed proximal interphalangeal joint. Cadaveric intercalated joint grafts were harvested from lesser toes and transferred to cadaveric fingers. The pre-determined finger proximal interphalangeal joint defect size was 2 cm. Three different intercalated segment lengths were inserted and resulting proximal interphalangeal joint arc of motion and extension lag were measured. The average arc of motion of finger proximal interphalangeal joints was 81° and 54° for toe proximal interphalangeal joints. Long intercalated segments had an average arc of motion of 30° with 32° extension lag. Equal-length intercalated segments had an average 49° arc of motion with 15° extension lag. Short intercalated segments had an average arc of motion of 71° with 8° extension lag. Shorter intercalated segments provide the greatest reduction in extension lag.

scholarly journals Femoral Trochlear Groove Recreation Following TKA Correlates with Improved Patient Reported Outcome

10.29007/8hbf ◽  
2019 ◽  
Author(s):  
Joshua Twiggs ◽  
Edgar Wakelin ◽  
Stephen McMahon ◽  
Brad Miles
Keyword(s):  
Patient Outcome ◽  
Patient Reported Outcome ◽  
Ct Scans ◽  
Implant Design ◽  
Target Component ◽  
Trochlear Groove ◽  
Post Surgery ◽  
Patient Reported ◽  
Total Knee ◽  
The Impact

Femoral component recreation of the trochlear groove is a major factor in determining post-operative patello-femoral tracking. Significant variation arises in recreation of the trochlear groove when a standardised implant design is applied to variable patient anatomy and alignment. However, the impact of variation on patient outcome is not well understood. This study sought to understand whether the accuracy of recreation of the trochlear groove drives patient outcome following total knee arthroplasty (TKA). 430 TKA patients were analysed; patients had pre- and post-operative CT scans and postoperative Knee Injury &amp; Osteoarthritis Outcome (KOOS) scores at 6 months post- surgery. Based on the pre- and post-operative CT scans, femoral trochlear groove positioning and the post-surgery “build-up” of the medial and lateral apex either side of the groove were modeled and measured. Correlations between changes to this native morphology and KOOS scores were statistically tested. Patients who had increased implant build-up on the trochlear lateral apex had a worse outcome (correlation with KOOS Pain score: r = -0.2, p = 0.03), and this was found to be driven by impairment when straightening and pain when bending. The results suggest that reducing the proximal lateral apex of the trochlear groove post-implantation leads to improved patient outcomes when straightening the knee, with implications for both implant design and target component placement.

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