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The fabrication and switching characteristics of large diameter (1mm) Ga2O3 heterojunction rectifiers with bilayers of NiO as the p-type layer are reported. The band alignment shows this is a staggered-gap system. Selective wet and dry etching was developed to allow fabrication of vertical geometry heterojunction rectifiers. A forward current of 2.5 Amperes was achieved, with a reverse breakdown voltage of 2.7 kilovolts. The on/off ratio was above 108 over a broad range of switching voltages, with a measurement-limited reverse recovery time of 100 nanoseconds.

Patterning of NiO/Ga2O3 heterojunctions requires development of selective wet and dry etch processes. Solutions of 1:4 HNO3:H2O exhibited measurable etch rates for NiO above 40 °C and activation energy for wet etching of 172.9 kJ.mol−1 (41.3 kCal.mol−1, 1.8 eV atom−1), which is firmly in the reaction-limited regime. The selectivity over β-Ga2O3 was infinite for temperatures up to 55 °C. The strong negative enthalpy for producing the etch product Ga(OH)4 suggests HNO3-based wet etching of NiO occurs via formation and dissolution of hydroxides. For dry etching, Cl2/Ar Inductively Coupled Plasmas produced etch rates for NiO up to 800 Å.min−1, with maximum selectivities of β-Ga2O3. The ion energy threshold for initiation of etching of NiO was ∼55 eV and the etch mechanism was ion-driven, as determined the linear dependence of etch rate on the square root of ion energy incident on the surface.

There is increasing interest in the alpha polytype of Ga2O3 because of its even larger bandgap than the more studied beta polytype, but in common with the latter, there is no viable p-type doping technology. One option is to use p-type oxides to realize heterojunctions and NiO is one of the candidate oxides. The band alignment of sputtered NiO on α-Ga2O3 remains type II, staggered gap for annealing temperatures up to 600°C, showing that this a viable approach for hole injection in power electronic devices based on the alpha polytype of Ga2O3. The magnitude of both the conduction and valence band offsets increase with temperature up to 500°C, but then are stable to 600°C. For the as-deposited NiO/ α-Ga2O3 heterojunction, ΔEV=-2.8 eV and ΔEC= 1.6 eV, while after 600°C annealing the corresponding values are ΔEV=-4.4 eV and ΔEC= 3.02 eV. These values are 1-2 eV larger than for the NiO/β-Ga2O3 heterojunction.

NiO/ β-(Al x Ga1-x )2O3 /Ga2O3 heterojunction lateral geometry rectifiers with diameter 50-100 µm exhibited maximum reverse breakdown voltages >7kV, showing the advantage of increasing the bandgap using the β-(Al x Ga1-x )2O3 alloy. This Si-doped alloy layer was grown by Metal Organic Chemical Vapor Deposition with an Al composition of ~21 %. On state resistances were in the range 50-2180 Ω.cm2, leading to power figures-of-merit up to 0.72 MW.cm-2. The forward turn-on voltage was in the range 2.3-2.5 V, with maximum on/off ratios >700 when switching from 5V forward to reverse biases up to -100V. Transmission line measurements showed the specific contact resistance was 0.12 Ω.cm2. The breakdown voltage is among the highest reported for any lateral geometry Ga2O3-based rectifier.

Background: Currently, the standard of treatment for trimalleolar (TM) fracture is osteosynthesis through open reduction and internal fixation (ORIF). This study assessed whether arthroscopically assisted reduction and minimally invasive surgery (AARMIS) can be an alternative surgical method for TM fractures. Methods: This retrospective cohort study included 49 patients with TM that were surgically treated. 27 patients received ORIF and 22 patients underwent AARMIS . At baseline, we recorded the patient’s demographic features, fracture pattern (AO-OTA and Haraguchi classification), and surgical method. For postoperative results, we examined the patient’s radiographic outcome, including time to union, quality of fracture reduction, as well as functional outcomes (American Orthopaedic Foot & Ankle Society ankle hindfoot score, ankle range of motion, and visual analog scale of pain) and perioperative complications. Results: At mean follow-up of 46.6[Formula: see text] (ORIF) and 36.4[Formula: see text] months (AARMIS), both groups had comparable radiographic outcomes. No significant difference in rates of early ankle OA were detected. In terms of functional outcome, VAS pain and AOFAS score at postoperative day 3, postoperative month 3, and at final follow-up were not different. In terms of range of motion, we did not find a significant difference in mean range of motion. Conclusion: Patients with TM fractures treated with AARMIS achieved satisfactory results and was not significantly different in radiographic and functional performance compared with ORIF. Level of Evidence: Level III, retrospective cohort study.

Blood testing is a crucial medical application. In this study, we applied Raman spectroscopy to test blood samples and obtained complete biological information, including the main components and compositions in these samples. Short-wavelength (532-nm green light) Raman scattering spectroscopy was conducted on samples of normal blood, abnormal blood in 3 types of preparation including whole blood, plasma, and serum, and the underlying information reflected by the biological characteristics detected in each sample type were analyzed. Raman spectroscopy results indicated that normal blood had high hemoglobin content, which suggests that hemoglobin is a major component of blood. Hemoglobin affects blood oxygen level. The characteristic peaks of hemoglobin were observed at 690, 989, 1015, 1182, 1233, 1315, and 1562–1649 cm−1. Analysis of plasma and serum samples indicated the presence of β-carotene, which exhibited characteristic peaks at 1013, 1172, and 1526 cm−1. In addition, surface-enhanced Raman spectroscopy was used to collect biological signals that are difficult to obtain in conventional Raman spectroscopy, including those of small molecules such as hormones, antibodies, and enzymes. Changes in biological information collected in this manner can be used as a basis for potentially diagnosing clinical diseases.

Vertical geometry NiO/β n-Ga2O/n+ Ga2O3 heterojunction rectifiers with contact sizes from 50 to 200 μm diameter showed breakdown voltages (VB) up to 7.5 kV for drift region carrier concentration of 8 × 1015 cm−3. This exceeds the unipolar 1D limit for SiC and was achieved without substrate thinning or annealing of the epi layer structure. The power figure-of-merit, VB2/RON, was 6.2 GW cm−2, where RON is the on-state resistance (9.3–14.7 mΩ cm2). The average electric field strength was 7.56 MV/cm, approaching the maximum for β-Ga2O3. The on–off ratio switching from 5 to 0 V was 2 × 1013, while it was 3 × 1010–2 × 1011 switching to 100 V. The turn-on voltage was in the range 1.9–2.1 V for the different contact diameters, while the reverse current density was in the range 2 × 10−8–2 × 10−9 A cm−2 at −100 V. The reverse recovery time was 21 ns, while the forward current density was >100 A/cm2 at 5 V.

NiO/β-Ga2O3 vertical rectifiers exhibit near-temperature-independent breakdown voltages (VB) of >8 kV to 600K. For 100 µm diameter devices, the power figure of merit (VB)2/ RON, where RON is the on-state...

Background: Adult acquired flatfoot deformity (AAFD) and hallux valgus (HV) are common foot and ankle deformities. Few studies have reported the changes in radiographic parameters of HV after reconstructive surgery for AAFD. This study aimed to evaluate the changes in radiographic parameters of HV and analyze the risk factors for increased HV after correction of AAFD. Methods: Adult patients with flexible AAFD who underwent similar bony procedures including medializing calcaneal osteotomy and Cotton osteotomy were included. Radiographic parameters were measured on weightbearing radiographs preoperatively, postoperatively, and at the final follow-up. Patients were divided into hallux valgus angle (HVA) increased and HVA nonincreased groups; logistic regression analysis was performed to identify risk factors affecting increased HV. Results: Forty-six feet of 43 patients were included. After AAFD reconstructive surgery, the tibial sesamoid position improved by 1 grade, but the HVA increased 4 degrees in average. Further, 21 of 46 feet (46%) showed an HVA increase ≥5 degrees immediately after AAFD correction surgery. Preoperative talonavicular coverage angle Conclusion: In this case series, using plain radiographs to measure standard parameters of foot alignment, we found the association between AAFD correction and HV deformity measures somewhat paradoxical. Correction of overpronation of the hindfoot and midfoot appears to improve the first metatarsal rotational deformity but may also increase HVA. A lower preoperative talonavicular coverage angle was associated with an increase of the HVA after surgery. Level of Evidence: Level IV, case series study.

Optimized vertical heterojunction rectifiers with a diameter of 100 µm, consisting of sputter-deposited p-type NiO forming a p–n junction with thick (10 µm) Ga2O3 drift layers grown by halide vapor phase epitaxy (HVPE) on (001) Sn-doped (1019 cm−3) β-Ga2O3 substrates, exhibited breakdown voltages >8 kV over large areas (>1 cm2). The key requirements were low drift layer doping concentrations (9 GW.cm−2. The devices showed an almost temperature-independent breakdown to 600 K. These results show the remarkable potential of NiO/Ga2O3 rectifiers for performance beyond the limits of both SiC and GaN. The important points to achieve the excellent performance were: (1) low drift doping concentration, (2) low power during the NiO deposition and (3) formation of a guard ring.

NiO/β-(Al xGa1− x)2O3/Ga2O3 heterojunction lateral geometry rectifiers with diameter 50–100 μm exhibited maximum reverse breakdown voltages >7 kV, showing the advantage of increasing the bandgap using the β-(Al xGa1− x)2O3 alloy. This Si-doped alloy layer was grown by metal organic chemical vapor deposition with an Al composition of ∼21%. On-state resistances were in the range of 50–2180 Ω cm2, leading to power figures-of-merit up to 0.72 MW cm−2. The forward turn-on voltage was in the range of 2.3–2.5 V, with maximum on/off ratios >700 when switching from 5 V forward to reverse biases up to −100 V. Transmission line measurements showed the specific contact resistance was 0.12 Ω cm2. The breakdown voltage is among the highest reported for any lateral geometry Ga2O3-based rectifier.

Background:This retrospective study aimed to describe the techniques and results of distal metatarsal segmental shortening (DMSS) for the treatment of chronic irreducible metatarsophalangeal (MTP) dislocation of lesser toes.Methods:We retrospectively reviewed patients who underwent DMSS for chronic dislocation of MTP joints of lesser toes between January 2010 and December 2017 with follow-up of at least 24 months. Demographic data, radiographic measurements, functional outcomes, and complications were analyzed. Furthermore, the results of patients with short segment of shortening (group I, Results:Union was observed in 42 metatarsals (97.7%). Mean American Orthopaedic Foot & Ankle Society scale scores improved significantly from 42.2 (range, 15-65) preoperatively to 79.1 (range, 52-90) ( P < .001). Mean visual analog scale pain score improved significantly from 5.0 (range, 1-9) preoperatively to 1.8 (range, 0-6) ( P < .001). Complications included 1 nonunion, 1 osteonecrosis, 3 metatarsal angulation, 4 recurrent instability, 4 symptomatic osteoarthritis, 3 transfer metatarsalgia, and 1 floating toe. Group I included 23 MTP joints and group II included 20 MTP joints. There was no significant difference in clinical outcomes and complications between the 2 groups.Conclusion:DMSS was a reliable procedure for the treatment of chronic irreducible dislocated MTP joint of lesser toes. It provided satisfactory surgical outcomes and a low rate of postoperative complications, regardless of length of metatarsal shortening.Level of Evidence:Level III, retrospective comparative study.

PURPOSE To evaluate the surgical outcome in terms of radiographic measurements, functional outcomes, and complications following arthroscopic ankle arthrodesis (AAA) in patients 60 years of age or older, and to compare the results of patients with mildly deformed ankle with those of patients with severely deformed ankle. METHODS We retrospectively reviewed patients who underwent AAA with 3 cannulated screws between January 2008 and December 2017 and followed postoperatively for at least 24 months. All included patients were 60 years of age or older. Demographic data and radiographic and functional outcomes were compared between patients with coronal deformity of less than 15° (group I) and those with a deformity equal to or greater than 15 degrees (group II). RESULTS A total of 41 patients with a mean age of 70.6 years were included (group I, n = 26; group II, n = 15) and mean follow-up was 51.4 months. Group II had significantly more severe preoperative coronal deformity of tibiotalar angle than group I (20.1 ± 2.9 vs 6.6 ± 4.1°, P < .01). Near-normal tibiotalar alignment was achieved postoperatively in both groups (group I, 3.4 ± 3.3 vs group II, 4.7 ± 3.1°, P = .227). Union was achieved in 39 (95.1%) patients with 2 cases in group I experiencing non-union. Union rate, mean American Orthopaedic Foot and Ankle Society ankle-hindfoot scale, and visual analog scale pain scores were not significantly different between the 2 groups at final follow-up. CONCLUSIONS AAA is a reliable procedure for end-stage ankle arthritis in patients 60 years of age or older resulting in a high union rate, encouraging radiographic and functional outcomes, and a low complication rate, even in cases with severe preoperative deformity. In addition, arthroscopic intra-articular malleolar osteotomy was a useful technique for correcting severe coronal deformity in our series. LEVEL OF EVIDENCE Level III, retrospective comparative study.

Background The aim of this study was to compare the radiographic and functional results between fixation and non-fixation in the Cotton osteotomy for the treatment of adult acquired flatfoot. Methods A retrospective, case-controlled study of consecutive stage IIB posterior tibial tendon dysfunction (PTTD) patients treated with the same bony reconstructive surgery including cotton osteotomy between 2013 and 2017. Meary’s angle, the medial arch sag angle (MASA), and medial cuneiform cobb angle (MCCA) were evaluated pre-operation, at first weight bearing after surgery, and 12 months post operation. Results Forty feet were included in the study. The cotton osteotomy utilized screw fixation (n = 20) or non-fixation technique (n = 20). No significant differences between groups were found in pre-operative and follow-up radiographic parameters, union rate, and functional results. Conclusion The non-fixation with press fit technique is a reliable procedure for Cotton osteotomy and as effective as screw fixation. Level of evidence Level III, case control study

Background: The deltoid ligament (DL) is an important stabilizer of the ankle. DL injury of varying severity can occur alone or with syndesmotic injury and fibular fracture. Limited diagnostic tools are available to assess DL injury quantitatively. Purpose: To establish an arthroscopic quantitative assessment of DL injury and to compare its performance with that of external rotation stress (ERS) and gravity stress (GS) radiography. Study Design: Controlled laboratory study. Methods: In total, 24 cadaveric lower extremities were divided into 4 groups: group 1 consisted of intact DL, group 2 of superficial DL disruption, group 3 of deep DL disruption, and group 4 of complete DL (superficial and deep) disruption. All specimens underwent sequential sectioning of syndesmotic ligaments, and medial clear space (MCS) was measured with ankle arthroscopy, ERS radiography, and GS radiography at different stages of syndesmotic sectioning. Results: For noninjured deltoid (group 1) and injured deltoid (groups 2-4), area under the receiver operating characteristic curve (AUC) of measurement of MCS was 0.939 for arthroscopy, 0.932 for ERS radiography, and 0.874 for GS radiography, with a significant difference between arthroscopy and GS radiography ( P = .014). For incomplete deltoid injury (groups 1-3) and complete deltoid injury (group 4), the AUC of MCS was 0.811 for arthroscopy, 0.656 for ERS radiography, and 0.721 for GS radiography, with a significant difference between arthroscopy and ERS radiography ( P < .001) and between arthroscopy and GS radiography ( P = .035). For all stages of syndesmotic sectioning, cutoff values of arthroscopic MCS with intact fibula were ≤2.5 mm for intact DL, between 2.5 and 3.5 mm for partial DL injury (superficial or deep), and ≥3.5 mm for complete DL injury. Arthroscopy was unable to detect a difference between superficial deltoid injury (group 2) and deep deltoid injury (group 3) in partial DL injury, with a measured MCS between 2.5 and 3.5 mm. The intraclass correlation coefficient of interrater reliability was 0.975 for arthroscopy, 0.917 for ERS radiography, and 0.811 for GS radiography. Conclusion: Arthroscopic MCS measurement can differentiate intact DL, partial DL injury, and complete DL injury. Compared with ERS and GS radiography, arthroscopic MCS measurement has greater accuracy with excellent interrater reliability. Clinical Relevance: For patients with suspected DL injury, arthroscopic MCS is useful for determining deltoid lesion severity based on defined cutoff values for consideration in preoperative planning to improve surgical outcomes.

Background The aim of this study was to compare two techniques for the surgical treatment of diaphyseal fractures in the adult humerus: double-crossed retrograde elastic stable intramedullary nailing (DCR-ESIN) and limited-contact dynamic compression plate (LC-DCP). Methods This was a retrospective study conducted at a single hospital. We included 122 patients with diaphyseal fractures of the humerus who had received DCR-ESIN or LC-DCP from January 2011 to January 2017. We compared union rates, union times, disabilities of the arm, shoulder, and hand (DASH) scores at the postoperative 1-year follow-up, and complications between the two groups. Results Plating management was performed in 63 patients, while DCR-ESIN was performed in 59 patients. The union rate was higher in the DCR-ESIN group than in the LC-DCP group (100% vs. 90.5%; p = 0.052). The union time was shorter in the DCR-ESIN group than in the LC-DCP group (12.0 weeks vs. 14.8 weeks; p p p p = 0.006). At the 1-year follow-up, the DCR-ESIN group had better DASH scores than the LC-DCP group (p = 0.014). Conclusions The DCR-ESIN technique, used to treat diaphyseal fractures of the humerus, has shorter operative times, less intra-operative blood loss, shorter union times, and better functional outcomes at 1-year follow-up than the LC-DCP technique. DCR-ESIN may be an alternative method for the surgical treatment of diaphyseal humeral fractures in adults.

NiO/Ga2O3 heterojunction rectifiers were exposed to 1 Mrad fluences of Co-60 γ-rays either with or without reverse biases. While there is a small component of Compton electrons (600 keV), generated via the interaction of 1.17 and 1.33 MeV gamma photons with the semiconductor, which in turn can lead to displacement damage, most of the energy is lost to ionization. The effect of the exposure to radiation is a 1000× reduction in forward current and a 100× increase in reverse current in the rectifiers, which is independent of whether the devices were biased during this step. The on–off ratio is also reduced by almost five orders of magnitude. There is a slight reduction in carrier concentration in the Ga2O3 drift region, with an effective carrier removal rate of −1. The changes in electrical characteristics are reversible by application of short forward current pulses during repeated measurement of the current–voltage characteristics at room temperature. There are no permanent total ionizing dose effects present in the rectifiers to 1 Mad fluences, which along with their resistance to displacement damage effects indicate that these devices may be well-suited to harsh terrestrial and space radiation applications if appropriate bias sequences are implemented to reverse the radiation-induced changes.

The characteristics of sputtered NiO for use in pn heterojunctions with Ga2O3 were investigated as a function of sputtering parameters and postdeposition annealing temperature. The oxygen/ nickel and Ni2O3/NiO ratios, as well as the bandgap and resistivity, increased as a function of O2/Ar gas flow ratio. For example, the bandgap increased from 3.7 to 3.9 eV and the resistivity increased from 0.1 to 2.9 Ω cm for the O2/Ar ratio increasing from 1/30 to 1/3. By sharp contrast, the bandgap and Ni2O3/NiO ratio decreased monotonically with postdeposition annealing temperatures up to 600 °C, but the density of films increased due to a higher fraction of NiO being present. Hydrogen is readily incorporated into NiO during exposure to plasmas, as delineated by secondary ion mass spectrometry measurements on deuterated films. The band alignments of NiO films were type II-staggered gaps with both α- and β-Ga2O3. The breakdown voltage of NiO/β-Ga2O3 heterojunction rectifiers was also a strong function of the O2/Ar flow ratio during deposition, with values of 1350 V for 1/3 and 830 V for 1/30.

This study investigated a SARS-CoV-2 virus detection mechanism using dry-stored disposable strips. The accuracy of this sensing platform is as good as polymerase chain reaction (PCR) with a detection time of fewer than 30 s. SARS-CoV-2 antibodies were biofunctionalized on disposable strips similar to glucose detection strips to detect the presence and concentrations of SARS-CoV-2 in saliva samples. Eight 1 ms electric pulses were sent through the sensor strip with a saliva sample in its microfluidic chamber. A circuit board embedded with MOSFET was also employed to amplify the detected signals and convert the signal to digital readings displayed on an LCD screen. The COV-antibody functionalized disposable strips were stored in a dry condition for at least one day before analyzing clinical human saliva samples with known cycling threshold (Ct) values confirmed with conventional PCR tests. Results demonstrate our system is capable of showing qualitative positive or negative results within 30 s and providing quantitative SARS-CoV-2 concentrations in terms of Ct values in 5 min.

The temperature-dependent behavior of on/off ratio and reverse recovery time in vertical heterojunction p-NiO/β n-Ga2O/n+ Ga2O3 rectifiers was investigated over the temperature range of 25–300 °C. The device characteristics in forward bias showed evidence of multiple current transport mechanisms and were found to be dependent on the applied bias voltages and temperatures. The on–off ratio decreased from 3 × 106 at 25 °C to 2.5 × 104 at 300 °C for switching to 100 V reverse bias. For 200 μm diameter rectifiers, the reverse recovery time of ∼21 ns was independent of temperature, with the Irr monotonically increasing from 15.1 mA at 25 °C to 25.6 mA at 250 °C and dropping at 300 °C. The dI/dt increased from 4.2 to 4.6 A/ μs over this temperature range. The turn-on voltage decreased from 2.9 V at 25 °C to 1.7 V at 300 °C. The temperature coefficient of breakdown voltage was negative and does not support the presence of avalanche breakdown in NiO/β-Ga2O3 rectifiers. The energy loss during switching from 100 V was in the range 23–31 μJ over the temperature range investigated.

There is increasing interest in the alpha polytype of Ga2O3 because of its even larger bandgap than the more studied beta polytype, but in common with the latter, there is no viable p-type doping technology. One option is to use p-type oxides to realize heterojunctions and NiO is one of the candidate oxides. The band alignment of sputtered NiO on α-Ga2O3 remains type II, staggered gap for annealing temperatures up to 600 °C, showing that this is a viable approach for hole injection in power electronic devices based on the alpha polytype of Ga2O3. The magnitude of both the conduction and valence band offsets increases with temperature up to 500 °C, but then is stable to 600 °C. For the as-deposited NiO/α-Ga2O3 heterojunction, ΔEV = −2.8 and ΔEC = 1.6 eV, while after 600 °C annealing the corresponding values are ΔEV = −4.4 and ΔEC = 3.02 eV. These values are 1−2 eV larger than for the NiO/β-Ga2O3 heterojunction.

Biomimetic micro- and nanotechnology have substantially grown in recent years, contributing to significant progress in the pharmaceutical and biomedical domains [...]

BCl3 is an attractive plasma etchant for oxides because it is a Lewis acid used to scavenge native oxides on many semiconductors due to the strong B–O bonding. We investigated BCl3-based dry etching of the NiO/Ga2O3 heterojunction system. BCl3/Ar Inductively Coupled Plasmas produced maximum etch rates for NiO up to 300 Å.min−1 and 800 Å.min−1 for β-Ga2O3 under moderate plasma power conditions suitable for low damage pattern transfer. The selectivity for NiO: Ga2O3 was 2O3 had a stronger chemical component, without a well-defined ion energy threshold. The as-etched NiO and Ga2O3 surfaces show chlorine residues, which can be removed on both materials by the standard 1NH4OH: 10H2O or 1HCl: 10H2O rinses used for native oxide removal. According to the location of the Cl 2p3/2 peak, the Cl is ionically bonded.

A SARS-CoV-2 rapid detection technology employed commercially available test strips similar to the blood glucose test strips were developed with a detection time of 30 sec and the sensitivity as good as polymerase chain reaction (PCR). The analytical specificity of this technology was also investigated by testing the cross-reactivity and microbial interference on this biosensor platform using FDA suggested 31 different contaminants. Variants of SARS-CoV-2 have mutated along with the worldwide spread of the pandemic. Currently, the most common detection methods are PCR and lateral flow tests. The former takes more than an hour to obtain results and the latter has difficulty detecting the virus at low concentrations (for cycling threshold values, CT values, >25 to 27). Therefore, the demand for a fast, cost-effective, and low detection limit testing method has been significantly increased. In this work, 60 human saliva samples with 30 positive and 30 negative were collected and tested with PCR for SARS-CoV-2 prior to using our disposable strips. For this technology, the test strip was connected to the gate electrode of the MOSFET on the printed circuit board that serves to amplify signals. A synchronous double-pulsed bias voltages (around 1 ms) were sent to both the drain and gate of the MOSFET. The resulting change in drain waveforms was converted to digital readings and compared with cycling threshold (Ct) values of human samples to assess this sensor technology. The result signifies that positive human samples with a range of Ct values from 17.8 to 40 can be differentiated, along with proving none of those high-risk organisms would hinder the sensitivity of our system. Which demonstrated the potential of this system to be developed into a cost-effective and point-of-care rapid detection for SARS-CoV-2. Figure 1

In this study, we present a double-layer NiO/β-Ga2O3 p-n heterojunction diode, which exhibits high performance with breakdown voltage, on-resistance and turn-on voltage. β-Ga2O3 has been attracting great attention as one of the excellent materials for next-generation high-performance electronics, owing to its high Baliga’s figure-of-merit (BFOM), carrier mobility, critical breakdown field strength and low-cost, simple growth methods. β-Ga2O3 based unipolar devices, especially Schottky barrier diodes, have been developed rapidly; however, the lack of p-type doping in Ga2O3 remains a challenge for bipolar devices, which can more generally be utilized in practical applications. One of the possible strategies is to introduce a p-type material to construct p-n junctions with n-type β-Ga2O3. The NiO turns out to be a feasible p-type material that has a wide bandgap, adjustable doping concentration, intrinsic p-type conductivity and diverse deposition techniques to form a uniform film, such as sputtering, PLD and thermal oxidation. In this study, we fabricated the diodes from depositing Ti/Au for the back Ohmic contact metal and annealing at 550℃ in N2, followed by sputtering two NiO layers with different doping concentrations by tuning the ratio of Ar/O2. The Ni/Au contact metal was deposited onto the NiO layer after annealing at 300℃ under O2 ambient. Compared to typical NiO thicknesses of 300 to 500 nm, we turned to another trend with ultra-thin layers of NiO. The top layer NiO thickness is 10nm while the bottom layer of NiO thickness varies from 10 to 80 nm. Through the design of the ultra-thin (20 nm) double-layer NiO structure, the breakdown voltage (Vb) is substantially improved to 4.7 kV and demonstrates the on-resistance (Ron) of 11.3 mΩ·cm2, which leads to a figure-of-merit (Vb 2/Ron) of 2 GW/cm2. The high Vb is attributed to the structure of both the double-layer and the guard-ring designs. From the TCAD simulation, the peak of the electric field locates at the edge of the diodes. Increasing the doping concentration of NiO layer contact with Ni/Au can reduce the electric field on the edge of the Ohmic contact. On the other hand, the low doping concentration of the NiO contact with β-Ga2O3 can effectively move the electric field crowding on the edge to the inside of devices. In addition, the extension guard ring can also spread the electric field crowding. This work provides a desirable design strategy for p-n heterojunction, which has the highest breakdown voltage among all Ga2O3-based p-n diodes. Figure 1

The analytical specificity and microbial interference of a SARS-CoV-2 biosensor detection platform were elucidated in this work. A cost-effective and highly sensitive detection system for the virus has been developed with the capability of producing quantitative results comparable with polymerase chain reaction (PCR) within 30 s. This could meet the demand for a fast diagnosis solution needed for the ongoing global pandemic. Disposable strips were biofunctionalized and immobilized with monoclonal SARS-CoV-2 antibodies. A printed circuit board embedded with a metal–oxide–semiconductor field-effect transistor (MOSFET) was also designed. The strips were connected to the gate electrode of the MOSFET, which received a synchronous pulse along with the drain electrode. The resulting waveform from the drain was then converted to digital readouts corresponding to virus or spike protein concentrations. We investigated 26 common organisms which are likely presented in the respiratory system along with 5 pathogens from the same genetic family of the SARS-CoV-2 virus for having cross-reaction or microbial interference, either of which would hinder the efficacy of the system. None of these organisms decreased the virus detection effectiveness of the sensor system.

The switching performance of unpackaged vertical geometry NiO/β-Ga2O3 rectifiers with a reverse breakdown voltage of 1.76 kV (0.1 cm diameter, 7.85 × 10−3 cm2 area) and an absolute forward current of 1.9 A fabricated on 20 μm thick epitaxial β-Ga2O3 drift layers and a double layer of NiO to optimize breakdown and contact resistance was measured with an inductive load test circuit. The Baliga figure-of-merit of the devices was 261 MW.cm−2, with differential on-state resistance of 11.86 mΩ.cm2. The recovery characteristics for these rectifiers switching from forward current of 1 A to reverse off-state voltage of −550 V showed a measurement-parasitic-limited recovery time (trr) of 101 ns, with a peak current value of 1.4 A for switching from 640 V. The reverse recovery time was limited by extrinsic parasitic and thus does not represent the intrinsic device characteristics. There was no significant dependence of trr on switching voltage or forward current.

Introduction The purpose of this study was to assess the effectiveness of the cable-plate-cable technique which comprises fixation of the proximal fragment using cable loops without additional proximal screws on the plate for the treatment of stable-stem periprosthetic femoral fractures around hip prostheses. Methods We retrospectively reviewed Vancouver types B1 and C periprosthetic femoral fractures treated with a dynamic compression plate combined with Dall-Miles cable between 2010 and 2016 at a single institution and followed for at least 12 months. Patients were treated with proximal fragment fixation using cable combined with screws (Group I) or with proximal fragment fixation using cable alone (Group II). Demographic data, fracture types, and clinical and radiological outcomes were analyzed. Results A total of 50 patients were included (Group I, n = 23 patients; Group II, n = 27). Fracture union was achieved in 49 patients with one case of non-union in Group I and no cases of non-union in Group II. Mean time to union was 5.4 months in Group I and 5.1 months in Group II (P = 0.624). Mean Harris hip score at latest assessment was 69.5 in Group I and 69.4 in Group II (P = 0.919). Regarding complications, there was one deep wound infection, one stem subsidence, and one loss of reduction in Group I, and one stem subsidence in Group II. No significant difference in clinical and radiological outcomes between groups was observed. Conclusions The cable-plate-cable technique sufficiently treats Vancouver types B1 and C periprosthetic femoral fractures without use of additional screws in the proximal fragment.

Purpose To describe an algorithm for arthroscopic reduction and minimally invasive surgery (ARMIS) and compare the surgical outcomes with standard open reduction–internal fixation (ORIF) for the treatment of supination–external rotation (SER) ankle fractures. Methods The inclusion criteria for this study were patients aged 16 years or older, the presence of a unilateral SER fracture, and injuries less than 2 weeks old. We retrospectively identified patients with SER fractures who underwent ORIF from January 2008 to December 2011 or ARMIS from January 2012 to December 2015. Data collected in December 2013 for the ORIF group and in December 2017 for the ARMIS group were compared. The algorithm for ARMIS was minimally invasive plating for lateral malleolar fractures first, followed by ankle arthroscopy for detection of syndesmotic injuries and then arthroscopic reduction of medial malleolar fractures or mini-open repair of the deltoid ligament. The talocrural angle, fibular length, tibiomedial malleolar angle, medial clear space, and tibiofibular clear space were measured radiographically. Functional evaluations included the visual analog scale pain score, American Orthopaedic Foot & Ankle Society ankle-hindfoot scales, and range of motion of bilateral ankles. Complications and reoperations were recorded for comparison. Results A total of 105 patients with SER fractures, 65 in the ARMIS group and 40 in the ORIF group, were included. Significantly lower incidences of complications (7.7% vs 27.5%, P = .006) and reoperations (1.5% vs 12.5%, P = .029) were found in the ARMIS group than in the ORIF group. More syndesmotic injuries were detected in the ARMIS group than in the ORIS group (80% vs 57.5%, P = .021). The visual analog scale pain score was significantly lower on day 3 postoperatively in the ARMIS group than in the ORIS group (1.96 ± 1.18 vs 2.83 ± 1.07, P = .027). The postoperative stay was shorter in the ARMIS group than in the ORIF group (3.66 ± 1.39 days vs 4.46 ± 2.23 days, P = .024). The operative time was longer in the ARMIS group than in the ORIS group (105.22 ± 27.13 minutes vs 93.59 ± 22.79 minutes, P = .038). A longer fluoroscopic time (0.43 ± 0.25 minutes vs 0.17 ± 0.07 minutes, P Conclusions Our algorithm and the ARMIS techniques may be a safe, reliable, and effective option in the treatment of SER fractures. ARMIS achieves promising surgical outcomes with less early postoperative pain, a shorter postoperative stay, and lower incidences of complications and reoperations compared with ORIF. However, the operative time is longer and the irradiation dose is higher with the ARMIS techniques. Level of Evidence Level III, retrospective comparative study.

Background We elucidated the effect of open reduction and internal fixation with locking plate for acute isolated displaced greater tuberosity fractures of humerus in elder adults (aged >60 years). Methods From 2009 to 2015, data from 32 patients, aged between 60 and 88 years, who had acute unilaterally displaced greater tuberosity fractures of humerus were collected and evaluated retrospectively. All the fractures were managed with open reduction and internal fixation with locking plate. The follow-up period was 50.8 months on an average (range 22-80 months). Finally, 25 patients were available for final evaluation of radiographic and functional results. Results All the 32 fractures had union with the average union time of 14 weeks (range 10-18 weeks) and with no complications. The average of preoperative Visual Analogue Scale (VAS) was 6.2 (range 4-8), ASES was 30.4 (range 13-45), and Constant score was 30.4 (range 20-45). At the last follow-up, the mean VAS was 1.3 (range 0-2.5), the mean ASES score was 90.1 (range 72-100), and the mean Constant score was 90.3 (range 80-100). There were statistically significant differences between preoperative and final follow-up in VAS, ASES, and Constant score. Hundred percent of patients had good or excellent results by Constant score, with excellent results (86-100) in 17 (68%) patients and good result (71-85) in 8 (32%). Conclusion In conclusion, open reduction and internal fixation with locking plate is an effective treatment for acute displaced greater tuberosity fractures of humerus in elder adults.

NiO is a promising alternative to p-GaN as a hole injection layer for normally-off lateral transistors or low on-resistance vertical heterojunction rectifiers. The valence band offsets of sputtered NiO on c-plane, vertical geometry homoepitaxial GaN structures were measured by x-ray photoelectron spectroscopy as a function of annealing temperatures to 600 °C. This allowed determination of the band alignment from the measured bandgap of NiO. This alignment was type II, staggered gap for both as-deposited and annealed samples. For as-deposited heterojunction, ΔEV = 2.89 eV and ΔEC = −2.39 eV, while for all the annealed samples, ΔEV values were in the range of 3.2–3.4 eV and ΔEC values were in the range of −(2.87–3.05) eV. The bandgap of NiO was reduced from 3.90 eV as-deposited to 3.72 eV after 600 °C annealing, which accounts for much of the absolute change in ΔEV − ΔEC. At least some of the spread in reported band offsets for the NiO/GaN system may arise from differences in their thermal history.

Vertical heterojunction NiO/β n-Ga2O/n+ Ga2O3 rectifiers employing NiO layer extension beyond the rectifying contact for edge termination exhibit breakdown voltages (VB) up to 4.7 kV with a power figure-of-merits, VB2/RON of 2 GW·cm−2, where RON is the on-state resistance (11.3 mΩ cm2). Conventional rectifiers fabricated on the same wafers without NiO showed VB values of 840 V and a power figure-of-merit of 0.11 GW cm−2. Optimization of the design of the two-layer NiO doping and thickness and also the extension beyond the rectifying contact by TCAD showed that the peak electric field at the edge of the rectifying contact could be significantly reduced. The leakage current density before breakdown was 144 mA/cm2, the forward current density was 0.8 kA/cm2 at 12 V, and the turn-on voltage was in the range of 2.2–2.4 V compared to 0.8 V without NiO. Transmission electron microscopy showed sharp interfaces between NiO and epitaxial Ga2O3 and a small amount of disorder from the sputtering process.

The band alignment of sputtered NiO on β-Ga2O3 was measured by x-ray photoelectron spectroscopy for post-deposition annealing temperatures up to 600 °C. The band alignment is type II, staggered gap in all cases, with the magnitude of the conduction and valence band offsets increasing monotonically with annealing temperature. For the as-deposited heterojunction, ΔE V = −0.9 eV and ΔE C = 0.2 eV, while after 600 °C annealing the corresponding values are ΔE V = −3.0 eV and ΔE C = 2.12 eV. The bandgap of the NiO was reduced from 3.90 eV as-deposited to 3.72 eV after 600 °C annealing, which accounts for most of the absolute change in ΔE V−ΔE C. Differences in thermal budget may be at least partially responsible for the large spread in band offsets reported in the literature for this heterojunction. Other reasons could include interfacial disorder and contamination. Differential charging, which could shift peaks by different amounts and could potentially be a large source of error, was not observed in our samples.

Our study provides references and guidelines, backed by evidence and real world data, in determining if and which certain surgical devices are more applicable to improve the outcome of unstable intertrochanteric fracture treatments. This retrospective case-crossover study compares the clinical and radiographic outcomes of 177 elderly patients from 2010 to 2014, who underwent procedures for unstable intertrochanteric fractures, specifically, AO/OTA type 31-A1.3 fractures using either the cephalic intramedullary device (Gamma3 IM nail system, Stryker®); or the fixation with sliding hip screws method (Dynamic Hip Screw, DHS, Synthes®). Clinical outcome conclusions were based on the union rates of the fractures during the patient’s one year follow-up. Radiographic conclusions were drawn from various factors, including neck shortening, neck-shaft angle, neck medialization, posterior tilting, callus formation time, Tip-apex distance (TAD), implant failure, and modified TAD, an additional factor further explained in the paper. The study shows evidence that the cephalic intramedullary device had significantly shorter union time, and significantly reduced rates of lag screw sliding and femoral shortening as well. No significant differences with regard to malunion and cut-out of the lag screw were found. The use of the intramedullary devices led to better clinical and radiographical outcomes for this specific fracture.

Sinus tarsi approach (STA) is the most commonly used minimally invasive surgery (MIS) in the treatment of displaced intra-articular calcaneal fracture (DIACF). However, there are some limitations related to its limited access. The goal of the present study is to describe a modified 2-incision STA and to evaluate the radiographic and clinical outcomes in the treatment of DIACF.Patients had a Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) classification 82-C, Sanders type II, III calcaneal fracture, and underwent modified 2-incision STA and internal fixation were included in this retrospective study. Serial radiographic measurements and clinical assessment were taken to evaluate the effectiveness of this technique.Thirty-four feet of 33 patients treated between 2014 and 2019 were included with an average follow-up of 28.5 (range, 12-65) months. Mean preoperative Böhler's angle was 1.5 ± 10.0 (range, -26.0-16.9) degrees and mean final Böhler's angle was 29.8 ± 4.9 (range, 19.3-39.3) degrees with significant difference (P.001). The average American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS) pain score at last follow-up were 86.2 ± 5.0 (range, 76-97) and 1.6 ± 1.1 (range, 0-4), respectively. Major complications included 2 (5.9%) wound infections and 1 (2.9%) incomplete separation of the lateral wall prior to plate insertion.This modified 2-incision STA is a safe and effective procedure. It allows access to the posterior facet and posterior calcaneal tuberosity, appropriate restoration of blowout lateral wall, and easy placement of a standard calcaneal plate.

Background Coronavirus disease 2019 (COVID-19) posed a major threat to the clinical practice of orthopedic surgeons, especially in the emergency department. We aim to present: (1) the criteria established by the Surgery Management Committee of Taipei Veterans General Hospital in response to COVID-19 and (2) the impact of COVID-19 screening on orthopedic trauma patients in the emergency department. Methods From April 1 to April 30, 2020, all orthopedic trauma patients in the emergency department were screened for COVID-19 if they fulfilled any of the following: (1) travel from abroad within 14 days, (2) high-risk occupation, (3) contact or cluster history with a COVID-19-positive patient, and (4) any associated symptom, including fever up to 38°C, cough, sore throat, rhinorrhea, loss of taste or smell, muscle soreness, malaise, or shortness of breath. We recorded details on the injury, fever, management, and associated outcomes. Results Of the 163 orthopedic trauma patients presenting to the emergency department, 24 were screened for COVID-19; of these, 22 received surgery. Sixty-two patients received surgery without screening for COVID-19. Fever was the most common reason to screen for COVID-19 (N = 20; 83.3%). No patients were COVID-19 positive. Screened patients had a significantly longer mean interval from presentation to the emergency department to surgery (2.7 ± 2.5 vs. 1.5 ± 0.8 days, p = 0.037). Of the 20 patients screened because of fever, the focus was not identified in 12 (60.0%) patients. The other eight had urinary tract infection (N = 6; 27.2%), septic hip (N = 1; 4.6%), and concomitant pneumonia and urinary tract infection (N = 1; 4.6%). The mean duration of fever and hospital stay was 4.3 ± 4.6 and 8.7 ± 4.9 days, respectively. There were no thromboembolic events, surgical complications, or in-hospital mortality. Conclusion We developed safe and reliable screening criteria for this COVID-19 pandemic. The delay in surgery was reasonable and did not adversely affect in-patient outcomes.

Background Bipolar hemiarthroplasty is a well-established treatment for displaced femoral neck fracture in elderly patients. Implant subsidence is a potential complication with cementless femoral stems, and smaller canal fill ratio has been reported as a radiographic risk factor. We aimed to determine the risk factors for subsidence, particularly the initial implant position relative to the resected medial calcar of proximal femur. Methods We retrospectively reviewed all cementless bipolar hemiarthroplasties performed using a single proximally hydroxyapatite-coated femoral stem in patients with a minimum radiographic follow-up of 12 weeks between January 2017 and December 2018. The amount of subsidence (significant subsidence defined as ≥ 5 mm), canal fill ratio, and implant position relative to the point of resected medial calcar (position A: medial and superior to calcar; position B: lateral and superior to calcar; position C: lateral and inferior to calcar) were measured and analyzed. Results One-hundred eighty patients were identified (mean age: 80.9 years). Significant subsidence was observed in 52 patients (28.9%). On multivariate analysis, older age, lower canal fill ratio, implant position B, C, and less medial overhang of stem were independent risk factors for early implant subsidence. The risk ratio of position B and C to position A was 5.13 (95% confidence interval, 2.23-11.80). Conclusion In our analysis, older age and lower canal fill ratio were associated with increased risk of subsidence, whereas implant with position A and more medial overhang were less prone to subsidence with the tapered proximally hydroxyapatite-coated implant.

An efficient technique was developed for the detection of human blood coagulation using a bio-microfluidic device based on Raman spectra [...]

Malalignment is the most important risk factor for fixation failure after intertrochanteric fracture treated with a cephalomedullay nail (CMN). Malalignment continues to occur despite advances in surgical techniques.We hypothesized that small femur canal size causes intra-operative reduction loss during cephalomedullary nail insertion.A retrospective study was performed from 2014 to 2017. Patients with acute intertrochanteric fracture implanted with the same sized CMN (Stryker, Mahwah, NJ, USA, diameter: 10mm, length: 170mm, degree 130) were included. Evaluated radiographic parameters included femoral canal size, corrected neck-shaft angle, and calcar reduction.The study totally included and analyzed the data from 108 patients. Patients with smaller femoral canal size tended to have increased calcar distance according to Pearson's correlation coefficient analysis (r(106)=-0.805, p0.001). Patients with calcar mal-reduction had higher corrected neck-shaft angle post-operatively. This observed correction tended to be lost during follow up.Small femoral canal size resulted in poorer reduction quality. Reduction loss during nail insertion may be due to the whole proximal fragment instead of the superolateral femoral neck. Reaming the isthmus before nail insertion or choosing a smaller sized CMN is indicated in this patient population to prevent intra- or post-operative loss of reduction.III; retrospective study.

Introduction This retrospective study aimed to report outcomes of fixation of bi-malleolar or tri-malleolar fractures combined with syndesmotic injury with or without posterior malleolar fracture (PMF), and to ascertain whether syndesmotic screw removal at 6 to 8 weeks or 3 months postoperatively is more beneficial. Methods We retrospectively reviewed patients who received open reduction and internal fixation for bi-malleolar (without PMF) or tri-malleolar ankle fracture (with PMF) with syndesmotic injury between January 2013 and December 2017 with at least 24 months of postoperative follow-up. All patients suffered syndesmotic instabilities and were treated using a syndesmotic screw without PMF fixation. Patients with bi-malleolar fracture with syndesmotic screw removal at 6 to 8 weeks postoperatively were included in Group I, tri-malleolar fracture with syndesmotic screw removal at 6 to 8 weeks in Group II, and tri-malleolar fracture with syndesmotic screw removal at 3 months in Group III. Demographic data, clinical and radiographic outcomes were analyzed. Results A total of 113 patients were included (Group I, n=47; Group II, n=43; Group III, n=23). Average size of PMF was 14% in patients with tri-malleolar fractures (Groups II and III). No significant difference in ankle functional outcome among groups was observed. The recurrence rate of syndesmotic instability was 10.6% in Group I, 20.9% in Group II, and 8.7% in Group III. Although the difference in recurrence rates of syndesmotic instability among three groups was not statistically significant (P=0.264), Group II showed more interval change in tibiofibular clear space between initial postoperative radiographs and last follow-up radiographs (P=0.028) compared to the other two groups. Fracture union was achieved in all patients without screw breakage. Conclusion We suggest that the better timing for syndesmotic screw removal is 3 months, instead of 6 to 8 weeks postoperatively, to reduce the risk of recurrence of syndesmotic instability for tri-malleolar fracture without posterior fragment fixation. Level of Evidence Level III- Case-control study.

BACKGROUND The trend of quick evolution and increased digital data in today’s operating rooms (ORs) has led to the construction of hybrid ORs. There is often a main control room with monitors for integrating intraoperative data from multiple devices in the hybrid OR. However, there is no adequate solution for communicating the data with people outside the OR. OBJECTIVE The objective of this study was to design an intelligent operating room (iOR) system, augmented onto the existing information technology (IT) infrastructure of hybrid ORs, to stream surgery performance and intraoperative imaging data. METHODS In this study, an all-in-one device with synergetic encoder and decoder was used. The device was able to stream multiple sources to one display. The lossless video and images from specific surgical workflows were streamed outside the hybrid OR through network protocols and were further managed by a streaming server and wireless control system. The steps of this study included the following: (1) defining the requirements and feasibility of an iOR system in the hybrid OR, (2) connecting multiple sources, (3) setting up equipment across the hybrid OR and a conference room, (4) designing a video management system, and (5) real-time streaming under specific surgical workflows. RESULTS The wired streamed video was shown simultaneously on the display in the hybrid OR and the display in the conference room with near-zero latency. Additionally, an interactive video between the hybrid OR and the conference room was achieved through the bidirectional wireless control system. The functions of recording, archiving, and playback were successfully provided by the streaming server. The readily available hardware components and open-access programming reduced the cost required to construct this streaming system. CONCLUSIONS This flexible and cost-effective iOR system not only provided educational benefits, but also contributed to surgical telementoring.

Background Treatment of displaced distal clavicular fractures is still controversial. This study reports the utility of a new coracoclavicular (CC) loop technique for acute displaced distal clavicular fractures and compared its surgical outcomes with those of the hook plate method. Methods In this retrospective study, a total of 23 patients with acute displaced distal clavicular fractures were treated with a new CC loop technique at a single institution from 2010 to 2014. Another group comprising 49 patients treated with a hook plate was compared with the CC loop group regarding clinical and radiologic outcomes. Results Seventy-two patients with at least 1 year of follow-up after both operations were included in this study. The Constant score was significantly greater in the CC loop group (95 vs 87, P = .009) at final follow-up. Moreover, the complication rate was significantly lower in the CC loop group (0% vs 24.5%, P = .007). The University of California, Los Angeles shoulder score and radiologic nonunion rate revealed no significant differences between the 2 groups. Conclusions The new CC loop technique had better clinical outcomes and lower complication rates compared with the hook plate technique.

Background Malalignment is the most important risk factor for fixation failure after intertrochanteric fracture treated with a cephalomedullay nail (CMN). Malalignment continues to occur despite advances in surgical techniques. Hypothesis We hypothesized that small femur canal size causes intra-operative reduction loss during cephalomedullary nail insertion. Methods A retrospective study was performed from 2014 to 2017. Patients with acute intertrochanteric fracture implanted with the same sized CMN (Stryker, Mahwah, NJ, USA, diameter: 10 mm, length: 170 mm, degree 130) were included. Evaluated radiographic parameters included femoral canal size, corrected neck-shaft angle, and calcar reduction. Results The study totally included and analyzed the data from 108 patients. Patients with smaller femoral canal size tended to have increased calcar distance according to Pearson's correlation coefficient analysis (r(106) = −0.805, p Conclusions Small femoral canal size resulted in poorer reduction quality. Reduction loss during nail insertion may be due to the whole proximal fragment instead of the superolateral femoral neck. Reaming the isthmus before nail insertion or choosing a smaller sized CMN is indicated in this patient population to prevent intra- or postoperative loss of reduction. Level of evidence III; retrospective study.

Background Radial height is an important prognostic factor in treating distal radius fracture. However, does further collapse of radial height in distal radius fractures after with volar locking plate fixation have a great impact on the prognosis? The present study aimed to elucidate radial height loss and determine the associated risk factors after open reduction and internal fixation with volar locking plate in patients with extra-articular distal radius fractures. Hypothesis Patients with radial height collapse after fracture reduction and internal fixation with a volar locking plate may have poor outcomes. Methods Data of 87 patients (21 male) undergoing surgery for acute extra-articular distal radius fractures (AO: 23-A2 or 23-A3) between February 2014 and July 2016 were evaluated retrospectively. Patients were divided into two groups by radial height loss. Potential risk factors were tested by Pearson correlation coefficients. Stepwise multiple regression logistic analysis determined significant independent risk factors for extra-articular distal radius fractures. Clinical evaluation was performed by the same surgeon by determining wrist ROM. Grip strength was measured with a Jamar dynamometer and compared with non-affect wrist in percentage. In addition, all the patients were asked to grade modified Mayo wrist score and Visual Analogue Scale (VAS) score. These findings were recorded post-operative 1 year of follow up. Results Mean radial height loss was 1.3 ± 0.9 mm. Age (s = 0.002, p = 0.003), postoperative ulnar-positive deformity (s = 0.107, p Discussion Radial height loss is noted in patients undergoing open reduction and internal fixation with volar locking plate for extra-articular distal radius fractures. Risk factors for radial height collapse include advanced age, poor bone quality, shortest distance between fracture site and articular surface and post-operative ulnar-positive deformity. Level of evidence IV; non-comparative prospective study.

Radial height is an important prognostic factor in treating distal radius fracture. However, does further collapse of radial height in distal radius fractures after with volar locking plate fixation have a great impact on the prognosis? The present study aimed to elucidate radial height loss and determine the associated risk factors after open reduction and internal fixation with volar locking plate in patients with extra-articular distal radius fractures.Patients with radial height collapse after fracture reduction and internal fixation with a volar locking plate may have poor outcomes.Data of 87 patients (21 male) undergoing surgery for acute extra-articular distal radius fractures (AO: 23-A2 or 23-A3) between February 2014 and July 2016 were evaluated retrospectively. Patients were divided into two groups by radial height loss. Potential risk factors were tested by Pearson correlation coefficients. Stepwise multiple regression logistic analysis determined significant independent risk factors for extra-articular distal radius fractures. Clinical evaluation was performed by the same surgeon by determining wrist ROM. Grip strength was measured with a Jamar dynamometer and compared with non-affect wrist in percentage. In addition, all the patients were asked to grade modified Mayo wrist score and Visual Analogue Scale (VAS) score. These findings were recorded postoperative 1 year of follow-up.Mean radial height loss was 1.3±0.9mm. Age (ß=0.002, p=0.003), postoperative ulnar-positive deformity (ß=0.107, p0.001), DEXA (ß=-0.015, p=0.008), and shortest diameter of distal fracture fragment in AP and lateral views (ß=-0.050, p=0.037; ß=-0.080, p=0.043) were significantly associated with radial height loss. As for the outcome of clinical prognosis, though radial height collapse group had poorer wrist range of motion, there was no statistical difference. Besides, there were no significant differences in grips strength and VAS score between these two groups. However, in regards of modified Mayo wrist score, the percentage of patients with poor outcomes is significant higher in radial height collapse group (p=0.039). Moreover, all patients with poor outcomes in radial height collapse groups were older than 65-year-old.Radial height loss is noted in patients undergoing open reduction and internal fixation with volar locking plate for extra-articular distal radius fractures. Risk factors for radial height collapse include advanced age, poor bone quality, shortest distance between fracture site and articular surface and postoperative ulnar-positive deformity.IV; non-comparative prospective study.

Open reduction and internal fixation (ORIF) with plate is the standard treatment for displaced intra-articular calcaneal fractures. We constructed a three-dimensional complete foot finite element model, which was also modified to evaluate the biomechanical effect of Sanders IIB tongue-type calcaneal fracture treated by ORIF with locking plate. We compared plates with locking screws (LSs) and those with non-locking screws (NSs). Static standing was simulated by applying ground reaction force and the pulling force of the Achilles tendon. ORIF with plate using NS or LS provided good stability for Sanders IIB tongue-type calcaneal fracture and might allow light touch weight-bearing in the early postoperative period.

Background Infected nonunion of the femoral shaft is uncommon, and usually presents with challenging therapeutic and reconstructive problems. There are still controversies over treating infected nonunion of the femoral shaft. The purposes of this retrospective study were to review the treatment outcomes and describe a staged protocol for spontaneous wound healing. Methods Six patients with chronic femoral shaft infected-nonunion from October 2002 to September 2010 were included in this retrospective study. Serial plain films and triple films of lower legs were performed to evaluate the alignment of the treated femoral shaft and bony union following our staged protocol of Ilizarov distraction osteogenesis and intramedullary nailing. Results An average bone defect of 7 cm was noted after staged osteotomy. Mean follow-up was 87.5 (range, 38–133) months. Union was achieved in all six patients, with an average external fixation time of 6.8 (range, 5–11) months. There was no reinfection. One complication of a 4-cm leg discrepancy was noted, with an initial shortening of 15 cm. The mean knee ranges of motion (ROM) before staged protocols and at final follow-up were 64.2 ± 8.6 (range, 60–75)° and 53.3 ± 9.3 (range, 40–65)°, respectively. The ROM at the knee joint statistically decreased following staged protocols. Conclusion In the treatment of chronic femur osteomyelitis, the staged protocol of Ilizarov distraction osteogenesis followed by intramedullary nailing was safe and successful, and allowed for union, realignment, reorientation, and leg-length restoration. With regard to the soft tissue, this technique provides a unique type of reconstructive closure for infected wounds. It is suggested that the staged protocol is reliable in providing successful simultaneous reconstruction for bone and soft tissue defects without flap coverage.