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Background: Paranasal augmentation has been a popular approach in restoring Asian patients' lateral profile. Irregular surface in the surgical area emphasizes the importance of morphological evidence for the preoperative evaluation and the design of paranasal implants. Methods: We retrospectively collected craniofacial computer tomography scans of patients in the department of plastic surgery from 2020 to 2022. The imaging data were imported to Mimics (version 20.0; Materialize, Leuven, Belgium) for three-dimensional reconstruction. Measurements of osteal nasal base were performed in 3-matics (version 12.0; Materialize). The severity of paranasal concavity was graded by a senior doctor to study the correlation with measured variables. Results: Fifty-seven patients with a median age of 27 years (IQR: 22–33) were included in the study. For design of paranasal implants, the lengths of both lower and lateral edge were measured for reference. In the regression analysis, the alar base-alveolar process angle was significantly associated with the degrees of paranasal concavity (OR = 1.222, p = 0.00001). Conclusions: Morphological data of osteal nasal base were measured and presented in the current study. The analysis supported that alar base-alveolar process angle be used for preoperative grading and evaluation to help guiding treatment decisions. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

Introduction: Cementless fixation has become increasingly popular in hip arthroplasty due to its shorter operation time, easier technique, biologic fixation, and avoidance of bone cement implantation syndrome compared to cemented fixation. However, intraoperative periprosthetic femoral fracture (IOPFx) is a disconcerting complication during cementless hip arthroplasty. Our purpose was to identify the features of cementless stem that increase the risk of IOPFx during primary hip arthroplasty. Materials and methods: We retrospectively reviewed all 4806 hip arthroplasties that was performed in a single institution from May 2003 to December 2020. Age at the index arthroplasty, sex, body mass index, physical status, ambulatory function, side of the operation, operational history, cause of the index arthroplasty, type of arthroplasty, surgical approach, surgeon, implant information, and events during the operation were investigated. The shoulder geometry and length of stem were also reviewed. The event of interest was narrowed down to IOPFx among various records of intraoperative events. Results: We found IOPFx of 2.6% among all the hips operated with cementless stem. In the multivariable analysis, female (OR = 1.52), childhood hip disease (OR = 2.30), stove-pipe femur (OR = 2.43), combined approach (OR = 2.60), and standard length of stem (OR = 1.59) were found to be significant risk factors of IOPFx. Conclusions: In conclusion, a stem with a standard length is significantly associated with risk of IOPFx compared to a shortened stem. These findings highlight the importance of careful consideration in terms of the risk of IOPFx when standard length cementless stem is chosen. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Digital technologies are continuously improving the accuracy and quality of maxillofacial prosthetics, but their impact on patients remains unclear. This cross‐sectional study aimed to analyze the impact of facial prosthetics service provision, patients' perception, and digital technology on prostheses construction. Materials and Methods: All patients who presented for evaluation and management of facial defects between January 2021 and December 2021 at the ENT clinic were eligible for study enrollment. Patients requiring prosthetic reconstruction of their missing facial parts were included in the study. Forty‐five questionnaires were delivered, inquiring about the patients' prosthetic demographics, prosthesis manufacture using 3D technologies, and their perceptions and attitudes. Results: A total of 37 patients responded (29 males, eight females; mean age 20.50 years). The congenital cause was the highest among other causes (p = 0.001) with auricular defects being the highest (p = 0.001). A total of 38 prostheses were constructed and 17 prostheses were retained by 36 craniofacial implants (p = 0.014). The auricular and orbital implants success rates were 97% and 25%, respectively. The implant locations were digitally planned pre‐operatively. Digital 3D technologies of defect capture, data designing, and 3D modeling were used and perceived as helpful and comfortable (p = 0.001). Patients perceived their prosthesis as easy to handle, suited them, and they felt confident with it (p = 0.001). They wore it for more than 12 h daily (p = 0.001). They were not worried that it would be noticed, and found it comfortable and stable during various activities (p = 0.001). Implant‐retained prosthesis patients were more satisfied with it, and found it easy to handle and stable (p = 0.001). Conclusions: Congenital defects are the main cause of facial defects in the study country. The overall acceptance of maxillofacial prostheses was good, showing high patient perception and satisfaction. Ocular and implant‐retained silicone prostheses are better handled, more stable, and the latter is more satisfying than traditional adhesive prostheses. Digital technologies save time and effort invested in manufacturing facial prostheses. [ABSTRACT FROM AUTHOR]

Background: The prosthetic socket is a key component that influences prosthesis satisfaction, with a poorly fitting prosthetic socket linked to prosthesis abandonment and reduced community participation. This paper reviews adjustable socket designs, as they have the potential to improve prosthetic fit and comfort through accommodating residual limb volume fluctuations and alleviating undue socket pressure. Methods: Systematic literature and patent searches were conducted across multiple databases to identify articles and patents that discussed adjustable prosthetic sockets. The patents were used to find companies, organisations, and institutions who currently sell adjustable sockets or who are developing devices. Results: 50 literature articles and 63 patents were identified for inclusion, representing 35 different designs used in literature and 16 commercially available products. Adjustable sockets are becoming more prevalent with 73% of publications (literature, patents, and news) occurring within the last ten years. Two key design characteristics were identified: principle of adjustability (inflatable bladders, moveable panels, circumferential adjustment, variable length), and surface form (conformable, rigid multi-DOF, and rigid single DOF). Inflatable bladders contributed to 40% of literature used designs with only one identified commercially available design (n = 16) using this approach. Whereas circumferential adjustment designs covered 75% of identified industry designs compared to only 36% of literature devices. Clinical studies were generally small in size and only 17.6% of them assessed a commercially available socket. Discussion: There are clear differences in the design focus taken by industry and researchers, with justification for choice of design and range of adjustment often being unclear. Whilst comfort is often reported as improved with an adjustable socket, the rationale behind this is not often discussed, and small study sizes reduce the outcome viability. Many adjustable sockets lack appropriate safety features to limit over or under tightening, which may present a risk of tissue damage or provide inadequate coupling, affecting function and satisfaction. Furthermore, the relationship between design and comfort or function are rarely investigated and remain a significant gap in the literature. Finally, this review highlights the need for improved collaboration between academia and industry, with a strong disconnect observed between commercial devices and published research studies. [ABSTRACT FROM AUTHOR]

Objective: To assess actual data on the safety, effectiveness, and hemodynamic performance of Bovine Pericardium Organic Valvular Bioprosthesis (BVP). Methods: The BIOPRO Trial is an observational, retrospective, non-comparative, non-randomized, and multicenter study. We collected data from 903 patients with symptomatic, moderate, or severe valve disease who underwent BVP implants in the timeframe from 2013 to 2020 at three Brazilian institutions. Death, valve-related adverse events (AEs), functional recovery, and hemodynamic performance were evaluated at the hospital, at discharge, and six months and one year later. Primary analysis compared late (> 30 days after implant) linearized rates of valve-related AEs, such as thromboembolism, valve thrombosis, major hemorrhage, major paravalvular leak, and endocarditis, following objective performance criteria (OPC). Analysis was performed to include at least 400 valve-years for each valve position (aortic and mitral) for complete comparisons to OPC. Kaplan-Meier survival and major adverse cardiovascular and cerebrovascular event analyses were also performed. Results: This retrospective study analyzed follow-up data collected from 903 patients (834.2 late patient-years) who have undergone surgery for 455 isolated aortic valve replacement (50.4%), 382 isolated mitral valve replacement (42.3%), and 66 combined valve replacement or other intervention (7.3%). The linearized rates of valve-related AEs were < 2 × OPC. One-year survival rates were 95.1% and 92.7% for aortic and mitral valve replacement, respectively. This study demonstrated an improvement in the New York Heart Association classification from baseline and hemodynamic performance within an expected range. Conclusion: According to this analysis, BVP meets world standards for safety and clinical efficacy. [ABSTRACT FROM AUTHOR]

Leg prostheses specially adapted for cycling in patients with transtibial amputation can be advantageous for recreational practice; however, their required features are not fully understood. Therefore, we aimed to evaluate the efficiency of unilateral cycling with a transtibial prosthesis and the characteristics of different attachment positions (middle and tip of the foot) between the prosthetic foot and the pedal. The cycling practice was performed on an ergometer at 40 W and 60 W resistance levels while participants (n = 8) wore custom-made orthoses to simulate prosthesis conditions. Using surface electromyogram, motion tracking, and power meter pedals, biomechanical data were evaluated and compared with data obtained through regular cycling. The results showed that power delivery became more asymmetrical at lower workloads for both orthosis conditions, while hip flexion and muscle activity of the knee extensor muscles in the sound leg increased. While both pedal attachment positions showed altered hip and knee joint angles for the leg wearing the orthosis, the middle of the foot attachment presented more symmetric power delivery. In conclusion, the middle of the foot attachment position presented better symmetry between the intact and amputated limbs during cycling performed for rehabilitation or recreation. [ABSTRACT FROM AUTHOR]

Purpose: In up to a fifth of total knee replacements (TKR), surgeons are not capable of achieving good clinical and functional results. Despite comprehensive diagnostic workup, an underlying cause is not always identified in these patients. The purpose of this study is to compare native and prosthetic trochlear anatomies, to evaluate a potential source of morphologic mismatch and theoretically, of poor clinical outcomes. Methods: Native trochlear angles of 4116 knee CTs from 360 Knee Systems database of arthritic pre-operative TKR patients were evaluated. A semi-automated tridimensional analysis was performed to define the native trochlear angle in the coronal plane (NTA) among other 142 parameters. An active search was conducted to identify currently available TKR models; prosthetic trochlear orientation in the coronal plane (PTA) was extracted from the technical data provided by manufacturers. Results: The mean native trochlear angle (NTA) was 1.6° ± 6.6° (valgus) with a range from − 23.8° (varus) to 30.3°(valgus). A valgus NTA was present in 60.6% of the knees and 39.4% of them had a varus NTA. 89 TKR models were identified; trochlear details were available for 45 of them, of which 93% were designed with a valgus orientation of the prosthetic trochlear angle (PTA) and 6.9% showed a neutral (0°) PTA. Varus alignment of PTA was not present in any system. Angular numeric values for PTA were available for 34 models; these ranged from 0° to 15° of valgus, with a median value of 6.18° (SD ± 2.88°). Conclusion: This study shows a significant mismatch between native and prosthetic trochlear angles. A relevant proportion of the studied knees (41.45%) fall out of the trochlear angle range of currently available implants; representing a potential source for biomechanical imbalance. While further research is warranted to fully understand the clinical implications of the present study, manufacturers may need to take these findings into account for future implant designs. Level of evidence: Level III, retrospective cohort study. [ABSTRACT FROM AUTHOR]

Individuals with lower limb amputation have a high incidence of falls. Above-the-knee amputation and diabetes/vascular disease are both risk factors for falls. Microprocessor knee (MPK) technology may reduce falls in this population. The objective was to determine the association between MPKs and reduced injurious falls. A retrospective analysis of injurious falls within a large, national outcomes database was conducted. Inclusion was limited to adult K3 ambulators with unilateral, transfemoral, or knee disarticulation amputation due to diabetes/vascular disease. There were 744 out of 881 individuals that did not receive an MPK. Results showed that 16.3% of non-MPK users experienced an injurious fall compared to 7.3% of MPK users (p =.007). Not having an MPK resulted in significantly increased odds (unadjusted: OR: 2.47, 95% CI: 1.26–4.83, p =.009; adjusted for confounders: OR: 2.52, 95% CI: 1.28–4.94, p =.007) of incurring an injurious fall over a 6-month period. In conclusion, the current study found use of an MPK strongly associated with reduced injurious falls in a population of patients with amputation due to diabetes/vascular disease. The findings strongly support the use of MPK technology to mitigate fall risk, and in particular injurious falls requiring medical intervention. [ABSTRACT FROM AUTHOR]

Background: Elliptical shape humeral head prostheses have been recently proposed to reflect a more anatomic shoulder replacement. However, its effect on obligate glenohumeral translation during axial rotation compared to a standard spherical head is still not well understood. The purpose of the study was to compare obligate humeral translation during axial rotation using spherical and elliptical shaped humeral head prostheses. It was hypothesized that the spherical head design would show significantly more obligate translation when compared to the elliptical design. Methods: Six fresh-frozen cadaveric shoulders were utilized for biomechanical testing of internal (IR) and external (ER) rotation at various levels of abduction (0°, 30°, 45°, 60°) with lines of pull along each of the rotator cuff muscles. Each specimen underwent the following three conditions: (1) native; total shoulder arthroplasty (TSA) using (2) an elliptical and (3) spherical humeral head implant. Obligate translation during IR and ER was quantified using a 3-dimensional digitizer. The radius of curvature of the superoinferior and anteroposterior dimensions of the implants was calculated across each condition. Results: Posterior and inferior translation as well as compound motion of spherical and elliptical heads during ER was similar at all abduction angles (P > 0.05, respectively). Compared to the native humeral head, both implants demonstrated significantly decreased posterior translation at 45° (elliptical: P = 0.003; spherical: P = 0.004) and 60° of abduction (elliptical: P < 0.001; spherical: P < 0.001). During internal rotation at 0° abduction, the spherical head showed significantly more compound motion (P = 0.042) compared to the elliptical head. The spherical implant also demonstrated increased anterior translation and compound motion during internal rotation at 60° abduction (P < 0.001) compared to the resting state. This difference was not significant for the native or elliptical head design at this angle (P > 0.05). Conclusion: In the setting of TSA, elliptical and spherical head implants showed similar obligate translation and overall compound motion during axial rotation. A gained understanding of the consequences of implant head shape in TSA may guide future surgical implant choice for better recreation of native shoulder kinematics and potentially improved patient outcomes. Level of evidence: Controlled Laboratory Study. [ABSTRACT FROM AUTHOR]

Copyright of Magyar Traumatológia, Ortopédia, Kézsebészet, Plasztikai Sebészet is the property of Matrokplaszt Folyoirat Alapitvany and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Elliptical-shaped humeral head prostheses have recently been proposed to reflect a more anatomic shoulder replacement. However, its subsequent effect on micro-motion of the glenoid component is still not understood. Materials and methods: Six fresh-frozen, cadaveric shoulders (mean age: 62.7 ± 9.2 years) were used for the study. Each specimen underwent total shoulder arthroplasty using an anatomic stemless implant. At 15°, 30°, 45° and 60° of glenohumeral abduction, 50° of internal and external rotations in the axial plane were alternatingly applied to the humerus with both an elliptical and spherical humeral head design. Glenohumeral translation was assessed by means of a 3-dimensional digitizer. Micro-motion of the glenoid component was evaluated using four high-resolution differential variable reluctance transducer strain gauges, placed at the anterior, posterior, superior, and inferior aspect of the glenoid component. Results: The elliptical head design showed significantly more micro-motion in total and at the superior aspect of glenoid component during external rotation at 15° (total: P = 0.004; superior: P = 0.004) and 30° (total: P = 0.045; superior: P = 0.033) of abduction when compared to the spherical design. However, during internal rotation, elliptical and spherical heads showed similar amounts of micro-motion at the glenoid component at all tested abduction angles. When looking at glenohumeral translation, elliptical and spherical heads showed similar anteroposterior and superoinferior translation as well as compound motion during external rotation at all tested abduction angles. During internal rotation, the elliptical design resulted in significantly more anteroposterior translation and compound motion at all abduction angles when compared to the spherical design (P < 0.05). Conclusion: In the setting of total shoulder arthroplasty, the elliptical head design demonstrated greater glenohumeral translation and micro-motion at the glenoid component during axial rotation when compared to the spherical design, potentially increasing the risk for glenoid loosening in the long term. Level of evidence: Controlled Laboratory Study [ABSTRACT FROM AUTHOR]

Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Limb salvage reconstruction for pelvic tumors, especially periacetabular tumors, is challenging. We combined the use of dual mobility bearing and 3D-printed hemipelvic prosthesis to improve function and reduce the probability of complications after hemi-pelvic resection in patients with primary acetabular malignancy. The purpose of this study was to evaluate the efficacy and safety of this combination.Methods: Between October 2011 and May 2021, 11 patients with malignancies involving the acetabulum received hemipelvic replacement with a 3D-printed prosthesis and dual mobility bearing. Follow-up of postoperative survival, complications, and Musculoskeletal Tumor Society 93 (MSTS-93) lower limb functional scores were carried out. A finite element model of the postoperative pelvis was developed and input into the finite element analysis software. The Von Mises equivalent stress formula was used to analyze the stress distribution of each part of the pelvis under one gait cycle and the stress distribution at different angles of the hip joint.Results: By the last follow-up, 9 of the 11 patients (81.8%) were still alive, and 2 patients had local tumor recurrence. The complications including 1 deep infection and 1 dislocation of the artificial joint. Excluding 1 amputation patient, the average score of the remaining 8 patients at the last follow-up was 21.4/30 (71.3%) on the MSTS-93. In the reconstructed pelvis, stress distributions were concentrated on the junction between hemipelvic prosthesis and screw and iliac bone on the resected side, and between femoral prosthesis stem and femoral bulb, while the stress of polyethylene lining was small. Before impact, the polyethylene lining will rotate at a small angle, about 3°. The inner stress of polyethylene liner is greater than the outer stress in all conditions. The polyethylene liner has no tendency to slide out.Conclusion: Pelvic tumor resection and reconstruction using 3D-printed hemipelvic prosthesis combined with dual mobility bearing was an effective treatment for pelvic tumors. Our patients achieved good early postoperative efficacy and functional recovery. The dual mobility bearing is beneficial to prevent dislocation, and the mechanical distribution and wear of the prosthesis are acceptable. [ABSTRACT FROM AUTHOR]

Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Der Unfallchirurg is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Close communication between clinicians and dental technicians is an important factor in providing successful prostheses. The exchange of opinions with laboratories has mainly been in the form of written prescriptions and a photos, but it has been reported that information transmission may be limited. Currently, as digital technology-based prosthesis fabrication is common, 3D image objects can be stored on the web and can be easily viewed through a mobile web browser. In this article, we introduce cases where the design of the prosthesis was improved by designing the prosthesis using CAD software and reviewing the prosthesis designed with the clinical side through a web viewer. Through this protocol, it was possible to improve the occlusal surface and crown contour, the opposing teeth condition, the size of the gingival embrasure, and the shape of pontic. The process of sharing, discussing, and modifying the prosthesis design with the clinician and technician through a web viewer contributes to reflecting the diversity of oral conditions and individualized needs, thereby helping to make functional and esthetic prostheses. [ABSTRACT FROM AUTHOR]

Objectives: To systematically assess the literature and report on (1) the frequency of occurrence of buccal soft tissue dehiscence (BSTD) at implants, (2) factors associated with the occurrence of BSTD and (3) treatment outcomes of reconstructive therapy for the coverage of BSTD. Materials and Methods: Two systematic reviews addressing focused questions related to implant BSTD occurrence, associated factors and the treatment outcomes of BSTD coverage served as the basis for group discussions and the consensus statements. The main findings of the systematic reviews, consensus statements and implications for clinical practice and for future research were formulated within group 3 and were further discussed and reached final approval within the plenary session. Results: Buccally positioned implants were the factor most strongly associated with the risk of occurrence of BSTD, followed by thin tissue phenotype. At immediate implants, it was identified that the use of a connective tissue graft (CTG) may act as a protective factor for BSTD. Coverage of BSTD may be achieved with a combination of a coronally advanced flap (CAF) and a connective tissue graft, with or without prosthesis modification/removal, although feasibility of the procedure depends upon multiple local and patient‐related factors. Soft tissue substitutes showed limited BSTD coverage. Conclusion: Correct three‐dimensional (3D) positioning of the implant is of utmost relevance to prevent the occurrence of BSTD. If present, BSTD may be covered by CAF +CTG, however the evidence comes from a low number of observational studies. Therefore, future research is needed for the development of further evidence‐based clinical recommendations. [ABSTRACT FROM AUTHOR]

Objectives: To systematically assess the literature and report on (1) the frequency of occurrence of buccal soft tissue dehiscence (BSTD) at implants, (2) factors associated with the occurrence of BSTD and (3) treatment outcomes of reconstructive therapy for the coverage of BSTD. Materials and Methods: Two systematic reviews addressing focused questions related to implant BSTD occurrence, associated factors and the treatment outcomes of BSTD coverage served as the basis for group discussions and the consensus statements. The main findings of the systematic reviews, consensus statements and implications for clinical practice and for future research were formulated within group 3 and were further discussed and reached final approval within the plenary session. Results: Buccally positioned implants were the factor most strongly associated with the risk of occurrence of BSTD, followed by thin tissue phenotype. At immediate implants, it was identified that the use of a connective tissue graft (CTG) may act as a protective factor for BSTD. Coverage of BSTD may be achieved with a combination of a coronally advanced flap (CAF) and a connective tissue graft, with or without prosthesis modification/removal, although feasibility of the procedure depends upon multiple local and patient‐related factors. Soft tissue substitutes showed limited BSTD coverage. Conclusion: Correct three‐dimensional (3D) positioning of the implant is of utmost relevance to prevent the occurrence of BSTD. If present, BSTD may be covered by CAF +CTG, however the evidence comes from a low number of observational studies. Therefore, future research is needed for the development of further evidence‐based clinical recommendations. [ABSTRACT FROM AUTHOR]

Objectives: To compare 2 implant scan bodies with different geometry on the accuracy of the virtual alignment process in the digital workflow. Materials and Methods: A master model of the edentulous maxilla with 6 implants and multiunit abutments (MUA) inserted was fabricated. Six dome‐shaped and cuboidal scan bodies were mounted on the MUAs, respectively, and consecutively scanned by a laboratory scanner 10 times. The original scans were imported to a dental‐specific CAD software and virtually aligned with the default CAD model in the implant library. Thus, 10 aligned models were created. Both the original scans and the aligned models were evaluated by an inspection software for deviation of the scan body surfaces, the centroids of scan body and MUA, the scan body center‐axis, and the inter‐MUA distances/angles. The two‐sample T‐test/Mann–Whitney U test were used to analyze the data with the level of significance set at 0.05. Results: The cuboidal group showed significant greater deviations of the model surface (13.9 µm vs. 10.7 µm) and the MUA centroids (31.7 µm vs. 22.8 µm) but smaller deviation of the inter‐MUA angle (0.047° vs. 0.070°) than those of the dome‐shaped group (p <.05). No significant differences in the deviation of scan body centroids, center‐axis, and the inter‐MUA distances between the 2 groups were found. Conclusions: Virtual alignment of implant scan body affected the accuracy of the digital workflow for complete‐arch implant‐supported prostheses (up to ~30 µm/0.09°). Different geometries of the implant scan body could also influence the transfer accuracy in the CAD process. [ABSTRACT FROM AUTHOR]

Purpose: Error testing at each stage of prosthetic manufacturing remains relatively underdeveloped for computer‐aided design/computer‐aided manufacturing methods, and no experimental studies have validated the computer‐aided design programs. This study aimed to test the accuracy and trueness of the computer‐aided design of a three‐unit fixed prosthesis. Materials and Methods: Three computer‐aided design programs (Exocad, Dental System™, and inLab 16) were tested on the designs of a three‐unit fixed partial denture, and a three‐dimensional analysis program was used to calculate the internal clearance error for the computer‐aided design prostheses. The Kruskal–Wallis and Dunn's post hoc tests were used to reveal significant differences in trueness between the three computer‐aided design programs (α < 0.05). Results: Dental System™ showed the lowest mean error values for #24 and #26 at the mesial margin (both 0 µm), mesial wall (0.10, 0.12 µm, respectively), occlusal surface (–0.05, 0.10 µm), distal wall (0.23, –0.02 µm), and distal margin (both 0 µm). In sum, except for the mesial margin and distal margin site of tooth #26, the mean error value of Dental System™ was statistically the lowest, followed by those of Exocad and inLab 16 (p < 0.003). Conclusions: The accuracy of computer‐aided design differed according to the type of computer‐aided design program. Dental System™ achieved the best trueness at the margins, axial walls, and occlusal surface, followed by Exocad and inLab 16. [ABSTRACT FROM AUTHOR]

Purpose: Despite numerous well-conducted studies and meta-analyses, the management of the patella during total knee arthroplasty (TKA) remains controversial. The aim of our study was to compare the clinical and radiological outcomes between patients with and without patellar resurfacing and to determine the influence of resurfacing on patellar tracking with a "patella-friendly" prosthesis. Methods: A single-centered prospective randomized controlled study was performed between April 2017 and November 2018. Two hundred and forty-five consecutive patients (250 knees) scheduled for TKA were randomized for patellar resurfacing or patella non-resurfacing. All patients received the same total knee prosthesis and were evaluated clinically and radiologically, including the International Knee Society Score (KSS knee and function), Forgotten Joint Score (FJS), anterior knee pain (AKP), pain when climbing stairs, patellar tilt, and patellar translation. Results: Two hundred and twenty-nine knees were available for clinical evaluation and 221 knees for radiographic analysis. The revision rate for patellofemoral cause was 3.1% (7 cases) with no difference between the groups (p = 0.217). There was no difference in survival rate between patellar resurfacing (88.3%) and non-resurfacing (85.3%) after 24 months (p = 0.599). There were no differences in KSS functional component (p = 0.599), KSS knee component (p = 0.396), FJS (p = 0.798), and AKP (p = 0.688) at a mean follow-up of 18 months. There was twice as much stair pain for the non-resurfacing group (17.1% versus 8.5%) (p = 0.043). There was patellar tilt in 43% of resurfaced knees (n = 50/116) versus 29% in non-resurfaced knees (n = 30/105) (p = 0.025); however, there was more patellar translation in the non-resurfaced group (21.0% versus 7.8%) (p < 0.001). There were no specific complications attributed to the patellar resurfacing procedure. There were four secondary patellar resurfacing procedures (3.6%) in the non-resurfaced group after a mean of 10 ± 7 months (1–17) postoperatively. Conclusion: There is no superiority of patellar resurfacing or non-resurfacing in terms of clinical or radiological outcomes at mid-term. Secondary patellar resurfacing is rare. There is not enough evidence to recommend systematic patellar resurfacing with a "patella-friendly" prosthesis. Level of evidence: 1. [ABSTRACT FROM AUTHOR]

Introduction: Elliptical shape humeral head prostheses have been proposed to reflect a more anatomic shoulder replacement. Its effect on the rotational range of motion (ROM) compared to a standard spherical head is still not understood. The purpose was to investigate if there would be a difference in rotational ROM when comparing elliptical and spherical prosthetic heads in a dynamic shoulder model. The authors hypothesized that the use of elliptical heads would result in significantly more rotational ROM compared to the spherical head design. Materials and methods: Six fresh-frozen, cadaveric shoulders were evaluated using a dynamic shoulder model. After being tested in the native condition, each specimen underwent 6 conditions in the hemiarthroplasty state: (1) matched-fit spherical head, (2) oversized spherical head, (3) undersized spherical head, (4) matched-fit elliptical head, (5) oversized elliptical head, and (6) undersized elliptical head. Following conversion to total shoulder arthroplasty (TSA), the 6 prior conditions were rerun. Each condition was tested at 0°, 30° and 60° of glenohumeral abduction. Rotational ROM was quantified using 3-dimensional tracking, while dynamically applying alternating forces for internal and external rotation via the rotator cuff tendons. Results: Elliptical and spherical prosthetic heads showed no significant difference in the degree of the total, internal, and external rotational ROM for both the hemiarthroplasty and TSA state. Conversion from hemiarthroplasty to TSA resulted in less degree of total rotational ROM for both head designs in all abduction positions, without reaching statistical significance. There was a significant decrease in total, internal, and external rotational ROM for both elliptical and spherical heads in every replacement condition, when comparing 0° to 30° and 60° of abduction (P < 0.05, respectively). Conclusion: In a dynamic shoulder model, elliptical and spherical prosthetic head designs showed no significant difference in the degree of the total, internal, and external rotational ROM in both the hemiarthroplasty and TSA state. Level of evidence: Controlled laboratory study [ABSTRACT FROM AUTHOR]

The Inspiris Resilia tissue valve was recently introduced into clinical practice. This review summarizes the pre-clinical and clinical studies leading to this new bioprosthesis. The novel Resilia tissue was tested extensively in a large animal model. The clinical use of the tissue started in 2011 with the European Feasibility study, followed by a North-American multi-center study. Since 2017, the Inspiris Resilia valve has been in full commercial use. Further prospective evaluations and registries are ongoing. The Inspiris Resilia valve was clinically introduced after pre-clinical tests revealed superiority compared to contemporary therapy such as the Perimount valve. Prospective long-term follow-up studies on Resilia are ongoing since 2011 and reveal no major complications. Full 5-year data show no signs of early degeneration, but longer follow-up is certainly still needed. Several prospective registries are actively monitoring the outcome with the Inspiris Resilia valve now. The novel tissue, designed to mitigate calcification and increase durability, together with the expandable stent, facilitating potential future valve-in-valve (ViV) procedures, are the cutting-edge aspects. Clinical use in younger patients is currently ongoing: their follow-up and outcome will determine the added value of this valve. [ABSTRACT FROM AUTHOR]

This research presents the design and preliminary evaluation of an electromyographically (EMG) controlled 2-degree-of-freedom (DOF) ankle-foot prosthesis designed to enhance rock climbing ability in persons with transtibial amputation. The prosthesis comprises motorized ankle and subtalar joints, and is capable of emulating some key biomechanical behaviors exhibited by the ankle-foot complex during rock climbing maneuvers. The free space motion of the device is volitionally controlled via input from EMG surface electrodes embedded in a custom silicone liner worn on the residual limb. The device range of motion is 0.29 radians of each dorsiflexion and plantar flexion, and 0.39 radians each of inversion and eversion. Preliminary evaluation of the device was conducted, validating the system mass of 1292 grams, build height of 250 mm, joint velocity of 2.18 radians/second, settling time of 120 milliseconds, and steady state error of 0.008 radians. Clinical evaluation of the device was performed during a preliminary study with one subject with transtibial amputation. Joint angles of the ankle-foot, knee, and hip were measured during rock climbing with the robotic prosthesis and with a traditional passive prosthesis. We found that the robotic prosthesis increases the range of achieved ankle and subtalar positions compared to a standard passive prosthesis. In addition, maximum knee flexion and hip flexion angles are decreased while climbing with the robotic prosthesis. These results suggest that a lightweight, actuated, 2-DOF EMG-controlled robotic ankle-foot prosthesis can improve ankle and subtalar range of motion and climbing biomechanical function. [ABSTRACT FROM AUTHOR]

Copyright of Obere Extremitat is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the prevalence of rheumatic heart disease in the developing world, mechanical heart valves in the younger patient population remain the prostheses of choice if repair is not feasible. Despite their durability, mechanical valves are burdened by coagulation and thromboembolism. Modern design tools can be utilized during the design process of mechanical valves, which allow a more systematic design approach and more detailed analysis of the blood flow through and around valves. These tools include computer-aided design, manufacturing, and engineering, such as computational fluid dynamics and finite element analysis, modern manufacturing techniques such as additive manufacturing, and sophisticated in-vitro and in-vivo tests. Following this systematic approach, a poppet valve was redesigned and the results demonstrate the benefits of the method. More organized flow patterns and fewer complex fluid structures were observed. The alternative trileaflet valve design has also been identified as a potential solution and, if a similar design approach is adopted, it could lead to the development of an improved mechanical heart valve in the future. It is imperative that researchers in developing countries continue their search for a mechanical heart valve with a reduced thromboembolic risk, requiring less or no anticoagulation. [ABSTRACT FROM AUTHOR]

Featured Application: A potential application of this work is an ergonomic method for designing personalized hiking and jogging prostheses for use in rehabilitation after amputation. This work addresses the design, analysis, and validation of a transtibial custom prosthesis. The methodology consists of the usage of videometry to analyze angular relationships between joints, moments, and reaction forces in the human gait cycle. The customized geometric model of the proposed prosthesis was defined by considering healthy feet for the initial design. The prosthesis model was developed by considering the Flex-Foot® Variflex® architecture on a design basis. By means of the analytical method, the size and material of the final model were calculated. The behavior of the prosthesis was evaluated analytically by a curved elements analysis and the Castigliano theorem, and numerically by the Finite Element Method (FEM). The outcome shows the differences between the analytical and numerical methods for the final prosthesis design, with an error rate no greater than 6.5%. [ABSTRACT FROM AUTHOR]

Background: Biliary decompression can reduce symptoms and improve quality of life in patients with malignant biliary obstruction. Endoscopically placed stents have become the standard of care for biliary drainage with the aim of improving hepatic function, relieving jaundice, and reducing adverse effects of obstruction. The purpose of this study was to evaluate the performance characteristics of a newly-designed, uncovered metal biliary stent for the palliation of malignant biliary obstruction.Methods: This post-market, prospective study included patients with biliary obstruction due to a malignant neoplasm treated with a single-type, commercially available uncovered self-expanding metal stent (SEMS). Stents were placed as clinically indicated for palliation of jaundice and to potentially facilitate neo-adjuvant chemotherapy. The main outcome measure was freedom from recurrent biliary obstruction (within the stent) requiring re-intervention within 1, 3, and 6 months of stent insertion. Secondary outcome measures included device-related adverse events and technical success of stent deployment.Results: SEMS were placed in 113 patients (73 men; mean age, 69); a single stent was inserted in 106 patients, and 2 stents were placed in 7 patients. Forty-eight patients survived and/or completed the 6 month study protocol. Freedom from symptomatic recurrent biliary obstruction requiring re-intervention was achieved in 108 of 113 patients (95.6, 95%CI = 90.0-98.6%) at study exit for each patient. Per interval analysis yielded the absence of recurrent biliary obstruction in 99.0% of patients at 1 month (n = 99; 95%CI = 97.0-100%), 96.6% of patients at 3 months (n = 77; 95%CI = 92.7-100%), and 93.3% of patients at 6 months (n = 48; 95%CI = 86.8-99.9%). In total, only 5 patients (4.4%) were considered failures of the primary endpoint. Most of these failures (4/5) were due to stent occlusion from tumor ingrowth or overgrowth. Overall technical success rate of stent deployment was 99.2%. There were 2 cases of stent-related adverse events (1.8%). There were no cases of post-procedure stent migration, stent-related perforation, or stent-related deaths.Conclusions: This newly designed and marketed biliary SEMS system appears to be effective at relieving biliary obstruction and preventing re-intervention within 6 months of insertion in the overwhelming majority of patients. The device has an excellent safety profile, and associated high technical success rate during deployment.Trial Registration: The study was registered on clinicaltrials.gov on 14 October 2013 and the study registration number is NCT01962168. University of Massachusetts Medical School did not participate in the study. [ABSTRACT FROM AUTHOR]

Background: The incidence of patient dissatisfaction due to anterior knee pain (AKP) and patellar crepitus after total knee arthroplasty (TKA) remains a concern. However, it has been shown that improvements in the femoral component of traditional prostheses could reduce these instances of pain in the case of TKA performed with patellar resurfacing. This study aims to investigate whether TKA without patellar resurfacing can also benefit from the aforementioned femoral component modification in reducing AKP and patellar crepitus post-TKA.Methods: Sixty-two patients (85 knees) who underwent TKA using the modern prosthesis and 62 age- and sex-matched patients (90 knees) fitted with the traditional prosthesis were enrolled in this study. The occurrence of AKP and patellar crepitus as well as the Knee Society Score (KSS) were consequently recorded, and the data was analyzed in order to determine whether there was a statistically significant difference between the two groups.Results: The incidence of AKP was significantly lower in the study group compared with the control group at the 3-month and 1-year follow-ups (4.7% vs. 13.3% [p = 0.048] and 3.5% vs. 13.3% [p = 0.021], respectively). In addition, the incidence of patellar crepitus was also significantly lower in the study group compared with the control group at the 3-month and 1-year follow-ups (15.3% vs. 34.4% [p = 0.004] and 10.6% vs. 28.9% [p = 0.002], respectively). There was no significant difference in the KSS between the two groups.Conclusions: These results revealed that TKA without patellar resurfacing will indeed benefit from the modified femoral implant design in reducing AKP and patellar crepitus, a finding that may be beneficial to surgeons who select implants for their patients when patellar resurfacing is not planned or not possible due to other reasons. [ABSTRACT FROM AUTHOR]

Copyright of Türkiye Klinikleri Kozmetik Dermatoloji Özel Dergisi is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shanghai Jiaotong University (Medical Science) is the property of Journal of Shanghai Jiaotong University (Medical Science) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Total hip arthroplasty (THA) is a very successful procedure in orthopedics. Still polyethylene wear and gait deficits are limiting the clinical success. It is important to reconstruct leg length (LL) and femoral offset (FO) anatomically in order to have the best possible result of a THA. Gait deficits can arise due to leg length discrepancy as well as changes in the abductor moment arm. In THA, LL and FO are strongly determined by the orientation, size and geometry of the femoral stem. Methods: This radio-anatomical study used the data of a prospective cases series of 112 patients who underwent 126 primary THAs and had completed a 1-year follow-up examination. FO and LL were compared between the conventional straight stem in vivo and a computed simulated implantation of a short curved stem, using the preand postoperative pelvic radiographs of the same patients. Results: In this simulation of the short curved stem statistically significantly restored native FO (p=0.010) and LL (p=0.000) better, compared to the conventional straight stem. Conclusions: Thus, the short curved stem restores FO and LL better, and could potentially prevent gait deficits. [ABSTRACT FROM AUTHOR]

Three‐dimensional (3D) printing is a digital rapid prototyping technology based on a discrete and heap‐forming principle. We identified 53 articles from PubMed by searching "Hip" and "Printing, Three‐Dimensional"; 52 of the articles were published from 2015 onwards and were, therefore, initially considered and discussed. Clinical application of the 3D printing technique in the hip joint mainly includes three aspects: a 3D‐printed bony 1:1 scale model, a custom prosthesis, and patient‐specific instruments (PSI). Compared with 2‐dimensional image, the shape of bone can be obtained more directly from a 1:1 scale model, which may be beneficial for preoperative evaluation and surgical planning. Custom prostheses can be devised on the basis of radiological images, to not only eliminate the fissure between the prosthesis and the patient's bone but also potentially resulting in the 3D‐printed prosthesis functioning better. As an alternative support to intraoperative computer navigation, PSI can anchor to a specially appointed position on the patient's bone to make accurate bone cuts during surgery following a precise design preoperatively. The 3D printing technique could improve the surgeon's efficiency in the operating room, shorten operative times, and reduce exposure to radiation. Well known for its customization, 3D printing technology presents new potential for treating complex hip joint disease. [ABSTRACT FROM AUTHOR]

Purpose: Decades of innovations in total knee arthroplasty (TKA) design have led to large number of possible prosthesis combinations in regards fixation, posterior stability, bearing mobility, bearing surface, and patella resurfacing, each of which can alter the revision risk. The accumulative effect when the lowest risk combination in each design category, or "Optimum Prosthesis Combination" (OPC) is utilized remains unknown. The purpose of this analysis was to first, identify the OPC and second, to compare the revision risk of a cohort who received the OPC to a cohort who received an Alternative Prosthesis Combination (APC).Methods: National registry revision risk data for primary TKA for osteoarthritis were obtained from September 1999 to December 2015 for two patient cohorts, those receiving an OPC and those receiving an APC. OPC was defined as TKA with the lowest revision risk option for five primary TKA design categories; fixation, posterior stability, bearing mobility, bearing surface, and patella resurfacing, while APC had one or more higher risk options.Results: Of the 482,373 included TKA, 42,008 (8.7%) were in the OPC cohort, who received a minimally stabilized, fixed bearing TKA with cross-linked polyethylene with patella resurfacing. Both cohorts had similar demographics. At 10 years, the OPC cohort had a Cumulative Percent Revision of 2.4% (95% CI 2.1, 2.8) compared to 5.5% (95% CI 5.4, 5.6) for the APC cohort. For all patients, revision risk of the APC cohort was higher at all times [151% greater at ≥ 3 years (p < 0.001)]. Loosening/lysis was the most common cause of revision in the ACP cohort (1.1%), while it was the second most common cause in the OPC cohort (0.3%). The increased risk was apparent in all age and gender subgroups, with the highest risk increase seen in males ≥ 65 years.Conclusions: Patients receiving the lowest risk prosthesis design combination or Optimum Prosthesis Combination TKA had a 60% lower revision risk, with similar demographics to the Alternative Prosthesis Combination TKA.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Many failures in total joint replacement are associated to prosthesis‐to‐bone mismatch. With recent additive‐manufacturing, that is, 3D‐printing, custom‐made prosthesis can be created by laser‐melting metal powders layer‐by‐layer. Ankle replacement is particularly suitable for this progress because of the limited number of sizes and the poor bone stock. In this study a novel procedure is presented for subject‐specific ankle replacements, including medical‐imaging, joint modelling, prosthesis design, and 3D‐printing. Three shank‐foot specimens were CT‐scanned, and corresponding 3D bone models of the tibia, fibula, talus, and calcaneus were obtained. From these models, specimen‐specific implant sets were designed according to three different concepts, and 3D‐printed from cobalt‐chromium‐molybdenum powder. Accuracy of the overall procedure was assessed via distance map comparisons between original anatomical and final metal implants. Restoration of natural ankle joint mechanics was check after implantation of each of the three sets. In a special rig, a manually‐driven dorsi/plantar‐flexion was applied throughout the passive arc. Additionally, at three different joint positions, joint torques were imposed in the frontal and axial anatomical planes. Mean manufacturing errors were found to be smaller than 0.08 mm. Consistent motion patterns were observed over repetitions, with the mean standard deviation smaller than 1.0 degree. In each ankle specimen, mobility, and stability at the replaced joints compared well with the original natural condition. For the first time, custom‐made implants for total ankle replacements were designed, manufactured with additive technology and tested. This procedure is a first fundamental step toward the development of completely personalized prostheses. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [ABSTRACT FROM AUTHOR]

Copyright of Magyar Traumatológia, Ortopédia, Kézsebészet, Plasztikai Sebészet is the property of Matrokplaszt Folyoirat Alapitvany and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Osteopenia of the front half of the distal femur is a well-known problem after total knee arthroplasty (TKA) with secondary issues after years, especially when must be addressed fractures or revisions for loosening. Stress shielding has been recognized as a cause in different biomechanical studies of the bone.Question/purposes: It was logical to look for a solution by changing the design to minimize stress shielding behind the femoral shield.Patients and methods: It was proved that radiological measure of bone density was reliable although not so early and accurate as densitometry. We used a shield without posterior fixation of the trochlea in a series of 21 TKA with radiological measures, preoperative, at 3 months and at 5 years. We compared the results with those of a series of classical TKA in the same category of age and sex.Results: The TKA without trochlea posterior fixation presented a significantly reduced osteopenia compared to the classical design of the femoral shield.Conclusion: It seems that the non-fixation of the posterior surface of the trochlea may reduce osteopenia in TKA and so the risk of fractures and complications when revision surgery.Level of evidence: 2a. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Herz-, Thorax- und Gefaesschirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This report presents a method for determining the optimum arrangement of implants and the optimum scheme of prosthesis splinting using biomechanics and three-dimensional finite element analysis. The three-dimensional finite element structural analysis method was used to determine the distribution of occlusal forces on teeth and dental implants. The results of the analysis showed that force distribution on occlusal surfaces does not change significantly with changes in the scheme of prosthesis splinting or implant positions. The induced stresses in bone are sensitive to the scheme of prosthesis splinting and implant positions. Induced stresses on implants for different schemes of prosthesis splinting and different implant positions varied as much as 1,000%. Therefore, the selection of implant positions and of the scheme of prosthesis splinting is critical for the longevity and stability of an implant prosthesis. [ABSTRACT FROM AUTHOR]

The position of osseointegrated implants in the edentulous maxilla is dictated by available bone and can vary widely among patients. Anatomy limits the amount of bone available for placement of osseointegrated implants. With increasing resorption, the number, length, and position of implants are further compromised. Bone grafts are frequently needed to place implants of adequate length. The variability of implant placement indicates the need for multiple prosthesis designs in the maxilla. Prosthesis design considerations are suggested for patients with minimal, moderate, and severe resorption of the edentulous maxilla. [ABSTRACT FROM AUTHOR]

Maxillary prosthetic restorations on osseointegrated implants are often problematic because of implant location, orientation, and need for lip support. A new design for a hybrid maxillary prosthesis that will provide good esthetics and phonetics, as well as ensure optimum conditions for oral hygiene and patient comfort, is proposed. The design includes separate support, lateral stabilization, and retention. Support is derived from elevated areas at the midline and on the extensions of a bar screwed to dental implants ad modum Brånemark. Lateral stabilization is obtained by a removable framework closely fitting the bar. Four precision attachments provide adjustable retention without influencing support. Technical aspects of the procedure are described. [ABSTRACT FROM AUTHOR]

Purpose This paper aims to review the latest applications in terms of three-dimensional printed (3DP) metal implants in orthopedics, and, importantly, the design of 3DP metal implants through a series of cases operated at The Second Hospital of Jilin University were presented.Design/methodology/approach This paper is available to practitioners who are use 3DP implants in orthopedics. This review began with the deficiency of traditional prostheses and basic concepts of 3DP implants. Then, representative 3DP clinical cases were summarized and compared, and the experiences using customized prostheses and directions for future potential development are also shown.Findings The results obtained from the follow-up of clinical applications of 3DP implants show that the 3D designed and printed metal implants could exhibit good bone defect matching, quick and safe joint functional rehabilitation as well as saving time in surgery, which achieved high patient satisfaction collectively.Originality/value Single center experiences of 3DP metal implants design were shared and the detailed technical points between various regions were compared and analyzed. In conclusion, the 3DP technology is infusive and will present huge potential to reform future orthopedic practice. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction We performed a single-center nonrandomized study on patients who underwent endovascular aneurysm repair using polymer-filled or other self-expanding endografts. Methods Consecutive patients with asymptomatic infrarenal abdominal aortic aneurysms who underwent endovascular repair were retrospectively reviewed. They were divided into a polymer-filled (n = 20) or self-expanding group (n = 42). Baseline characteristics, operative mortality and morbidity, and follow-up data were compared. Results Aneurysm diameter, neck and iliac morphologies did not differ between the two groups. Technical success was 100%. The 30-day mortality was 0% and 2.4% in the polymer-filled and self-expanding group, respectively. At a mean follow-up of 17 months, the changes in sac size were −2.1 mm and −5.1 mm (p = 0.144) at one year, and −3.5 mm and −7.7 mm (p = 0.287) at 2 years in the polymer-filled and self-expanding group, respectively. The polymer-filled group had 7 (35%) type II endoleaks, and the self-expanding group had 1 (2.4%) type Ia and 13 (31%) type II endoleaks. Neck diameter remained stable in the polymer-filled stent-grafts whereas there was progressive neck degeneration in the self-expanding group. The rates of reintervention and overall survival were similar in both groups. The presence of an endoleak was the only predictor of non-regression of the aneurysm (odds ratio = 17.00, 95% confidence interval: 4.46–64.88, p < 0.001). Conclusion Polymer-filled endografts had similar safety, effectiveness, and durability to other self-expanding endografts. The major advantage is the small iliofemoral access. They also have the potential long-term benefit of a more stable neck. [ABSTRACT FROM AUTHOR]

During the last decade, due to the digitalization of many procedures in the dental workflow, dentistry has undergone many changes. To begin with, virtual articulators substituted traditional mechanical articulators. Thanks to virtual articulators, exploring more options (manufacture in clinic, laboratory in different materials, among others) for each case became possible. Now, this study proposes a step forward in the registration of the patients’ mandibular movements, which allows taking into account the kinematics of each patient’s mandible in the design of prostheses. Surgeons and dentists require a comprehensive simulation system of the mandibular movements as a support for their design work. Taking into consideration the market needs, this article describes the work carried out to develop a method to capture mandibular movement. Using a Leap Motion device and rapid prototyped pieces, the developed system is simple and economically affordable. To design a dental prosthesis taking into account the movements of the antagonist, the most significant information regarding these mandibular movements—lateral movements, retrusion, protrusion and chewing—is necessary. In order to minimize interventions at the clinic, this kinematic design is essential because it eliminates occlusal interferences. However, this registration system is only applicable when an intraoral scanner and a virtual face bow are already integrated. Since the maxillary and mandibular casts must simulate the registered movements, the origin and relative position between both casts is essential. This virtual location of models and simulation of these movements enables the dentist, surgeon and lab technician to achieve a more interactive design, thus leading to a more functional design. [ABSTRACT FROM AUTHOR]

People with transtibial amputation often experience skin breakdown due to the pressures and shear stresses that occur at the limb-socket interface. The purpose of this research was to create a transtibial finite element model (FEM) of a contemporary prosthesis that included complete socket geometry, two frictional interactions (limb-liner and liner-socket), and an elastomeric liner. Magnetic resonance imaging scans from three people with characteristic transtibial limb shapes (i.e., short-conical, long-conical, and cylindrical) were acquired and used to develop the models. Each model was evaluated with two loading profiles to identify locations of focused stresses during stance phase. The models identified five locations on the participants' residual limbs where peak stresses matched locations of mechanically induced skin issues they experienced in the 9 months prior to being scanned. The peak contact pressure across all simulations was 98 kPa and the maximum resultant shear stress was 50 kPa, showing reasonable agreement with interface stress measurements reported in the literature. Future research could take advantage of the developed FEM to assess the influence of changes in limb volume or liner material properties on interface stress distributions. Graphical abstract Residual limb finite element model. Left: model components. Right: interface pressures during stance phase. [ABSTRACT FROM AUTHOR]

Management of right ventricular outflow tract obstruction has undergone much change over the last century. Techniques described in the literature include anatomical repairs and the use of various patches, conduits, and innovative grafts. However, many of these approaches require reoperations or catheter-based interventions, leading to increased morbidity, mortality, and cost. The search for the ideal long-lasting conduit continues and there are new techniques on the horizon, using genetic engineering and nanotechnology. This review discusses the evolution of various techniques for repair of right ventricular outflow tract obstruction, past and current conduits, as well as ongoing research. [ABSTRACT FROM AUTHOR]

Background and Aim: A recent survey of people with lower limb absence revealed that patients' satisfaction with their foam cosmesis is lower than desired. The aim of this project was to improve the lifelike appearance, functionality and durability of the cosmesis through a user-centred design methodology.Technique: Concept development and prototyping led to a new cosmesis design which features a cut-out located at the knee, inserted with an artificial patella made of a more rigid foam. It also features a full-length zip which provides easy access for maintenance. The new cosmesis was then mechanically tested for over 1 million cycles and clinically tested by six transfemoral prosthesis users over 18 patient months.Discussion: The new design is significantly more durable than the current standard model and has an enhanced lifelike appearance. It has potential to improve users' body image and reduce costs for healthcare providers. Clinical relevance This study contributes to practice by offering a new cosmesis design with enhanced appearance and durability, with the potential to improve patients' body image and reduce costs associated with cosmesis fitting and maintenance. [ABSTRACT FROM AUTHOR]

Background: Prosthetic arm research predominantly focuses on "bionic" but not body-powered arms. However, any research orientation along user needs requires sufficiently precise workplace specifications and sufficiently hard testing. Forensic medicine is a demanding environment, also physically, also for non-disabled people, on several dimensions (e.g., distances, weights, size, temperature, time).Methods: As unilateral below elbow amputee user, the first author is in a unique position to provide direct comparison of a "bionic" myoelectric iLimb Revolution (Touch Bionics) and a customized body-powered arm which contains a number of new developments initiated or developed by the user: (1) quick lock steel wrist unit; (2) cable mount modification; (3) cast shape modeled shoulder anchor; (4) suspension with a soft double layer liner (Ohio Willowwood) and tube gauze (Molnlycke) combination. The iLimb is mounted on an epoxy socket; a lanyard fixed liner (Ohio Willowwood) contains magnetic electrodes (Liberating Technologies). An on the job usage of five years was supplemented with dedicated and focused intensive two-week use tests at work for both systems.Results: The side-by-side comparison showed that the customized body-powered arm provides reliable, comfortable, effective, powerful as well as subtle service with minimal maintenance; most notably, grip reliability, grip force regulation, grip performance, center of balance, component wear down, sweat/temperature independence and skin state are good whereas the iLimb system exhibited a number of relevant serious constraints.Conclusions: Research and development of functional prostheses may want to focus on body-powered technology as it already performs on manually demanding and heavy jobs whereas eliminating myoelectric technology's constraints seems out of reach. Relevant testing could be developed to help expediting this. This is relevant as Swiss disability insurance specifically supports prostheses that enable actual work integration. Myoelectric and cosmetic arm improvement may benefit from a less forgiving focus on perfecting anthropomorphic appearance. [ABSTRACT FROM AUTHOR]