Wire Insertion Research Articles

Finite element analyses of lateral condyle fracture fixation in paediatrics regarding configuration of Kirschner-wire

BackgroundThis study aimed to discover the most stable outcome among different Kirschner-wire (K-wire) configurations for fixation of a lateral condyle fracture (Milch type II) in different loads of stress by using finite element analyses (FEA).MethodsThe right humerus of a 6-year-old boy with a lateral condyle fracture (Milch type II), was modelled with a computer aided engineering. Using FEA, peak von Mises stress and stiffness were evaluated first for a single K-wire fixation by varying the angle (0, 5, 10, 15, 20, 25, 30 degrees). Then, based on the single K-wire result, assessment of peak von Mises stress and stiffness were evaluated via FEA for two- or three-wire fixation under various configurations (two convergent, two parallel, three divergent).ResultsSingle K-wire fixation by 5 and 25 degrees had the lowest peak von Mises stress. The fracture site showed higher stiffness at 0, 5 and 15 degrees. Considering the collected results and clinical situation, 5 degree K-wire was selected for the FEA of multiple K-wire fixation. For multiple K-wire fixation, three divergent (5–20-35 degrees) K-wires showed better stability, both in peak von Mises stress and stiffness, than any two-K-wire configurations. Among two K-wire fixations, two divergent (5–50 degrees) K-wires provided the lowest von Mises stress in varus and valgus while two divergent (5–65 degrees) K-wires showed better results in flexion, extension, internal and external rotation, and both configurations showed similar results in stiffness.ConclusionsWe successfully created a paediatric lateral condyle fracture (Milch type II) model which was used to conduct FEA on different K-wire configurations to achieve stability of the fracture. Our results show that an initial K-wire inserted at 5 degrees, followed by the insertion of a second divergent wire at either 45 or 60 degrees provides the most stability in two K-wire fixations in this type of fracture repair.

Evaluation of pain in patients undergoing fixed dental appliance

Introduction: Pain is experienced by patients during various fixed orthodontic procedures such as placement of separators, insertion of arch wire and its activations, orthopedic appliances such as headgear, and debonding of the appliance. This study was formulated with the background that the level of pain sensation differs between conventional metal and ceramic brackets, arch wire being the same pain is an important aspect of oral health-related quality of life (OHRQOL). Understanding how patients' pain experiences during their treatment affect their quality of life (QOL) is important and the absence of pain/discomfort is important for achieving a high QOL. Aim and Objective: The objective of this study was to assess the relationship between pain and OHRQOL among patients wearing fixed orthodontic appliances and to evaluate whether patient motivation and counseling had an effect on the pain and discomfort. Materials and methods: The data collection was done , the obtained data were tabulated and entered in the MS excel sheet. Data collection were imported to SPSS, variable definition process was done using tables and graphical illustration.

Investigation of bypass-coupled double-pulsed directed energy deposition of Al–Mg alloys

Wire and arc additive manufacturing (WAAM) is a promising directed energy deposition (DED) technique for Al–Mg alloy parts. However, excessive workpiece heat input may limit its high productivity application. Hence, a bypass-coupled double-pulsed WAAM (BCDP-WAAM) method is developed to control the workpiece heat input without deteriorating productivity. High-speed camera images demonstrated that the arc and droplet trajectory were deflected towards the molten pool side in BCDP-WAAM. The observed strong-to-weak change in the arc necessitated a periodic insertion of the bypass-cathode wire into the molten pool for heat absorption. Spray and bridging transfers occurred in the anode and bypass-cathode wires, respectively. Current–voltage waveforms indicated that a dynamic current distribution between the workpiece and bypass-cathode wire was achieved in BCDP-WAAM, decreasing the workpiece current. Consequently, the workpiece heat input was decreased by 38.2 %. Owing to the twin-melted wires, the height and effective area were increased by 134.1 % and 149.0 % in BCDP-WAAM, respectively. The obtained electron back-scattered diffraction (EBSD) results indicated that the average grain size was reduced to 21 µm in BCDP-WAAM compared to a grain size of 36 µm in double-pulsed WAAM. This is attributed to the reduction in the workpiece heat input and the change in solidification induced by the bypass-cathode wire. The BCDP-WAAM enhanced the mechanical strength of the part. Furthermore, the ultimate tensile strength (UTS) and yield strength (YS) of the optimized part increased to 256 and 124 MPa in BCDP-WAAM, representing increments of 7.1 % and 14.8 %, respectively. The average micro-hardness was enhanced to 88.2 HV, representing an increase of 16.1 %. • The arc and droplet trajectory were deflected towards the molten pool side. • Bypass-cathode wire periodically inserted into the molten pool for absorbing heat. • A dynamic current distribution between workpiece and bypass-cathode wire occurred. • Reduced workpiece heat input and improved productivity simultaneously occurred.

TH1.3 Initial experience - Magseed for impalpable breast lesion localisation

Abstract Aims Impalpable breast lesions can be localised intraoperatively with Magseed and the Sentimag probe. Advantages over traditional wire localisation include reduced displacement, flexible insertion timescales, reduced patient anxiety and no requirement for radiation governance compared with radio-iodine seeds. We assess outcomes following introduction of Magseed localisation for impalpable breast lesions. Methods The first consecutive Magseeds inserted into breast lesions were identified from radiology records in a UK non-screening breast unit from July 2020 to March 2021. Indication for seed, intra-operative complications, margin involvement and re-excision rates were ascertained from electronic patient records. Caldicott / audit department approval was obtained. Results 63 Magseeds were inserted in 59 patients. Indications for seed localisation were invasive disease 81% (51/63), DCIS 8% (5/63) and B3 lesions 11% (7/63). 21% (10/47) of patients with invasive disease had received neoadjuvant chemotherapy. The median seed insertion to surgery time was 13 days. All patients underwent standard wide local excision or therapeutic mammoplasty. The lesion localisation rate and seed retrieval rate was 100%, however 2 magseeds (3%) were displaced during dissection. The margin re-excision rate was 15.3% (8/52) in patients with invasive and preinvasive disease. The upgrade rate for B3 lesions was 16.6% (1/6). Conclusions Magseed can be used to accurately localise impalpable breast lesions with acceptable margin re-excision rates. These findings during the learning curve would imply that this technique is easy to adopt. Insertion of seeds within 2 weeks of the operation is feasible and should improve radiologist's efficiency by avoiding on the day wire insertion.

EP-585 An Evaluation of Plastic Surgery Post-Operative Follow Up Planning in Line With Local Guidelines

Abstract Aim Post-operative follow up is an important aspect of surgical management plans. This audit evaluated whether the documentation of post operative follow up plans within plastic surgery operation notes, for three common operation categories, adhered to local guidelines. Methods This audit looked at one month's worth of follow up plans within a plastic surgery department in 2021. Specifically, the documentation within the operation note was audited for three operation categories: tendon repairs, K wire insertions and manipulations under anaesthetic (MUA). These operation notes were compared to local follow up guidelines and adherence was analysed. The results were presented within the department. Posters displaying the guidelines were created and placed in theatres, as well as circulated via WhatsApp. A second cycle was then undertaken. Results Each operation category guideline, consisted of various aspects of recommended follow up. Issues noted from the first cycle included an inaccuracy in the timing of follow up appointments. This was particularly evident in the MUA category where only 55% of cases having follow up appointments documented for the correct date. Following intervention, the K wire one week follow up appointment documentation improved from 40% to 67%. Conclusions Overall, an improvement in adherence to guidelines was observed during the second cycle following the intervention. The best impact was seen in the K-wire category, where all three aspects of that specific follow up guideline showed an increase in compliance. Publicising the follow up guidelines had a positive impact on the documentation of surgical follow up plans.

A Comparative Study of Internal Jugular Vein Cannulation under Ultrasound Guidance Using Short Axis or Long Axis View Approach

Background: Anaesthesiologists most commonly perform the procedure of internal jugular vein cannulation(IJV) in emergency and also in elective cases. With the use of ultrasound guidance placement of guide wire and catheter into the internal jugular vein has been made easy, safe and with less complications.
 Aims: The aim of the study was to compare IJ vein cannulation under ultrasound guidance with respect to Short and Long axis (SA and LA) view approaches.
 Methods: Patients who may require central venous cannulation for undergoing surgery and will be in intensive care unit were randomized using computer generated randomization for ultrasound guided cannulation into one of short axis and long axis (SA and LA) approaches group. Success rate of first pass, number of needle attempts made, guide wire insertion time, catheter placement time and complications were noted for each procedure.
 Results: Successful cannulation of IJV was achieved in all the patients. Significant results were not noted among the two groups with respect to demographic profile of the patient, catheter placement time, rate of carotid artery puncture. Whereas a significant result was noted in terms of success rate of first pass (97% in SA v/s 53% in LA, P-0.0001), number of needle attempts (mean of 1.05±0.18 in SA v/s 1.55±0.68 in LA, P-0.0001), guide wire insertion time (mean of 43.20±5.64 in SA v/s 74.83±39.36 in LA).
 Conclusion: We conclude from the above study that short axis view approach is better with respect to success rate of first pass, number of needle attempts and guide wire insertion time than long axis view approach for internal jugular vein cannulation under ultrasound guidance.

Accuracy of guide wire placement for femoral neck stabilization using 3D printed drill guides

BackgroundThe goal of stabilization of the femoral neck is to limit morbidity and mortality from fracture. Of three potential methods of fixation, (three percutaneous screws, the Synthes Femoral Neck System, and a dynamic hip screw), each requires guide wire positioning of the implant(s) in the femoral neck and head. Consistent and accurate positioning of these systems is paramount to reduce surgical times, stabilize fractures effectively, and reduce complications. To help expedite surgery and achieve ideal implant positioning in the geriatric population, we have developed and validated a surgical planning methodology using 3D modelling and printing technology.MethodsUsing image processing software, 3D surgical models were generated placing guide wires in a virtual model of an osteoporotic proximal femur sawbone. Three unique drill guides were created to achieve the optimal position for implant placement for each of the three different implant systems, and the guides were 3D printed. Subsequently, a trauma fellowship trained orthopedic surgeon used the 3D printed guides to position 2.8 mm diameter drill bit tipped guide wires into five osteoporotic sawbones for each of the three systems (fifteen sawbones total). Computed Tomography (CT) scans were then taken of each of the sawbones with the implants in place. 3D model renderings of the CT scans were created using image processing techniques and the displacement and angular deviations at guide wire entry to the optimal sawbone model were measured.ResultsAcross all three percutaneous screw guide wires, the average displacement was 3.19 ± 0.12 mm and the average angular deviation was 4.10 ± 0.17o. The Femoral Neck System guide wires had an average displacement of 1.59 ± 0.18 mm and average angular deviation of 2.81 ± 0.64o. The Dynamic Hip Screw had an average displacement of 1.03 ± 0.19 mm and average angular deviation of 2.59 ± 0.39o.ConclusionThe use of custom 3D printed drill guides to assist with the positioning of guide wires proved to be accurate for each of the three types of surgical strategies. Guides which are used to place more than 1 guide wire may have lower positional accuracy, as the guide may shift during multiple wire insertions. We believe that personalized point of care drill guides provide an accurate intraoperative method for positioning implants into the femoral neck.

Separation and trapping of magnetic particles by insertion of ferromagnetic wires inside a microchip: Proposing a novel geometry in magnetophoresis

In this study, by placing two ferromagnetic wires with different diameters inside the microchannel, a non-uniform magnetic field is generated. The magnetic force of this non-uniform field, separates different magnetic particles from each other and collects them in different parts of the channel. Using this system, we are able to collect and separate different particles from each other with an efficiency of 97%. This phenomenon depends on parameters such as wire diameter and its magnetic sensitivity, external magnetic field intensity, particle magnetic sensitivity, particle size and magnetic sensitivity of the carrier fluid. Here, these parameters are examined individually for magnetic particles (M-280 and M-450) and the optimum parameters are specified. Then, by comparing various cases, a system, for simultaneous separation and trapping is proposed. In addition, one of the magnetophoresis problems, which is interaction forces between magnetic particles investigated for the proposed system. The effects of effective parameters such as the distance between the wires and the fluid velocity are optimized to obtain maximum efficiency. Particle M-280 and M-450 are collected by wires with diameter of 100[μm] and 50[μm] respectively. The optimum distance between two wires is 800[μm], so their magnetic field distribution have positive effect on each other. Also, to maximize the system efficiency the fluid velocity is set to 11[mm/s]. By selecting these parameters as obtained values, the system efficiency is optimized. By changing wire diameter or magnetic field intensity, the proposed microchip can be used for separation and trapping of different particles.

A randomized, prospective, multicenter trial of 3D printing, a patient-specific surgical guide for breast-conserving surgery after neoadjuvant chemotherapy: Comparative evaluation according to the presence or absence of surgical guide.

576 Background: To obtain a clear resection margin during breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NCT), accurate targeting of the location and assessment extent of the tumor are essential. However, conventional targeting methods such as USG/MMG guided hook wire insertion have disadvantages in that they could only localize the tumor, not reflecting its extent. To assess this problem, we developed an MRI-based 3D printed breast surgical guide (3DP-BSG) and conducted a multicenter randomized clinical study to prove its clinical effectiveness. Methods: In this multicenter, randomized (1:1), controlled trial (KCT0004469), we assigned 566 patients who underwent NCT and planned to undergo BCS, to use customized 3DP-BSG for lumpectomy, or not to use 3DP-BSG for lumpectomy. We assumed that 3DP-BSG group achieve non-inferior outcomes compared with control group with conventional targeting method. The primary endpoint was the margin positivity of the first resected margin. Under the assumption that the proportion of margin positivity would be 23% in both groups, a total of 438 patients were calculated to have 80% power to establish non-inferiority with a margin of 10% at a one-sided significance level of 0.05. Efficacy was assessed in the intention-to-treat (ITT) population. Results: Between 2019 and 2021, 282 (49.8%) patients were assigned to 3DP-BSG group, and 284 (50.2%) patients were assigned to control group with conventional targeting method. The median age was 51 years. In the ITT analysis, first resected margin was positivity in 5 (2.1%) of 235 patients in 3DP-BSG group and 7 (2.9%) of 244 patients in control group (difference -1.15 [95% CI -3.58 to -1.28], pnon-inferiority <.0001). In the analysis of population excluding patients assessed as complete response (CR), first resected margin was positivity in 5 (3.40%) of 147 patients in 3DP-BSG group and 7 (4.8%) of 145 patients in control group (difference -1.43 [95% CI -5.25 to -2.40], pnon-inferiority <.0001). Most of the cases, marked areas with 3DP-BSG were partially different from those with conventional targeting method, and there were some cases where completely different areas were marked. In most of these cases, pathological CR made it difficult to compare the accuracy of the targeting methods, but in one case, a malignant tumor was diagnosed only in the 3DP-BSG targeting region. Even lesions that have been incorrectly targeted by conventional methods can be properly removed using 3DP-BSG, which is believed to be helpful in surgery. Conclusions: Lumpectomy using 3DP-BSG showed non-inferiority compared to the conventional targeting group, and the surgeon's satisfaction was higher by quantitatively presenting the extent of initial tumor. Clinical trial information: KCT0004469.

Abstract 354: Beiging Of Perivascular Adipose Tissue Regulates Its Inflammation And Vascular Remodeling

Background: Inflammation plays a primordial role in atherosclerosis. Perivascular adipose tissue (PVAT) that surrounds the vasculature has been reported to undergo phenotypic changes in response to vascular inflammation. However, regulatory roles of PVAT in vascular inflammation and subsequent pathological remodeling remain unclear. Methods and Results: Endovascular injury was generated by wire insertion into the mice femoral artery. Here, we showed that vascular injury induced the beiging (brown adipose tissue-like phenotype change) of PVAT, which fine-tunes inflammatory response and thus vascular remodeling as a protective mechanism. In a mouse model of endovascular injury, macrophages accumulated in PVAT, causing beiging phenotype change. Inhibition of PVAT beiging by adipose tissue-specific genetic ablation of PRDM16, a key regulator to beiging, exacerbated inflammation and vascular remodeling following injury. Local knockdown of Prdm16 in perivascular tissues of wild-type mice using small interfering RNA similarly exacerbated inflammation and vascular remodeling. Conversely, activation of PVAT beiging attenuated inflammation and pathological vascular remodeling. Single-cell RNA sequencing revealed that beige adipocytes abundantly expressed neuregulin 4 ( Nrg4 ) which critically regulated alternative macrophage activation. Furthermore, Nrg4 knockdown abolished the PVAT-mediated anti-inflammatory effects on macrophages. Importantly, significant beiging was observed in the diseased aortic PVAT in patients with acute aortic dissection. Conclusions: Endovascular injury induced the beiging of adjacent PVAT with macrophage accumulation, where NRG4 secreted from the beige PVAT facilitated alternative activation of macrophages, leading to the resolution of vascular inflammation. Our study demonstrated the pivotal roles of PVAT in vascular inflammation and remodeling and will open a new avenue for treating atherosclerosis.

Electric wire as an aid for masturbation: Report of a case with review of literature

Masturbation by insertion of electric wire is rarely reported in the literature. Here, we are presenting a case of electric wire in the urinary bladder, which was inserted as an aid to masturbation.

PD40-12 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE MINIMIZES RADIATION EXPOSURE IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY: A CADAVERIC STUDY WITH NOVICES

You have accessJournal of UrologyCME1 May 2022PD40-12 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE MINIMIZES RADIATION EXPOSURE IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY: A CADAVERIC STUDY WITH NOVICES Mitchell Humphreys, Kevin Wymer, Ben Chew, Janet Zhen, Fuad Elkhoury, Sri Sivalingam, Matthew Dunn, and Michael Borofsky Mitchell HumphreysMitchell Humphreys More articles by this author , Kevin WymerKevin Wymer More articles by this author , Ben ChewBen Chew More articles by this author , Janet ZhenJanet Zhen More articles by this author , Fuad ElkhouryFuad Elkhoury More articles by this author , Sri SivalingamSri Sivalingam More articles by this author , Matthew DunnMatthew Dunn More articles by this author , and Michael BorofskyMichael Borofsky More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002601.12AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Fluoroscopy plays a big role in endourologic stone procedures and intra-operative radiation exposure poses risks to the patient, surgeon, and staff. Fluoroscopic guidance is the most utilized imaging modality for obtaining access for percutaneous nephrolithotomy (PCNL). Radiation usage may also be higher by urologists who are less experienced. In this study, radiation use is compared while gaining percutaneous access in a cadaveric model, using either fluoroscopy or a novel robotic-assisted electromagnetic (EM) method in a cohort of novice urologist. METHODS: Seven novices (individuals who use IR for access, or gain percutaneous access <24 times/year, or have gained access <30 times after training) used robotic-assisted EM-guidance provided by the Monarch® Platform, Urology (Auris Health, Inc., Redwood City, CA) to obtain upper pole, mid kidney, and lower pole access in a modified supine position vs. the same tasks in a prone position using fluoroscopy in a human cadaver. Total radiation time and dosage, defined as from pyelogram to wire insertion, and access radiation time and dosage, defined as from needle insertion to wire insertion, were measured. Statistical comparisons were made using paired t-tests. RESULTS: Robot-assisted EM-guidance decreased total radiation time (0.11±0.01 min vs. 1.30±0.33 min, mean ±SEM, p<0.05) and total radiation dosage (1.00±0.15 mGy vs. 5.43±0.88 mGy, p<0.01), compared to fluoroscopy-guided navigation (Figure 1). Additionally, robotic-assisted EM-guidance reduced access radiation time (0.08±0.05 min vs. 1.08±0.24 min, p<0.01) and access radiation dosage (0.25±0.11 mGy vs. 4.25±0.86 mGy, p<0.01) compared to fluoroscopic-guidance. CONCLUSIONS: Robotic-assisted EM-guidance provided by the Monarch® Platform robotic system decreased radiation exposure when compared to fluoroscopic-guidance during percutaneous access in novice urologists with limited access experience. Keeping in mind the principals of ALARA, these limited data suggest that this novel technology could have significant benefits for patients and providers alike. Source of Funding: Johnson & Johnson © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e688 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mitchell Humphreys More articles by this author Kevin Wymer More articles by this author Ben Chew More articles by this author Janet Zhen More articles by this author Fuad Elkhoury More articles by this author Sri Sivalingam More articles by this author Matthew Dunn More articles by this author Michael Borofsky More articles by this author Expand All Advertisement PDF DownloadLoading ...

Enhanced pyrolysis of woody biomass under interaction of microwave and needle-shape metal and its production properties

Pyrolysis is one of the routes to value-added utilization of biomass, and the pyrolysis process can be enhanced with microwave heating, especially in the presence of catalyst. However, the catalysts used for biomass pyrolysis are usually in form of powder or grain, which leads to a problem that the catalysts are hard to separate from bio-char after the pyrolysis process. Based on this issue, the development of an enhanced microwave-assisted pyrolysis method without catalyst is of great significance. Therefore, this study proposes the method of microwave-enhanced pyrolysis of woody biomass via the interaction of microwave and needle-shape metal (iron-wire). In the paper, the pyrolysis characteristics and kinetic behaviors in the presence and in the absence of iron-wire were investigated, using pine sawdust and the mixture of biomass components as the material. Moreover, the properties of pyrolysis products with and without microwave-metal interaction were characterized, and the mechanism of microwave-metal interaction on the enhancement of pyrolysis was also analyzed. The results showed that the value of Ea reduced by 50% with microwave-metal interaction and the process under microwave-metal interaction was more conducive to the generation of bio-gas, with the yield of 62.43 wt%. Microwave-metal interaction increased ID/IG value of bio-char from 0.69 to 0.92, indicating an improvement of graphite degree, and decreased the content of aromatic compounds in bio-oil by 11.8%. The enhanced pyrolysis process is due to the increased electromagnetic distribution density after the insertion of iron wire into microwave and even microwave discharge occurred at the initial stage.

Fluoroless left atrial access for radiofrequency and cryoballoon ablations using a novel radiofrequency transseptal wire

PurposeConventional catheter ablation for atrial fibrillation requires fluoroscopy, which has inherent risks of radiation exposure to patients and medical staff. Optimization of fluoroscopy parameters and use of three-dimensional electroanatomic mapping (EAM) and intracardiac echocardiography (ICE) have helped to reduce radiation exposure; however, despite growing evidence, there are still concerns about safety and added procedure time associated with fluoroless procedures, particularly in left-sided ablations, due to the potential risk of complications. Herein, we report our initial experience using a radiofrequency (RF) wire for completely fluoroless radiofrequency ablation (RFA) and cryoballoon ablation (CBA).MethodsA retrospective analysis was conducted on ablation procedures for various cardiac arrhythmias performed non-fluoroscopically at two centers using the VersaCross RF wire transseptal system under EAM and ICE guidance.ResultsA total of 72 and 54 patients underwent RFA and CBA, respectively, successfully without any procedural complications. Transseptal access time for RFA was 14.5 ± 6.6 min from procedure start (including sheath and catheter placements ± right-sided ablation) or 2.8 ± 1.0 min from RF wire insertion into the femoral introducer. Transseptal access time for CBA was 19.2 ± 11.7 min from procedure start (including sheath and catheter placements ± right-sided ablation) or 3.5 ± 1.6 min from RF wire insertion into the femoral introducer. Average procedure time was 104.4 ± 38.0 min for RFA and 91.1 ± 22.1 min for CBA.ConclusionsA RF wire can be used to achieve completely fluoroless transseptal puncture safely and effectively while improving procedural efficiency in both RFA and CBA.

The silver-coated sponge spacer and multiwalled carbon nanotube-dragon skin electrodes for cushion-type nanocomposite pressure sensor array

Prolonged sitting in an unhealthy posture can cause various health ailments. Especially, wheelchair users and office workers suffer from pressure ulcer and chronic back pain. Here we report a cushion-type 20 × 20 pressure sensor array made by the low-cost simple scalable method. The soft electrode is made of multiwalled carbon nanotubes and dragon skin matrix. The resistance of the electrode is dramatically decreased by the insertion of a copper wire. The silver-coated polyurethane sponge provides the piezoresistive sensing mechanism and significantly improves the sensor response. The continuous sensing range (0–70 kPa) is sufficient for sitting posture analysis, and the sensitivity is as high as 0.10 kPa-1 in the range of 0–10 kPa. The signal is processed using a single board microcontroller, and data are transmitted to a mobile device wirelessly. The sequential voltage supply and signal read minimize the number of voltage supply and analog-to-digital conversion ports in the microcontroller, and a modified conductance matrix algorithm is designed to completely eliminate crosstalk effect of the sensor array. The pressure sensor successfully recognizes various sitting postures, including optimal and left/right/forward leaning, and may find immediate rehabilitation and health care applications.

Simple surgical technique for epicardial pacemaker wire preparation and insertion

Epicardial pacing wire (EPW) insertion is an integral part of open heart surgery. However, the use of EPW insertion is also associated with complications such as bleeding, tamponade, arrhythmias, and occasionally even death of the patient. Various techniques have been described for preparing, placing, and removing EPW. We present our simple, yet effective technique of preparing, inserting, and removing EPW where the incidence of complications is nil.

Tratamento de cicatriz de acne com peelings, subcisão, fios de polidioxanona (PDO) e fibrina rica em plaquetas – relato de caso

Acne scarring results from tissue loss and increased tissue proliferation. Atrophic scarring is caused by the loss of collagen that occurs in the inflammatory process of acne. All scars have psychological consequences, as they can affect self-esteem and cause physical pain when moving the affected area. Chemical peels are widely used to treat acne and acne scarring. They cause an injury to the skin or accelerated exfoliation, induced by caustic agents that cause controlled damage, followed by the release of cytokines and mediators of inflammation, resulting in thickening of the epidermis, collagen deposition, reorganization of structural elements and increase in dermal volume. Among the therapeutic modalities of acne scars, subcision is a simple and safe procedure. Subcision frees the scar surfaces and induces the formation of connective tissue directly below the scar. Another method used is the application of plasma rich in platelets and fibrin that release growth factor, essential for wound healing and synthesis of extracellular matrix remodeling. Polydioxanone (PDO) threads induce collagen production, increasing the number of fibroblasts in the tissue where it was inserted. This work presented a case of acne scarring, firstly treated with two applications of 10% ATA peeling and 10% retinoic acid. Then a subcision was made with a duckbill cannula and insertion of PDO wires with PRP in the scar region.

Pin site infection: A systematic review on how surgical techniques applying wires and half-pins affects pin site infection

Introduction: Pin site infection continues to be a very common problem when treating patients with external fixators. Wire and half-pin insertion technique may influence the risk of developing a pin site infection and the aim of this study is to investigate existing literature in relation to this. Methods: A systematic review of the literature reporting on surgical techniques in relation to pin site infection was conducted. Studies evaluating the effect of a surgical technique with proposed preventive measures to minimize pin site infection in adults and children undergoing an external fixation for trauma or reconstruction were eligible for inclusion. The primary outcome was pin site infection rate. MEDLINE, EMBASE, CINAHL, Google Scholar, and the Cochrane Central Register of Controlled Trials were searched for the period 1970 to August 2021. Study quality was assessed using the modified Downs and Black checklist. A narrative synthesis was undertaken. Results: Two studies describing two different surgical methods were found eligible for inclusion (one cross-sectional study and one prospective cohort). Neither of the two surgical techniques seemed to affect the pin site infection rate. Conclusion: Literature on this topic is sparse, and at present, there is no convincing evidence to support that one surgical technique applying wires and pins is preventive in relation to pin site infection.

Comparative Assessment of Functional Outcomes of Surgical Treatment in Patients with Distal Radial Fractures.

Unstable and comminuted distal radial fractures require surgical treatment by percutaneous insertion of Kir-schner wires, open reduction and fixation with a non-locking or locking plate or with an external device. The aim of this paper was to try to answer the following question: are there differences in functional treatment outcomes in patients after surgery with the use of Kirschner wires vs LCP plate fixation? The study group included 100 patients after surgical treatment by closed reduction and simple fixation with Kirschner wires (50 patients) and by open reduction and LCP locking plate fixation (50 patients). The study assessed the following parameters: global grip strength, pain severity in a VAS scale, range of motion, functional status of the wrist based on the Fernandez classification, quality of life according to the QuickDASH score, and the frequency of complications. These parameters were assessed at 6 and 12 months after surgery. An assessment of the treatment outcomes at 6 and 12 months after surgery showed statistically significant differences between the treatment methods in the following parameters: pain severity, global grip strength and range of motion in the sagittal plane. A comparison of the functional status of the wrist at 6 and 12 months between the groups showed considerably worse results in the Kirschner wire fixation group. The frequency of postoperative complications at 12 months was 6% in the Kirschner wire fixation group and 2% in the LCP plate fixation group. 1. Treatment outcomes were better in patients with distal radial fractures managed with LCP plate fixation. 2. The use of LCP plate fixation predisposes pa-tients to better ranges of mobility in the sagittal plane in the radiocarpal joint. 3.The values of global grip strength were higher in the group treated with LCP plate fixation. 4. Patients treated with LCP plates have better limb function and quality of life and lower pain intensity after treatment completion. 5. The number of complications was higher in pa-tients treated with Kirschner wire fixation.

Validity of performance factors used in recent studies on heat transfer enhancement by surface modification or insert devices

Based on literature survey, the performance factors were used in 62 articles which have been published in 2021 in International Journal of Heat and Mass Transfer, International communications in Heat and Mass Transfer, International Journal of Thermal Sciences and Applied Thermal Engineering, to evaluate the heat transfer enhancement by geometry modification or insertion of tapes, wires or turbulence promoters under identical pumping power. However, the validity of the performance factors was not examined yet. The heat transfer rate in a periodic fully developed region of a circular duct with periodic annular baffle plates was numerically obtained. Comparing the heat transfer rate with that of a circular smooth duct, the validity of the performance factors used in previous studies was examined. It was found that the performance factors used in the previous studies are not valid for the evaluation of heat transfer enhancement. Furthermore, this paper shows that the direct comparison of heat transfer rates without the assumptions of equal surface area and the equal temperature difference is suitable for the evaluation of heat transfer enhancement.