Effects of vertical compression during pediatric cardiopulmonary resuscitation using the one-handed chest compression technique.

OBJECTIVE: The posture of the rescuer while performing the one-handed chest compression (OHCC) has not yet been evaluated. This study aimed to investigate the effect of vertical compression during pediatric cardiopulmonary resuscitation (CPR) using the OHCC technique. METHODS: This was a prospective randomized crossover simulation trial. A total of 42 medical doctors conducted a 2-min single-rescuer CPR using the conventional OHCC (Test 1) or vertical OHCC (Test 2) technique on a pediatric manikin. The chest compression and ventilation parameters were measured in real time during the experiments using sensors embedded in the manikin. In addition, the compression force of each technique was measured using a force plate. RESULTS: The average and adequate chest compression depth (CCD) were significantly higher in Test 2 than in Test 1 (average depth: 54.0 mm (interquartile range [IQR]: 48.5-56.0) in Test 2 vs. 49.0 mm (IQR: 40.0-54.0) in Test 1, P < 0.001; adequate depth: 99.0% (IQR: 36.3-100.0) in Test 2 vs. 52.0% (IQR: 0.0-98.0) in Test 1, P < 0.001). The average force of compression was also significantly higher in vertical OHCC than that in conventional OHCC (25.7 kg ± 4.4 in vertical OHCC vs. 24.5 kg ± 4.2 in conventional OHCC, P < 0.001). The ventilation parameters were not significantly different between Tests 1 and 2. CONCLUSIONS: The vertical OHCC could provide a deeper and more adequate CCD compared with the conventional OHCC, and the advantages of the vertical OHCC originate from the superiority of the compression force.

Dynamic Ultrasonographic Measurement of Inferior Joint Capsule Thickness in Patients with Unilateral Frozen Shoulder.

The diagnostic value of ultrasonography (US) for frozen shoulder (FS) is not well established. This study aimed to assess the diagnostic value of US measurement of inferior joint capsule (IJC) thickness and evaluate changes in the thickness of the IJC by US depending on arm position. A total of 71 patients with clinically diagnosed unilateral FS who underwent bilateral US measurement of the IJC were enrolled in this study. The US measurement of the IJC was performed with a linear transducer positioned around the anterior axillary line with the shoulder 40° abducted and with neutral rotation of the glenohumeral joint (neutral position). We also measured the IJC thickness in the externally rotated and internally rotated positions with the shoulder 40° abducted. In the neutral position, as well as in the internally rotated and externally rotated positions, the thickness of the IJC on US was significantly higher in the affected shoulder than that in the unaffected shoulder (all p < 0.001). On both the affected and unaffected sides, the US thickness of the IJC in the neutral position was significantly higher than that in the externally rotated position (p < 0.001), but lower than that in the internally rotated position (p < 0.001). Regarding IJC thickness in the neutral position, a 3.2-mm cutoff value yielded the highest diagnostic accuracy for FS, with a sensitivity and specificity of 73.2% and 77.5%, respectively. The area under the curve for IJC thickness was 0.824 (95% confidence interval, 0.76-0.89). US measurement of the IJC in the neutral position yielded good diagnostic accuracy for FS. Because IJC thickness is affected by arm rotation, it is important to measure the IJC thickness in a standardized posture to ensure diagnostic value.

Intraneural ganglion cyst of the lumbosacral plexus mimicking L5 radiculopathy: A case report.

BACKGROUND: Intraneural ganglion cysts are benign gelatinous masses that form within the epineurium of a peripheral nerve. Only few cases of intraneural ganglion cyst arising from the hip joint have been reported. CASE SUMMARY: A previously healthy 65-year-old woman who had been experiencing left buttock pain radiating to the dorsum of the foot for 2 years visited our clinic. Prior to visiting the clinic, she underwent lumbar spine magnetic resonance imaging and received physiotherapy, pain killers, and epidural injections based on a presumptive diagnosis of spinal stenosis for 2 years in other hospitals. Repeat magnetic resonance imaging revealed joint connection of the articular branch of the hip joint and rostral extension of the cyst along the L5 spinal nerve near the L5-S1 neural foramen. The patient was diagnosed with intraneural ganglion cyst arising from the articular branch of the hip joint based on high-resolution magnetic resonance neurography. Using the arthroscopic approach, a cystic opening within the intra-articular space was detected, and cyst decompression was then performed. The pain in the left leg was significantly relieved during the 6-mo follow-up. CONCLUSION: Although intraneural ganglion cysts arising from the hip joint are rare, they can cause typical radicular pain and mimic common L5 radiculopathy. Typical cyst ascent phenomenon starting from the termination of the articular branch on magnetic resonance imaging is a crucial finding indicative of intraneural ganglion cysts arising from the hip joint.

Severe Cutaneous Adverse Reactions to Antiepileptic Drugs: A Nationwide Registry-Based Study in Korea.

PURPOSE: Severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS) to antiepileptic drug (AED), are rare, but result in significant morbidity and mortality. We investigated the major culprit drugs, clinical characteristics, and clinical course and outcomes of AED-induced SCARs using a nationwide registry in Korea. METHODS: A total of 161 patients with AED-induced SCARs from 28 referral hospitals were analyzed. The causative AEDs, clinical characteristics, organ involvements, details of treatment, and outcomes were evaluated. We compared the clinical and laboratory parameters between SJS/TEN and DRESS according to the leading causative drugs. We further determined risk factors for prolonged hospitalization in AED-induced SCARs. RESULTS: Carbamazepine and lamotrigine were the most common culprit drugs causing SCARs. Valproic acid and levetiracetam also emerged as the major causative agents. The disease duration and hospital stay in carbamazepine-induced SJS/TEN were shorter than those in other AEDs (P< 0.05, respectively). In younger patients, lamotrigine caused higher incidences of DRESS than other drugs (P= 0.045). Carbamazepine, the most common culprit drug for SCARs, was associated with a favorable outcome related with prolonged hospitalization in SJS (odds ratio, 0.12; 95% confidence interval, 0.02-0.63, P= 0.12), and thrombocytopenia was found to be a risk factor for prolonged hospitalization in DRESS. CONCLUSION: This was the first large-scale epidemiological study of AED-induced SCARs in Korea. Valproic acid and levetiracetam were the significant emerging AEDs causing SCARs in addition to the well-known offending AEDs such as carbamazepine and lamotrigine. Carbamazepine was associated with reduced hospitalization, but thrombocytopenia was a risk factor for prolonged hospitalization. Our results suggest that the clinical characteristics and clinical courses of AED-induced SCARs might vary according to the individual AEDs.

Effects of Grain Size on the Electrical Characteristics of Three-Dimensional NAND Flash Memory Devices.

Polysilicon is commonly used as the channel in three-dimensional (3D) NAND flash memory devices. However, degradation of device performance due to grain boundary traps in the channel is a major issue. The saturation on-current level, threshold voltage (Vth), and electron density of 3D NAND flash memory devices with randomly generated grain boundaries were investigated by using three-dimensional technology computer-aided design (TCAD) simulation. The device performance tended to degrade with an increasing number of grains, and the direction of the grains significantly affected the device performance. The large decrease in the electron density of the channel region due to the direction of the grains can be explained according to the formation of the depletion region.

Phenotypes of Severe Cutaneous Adverse Reactions Caused by Nonsteroidal Anti-inflammatory Drugs.

PURPOSE: Nonsteroidal anti-inflammatory drugs (NSAIDs) are common cause of severe cutaneous adverse reactions (SCARs). The present study aimed to investigate the characteristics of SCARs induced by NSAIDs in the Korean SCAR registry. METHODS: A retrospective survey of NSAID-induced SCARs recorded between 2010 and 2015 at 27 university hospitals in Korea was conducted. Clinical phenotypes of SCARs were classified into Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), SJS-TEN overlap syndrome and drug reaction with eosinophilia and systemic symptoms (DRESS). Causative NSAIDs were classified into 7 groups according to their chemical properties: acetaminophen, and propionic, acetic, salicylic, fenamic and enolic acids. RESULTS: A total of 170 SCARs, consisting of 85 SJS, 32 TEN, 17 SJS-TEN overlap syndrome and 36 DRESS reactions, were induced by NSAIDs: propionic acids (n=68), acetaminophen (n=38), acetic acids (n=23), salicylic acids (n=16), coxibs (n=8), fenamic acids (n=7), enolic acids (n=5) and unclassified (n=5). Acetic acids (22%) and coxibs (14%) accounted for higher portions of DRESS than other SCARs. The phenotypes of SCARs induced by both propionic and salicylic acids were similar (SJS, TEN and DRESS, in order). Acetaminophen was primarily associated with SJS (27%) and was less involved in TEN (10%). DRESS occurred more readily among subjects experiencing coxib-induced SCARs than other NSAID-induced SCARs (62.5% vs. 19.7%, P = 0.013). The mean time to symptom onset was longer in DRESS than in SJS or TEN (19.1 ± 4.1 vs. 6.8 ±1.5 vs. 12.1 ± 3.8 days). SCARs caused by propionic salicylic acids showed longer latency, whereas acetaminophen- and acetic acid-induced SCARs appeared within shorter intervals. CONCLUSIONS: The present study indicates that the phenotypes of SCARs may differ according to the chemical classifications of NSAIDs. To establish the mechanisms and incidences of NSAID-induced SCARs, further prospective studies are needed.

Effects of the Grain Boundary and Interface Traps on the Electrical Characteristics of 3D NAND Flash Memory Devices.

Three-dimensional (3D) NAND flash memory devices having a poly-silicon channel with grain boundaries, the cylindrical macaroni channel being outside the inter-oxide filler layer and inside the tunneling oxide layer, were evaluated. The effects of the grain size, grain boundary trap density, and interface trap density at the interfaces between the channel and the oxide layers on the electrical characteristics of 3D NAND flash memory devices were investigated. The electron density of the channel was changed depending on the grain boundary trap density and the position of the grain boundary trap in the channel. The grain boundary traps increased the potential barrier and decreased the electron density of the channel. The threshold voltage increased with increasing grain boundary trap density and interface trap density.

The effect of humeral tunnel locations on radiographic tunnel changes in baseball players following medial ulnar collateral ligament reconstruction: comparison of anatomic and nonanatomic locations.

BACKGROUND: There has been no study on radiologic changes after medial ulnar collateral ligament (MUCL) reconstruction and related clinical features. METHODS: Data from 39 baseball players who underwent MUCL reconstruction were collected and analyzed. The baseball players were classified into 2 groups according to the starting point of the humeral tunnel: (1) the lower tip of the medial epicondyle (group NA, n = 21) and (2) the remnant of the MUCL (group A, n = 18). Bone tunnel characteristics and changes were evaluated by computed tomography (CT) at 3 and 9 months postoperatively. Outcome measures consisted of the visual analog scale, range of motion (ROM), the Conway scale, and the presence of ulnar nerve irritation postoperatively. RESULTS: The mean diameter of the humeral entry was 4.0 mm (range, 3.4-5.1 mm) on the first CT scan, which increased to 5.5 mm (range, 3.2-7.2 mm) on the follow-up CT scan (P < .001). The mean diameter of the ulnar tunnel was 2.8 mm (range, 1.1-3.3 mm) on the first CT scan, which decreased to 1.6 mm (range, 0-4.3 mm) on the follow-up CT scan (P < .001). The between-group comparison revealed no differences in the changes in the diameter of the humeral and ulnar tunnels. A statistically significant correlation was not found between athletic performance measured by the Conway scale and the radiologic changes on CT evaluation (P = .182). Group A showed improvement in extension from 7° preoperatively to 1° postoperatively (P < .001) and in flexion from 126° preoperatively to 136° postoperatively (P < .001), while group NA did not achieve statistical significance in ROM improvement after the operation. CONCLUSIONS: Humeral tunnel widening was commonly observed, while the ulnar tunnel was maintained or became narrowed conversely. The humeral tunnel placements did not affect tunnel changes after the surgical procedure; however, MUCL reconstruction with the anatomic location of the humeral tunnel yielded substantial improvement in elbow ROM.

Efficiency Enhancement in Polymer Light-Emitting Devices Fabricated Utilizing a MoO3 Hole Injection Layer Coated with Different Solvents.

Polymer light-emitting devices (PLEDs) with a MoO3 hole injection layer (HIL) were fabricated to enhance their luminance efficiency. Ultraviolet photoelectron spectroscopy spectra showed that the valence band maximum level of the MoO3 layer was located between the work function of the the indium-tin-oxide anode and the highest occupied molecular orbital level of the poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] hole transport layer. The surface of the MoO3 layer formed by using an ethanol solvent was smoother than that of the MoO layer formed by using a deionized water solvent due to a decrease in the aggregation of the MoO3 resolved in ethanol. The MO3 HIL decreased the operating voltage of the PLED and increased the luminance and the luminance efficiency of the PLED due to a decrease in the hole injection barrier. The operating voltage, the luminance, and the luminance efficiency of the PLEDs with the MoO3 HIL formed by using an ethanol solvent were enhanced in comparison with those of the PLEDs with a MoO3 HIL formed by using a deionized water solvent due to a decrease in the surface roughness of the HIL.

Transparent Conducting Silver-Nanowire-Embedded Poly(methyl methacrylate) Nanocomposite Films Formed by Using a Transfer Method.

Poly(methyl methacrylate) (PMMA) substrates containing silver nanowires (Ag NWs) were fabricated by using a transfer method. Ag NWs with a length of 20 µm and a width of 80 nm were synthesized by using a modified polyol process. Ag NW electrodes with a high surface roughness value on glass substrates were significantly improved by using both a transfer method and a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate layer coating. The peak-to-valley roughness of the Ag NWs decreased from 210 to 26 nm resulting from the filling of the PMMA into the vacancies among the Ag NWs, and the corresponding root-mean-square roughness decreased from 74 to 6 nm. Atomic force microscopy images showed a dramatic decrease in the surface roughness of the PMMA substrates containing Ag NWs. The optical transmittance and the sheet resistance of the optimized Ag NW-embedded PMMA substrates were 80% and 14 Ω/sq, respectively.

Clinical and radiological outcomes of type 2 superior labral anterior posterior repairs in elite overhead athletes.

BACKGROUND: Although there are multiple reports on surgical outcomes of type 2 superior labral anterior posterior (SLAP) repairs, a literature review noted a paucity of data on clinical and radiological outcomes in elite overhead athletes. PURPOSE: To determine midterm clinical outcomes of type 2 SLAP repairs in elite overhead athletes and whether labral integrity provides consistent return to play. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Medical records were retrospectively reviewed of 24 elite overhead athletes who underwent arthroscopic type 2 SLAP repairs. There were 18 men and 6 women, and their mean age was 22.7 years (range, 19-30 years); the majority of them (16/24) were baseball players. Four outcome measures were used: visual analog scale (VAS) for pain and satisfaction, American Shoulder and Elbow Surgeons (ASES) score, subjective feeling of recovery, and return to play. Multidetector computed tomographic arthrography was performed to evaluate labral integrity after surgery. RESULTS: At a mean follow-up of 45.8 months (range, 24-68 months), overall pain and function improved significantly. The VAS for pain was 5.7 preoperatively and 2.0 postoperatively (P < .01), and VAS for satisfaction was 8.6. The ASES score was 55.8 preoperatively and 87.1 postoperatively (P < .01). The overall mean value of subjective feeling of recovery was approximately 76%. Twelve of 24 athletes (50%) returned to play after the operation. Although there was a trend toward higher return rate in the other overhead athletes (75%) compared with the baseball players (38%), this trend did not reach statistical significance (P = .097). Labral retear with clinical significance was noted in 2 athletes who failed to return to play. Osteolysis was observed in 2 athletes, 1 of whom had a retear. A statistical relation between the integrity of the repair and return to play was not found (P > .05). CONCLUSION: Arthroscopic SLAP repairs show favorable clinical and radiological outcomes; however, the study findings raise a concern that return to play may still be problematic in elite baseball players. This study also indicates that labral healing does not ensure consistent return to play in elite overhead athletes.

Case report: Thoracic outlet syndrome in an elite archer in full-draw position.

BACKGROUND: One possible pathomechanism of thoracic outlet syndrome (TOS) is shoulder abduction and extension inducing backward motion of the clavicle which causes compression on the brachial plexus. This position occurs during the full-draw stage of archery, by drawing and holding the bowstring. CASE DESCRIPTION: A 28-year-old elite archer presented with a feeling of weakness and dull shoulder pain, and experienced decreased grip power and hypoesthesia in the ulnar nerve dermatome in the full-draw position. On CT angiography, the cross-sectional area of the subclavian artery in the costoclavicular space decreased to 40% compared with that of the subclavian artery in a noncompressed state. This patient had first rib resection through the supraclavicular approach with a clavicle osteotomy. At 3.5 years postoperatively, the patient maintained his job as a professional coach and did not have any specific complaints when teaching and demonstrating archery skills. LITERATURE REVIEW: A literature review revealed numerous causes of TOS, ranging from congenital abnormalities to repetitive postures related to sports activities. The abduction and external rotation (ABER) position (shoulder at 90° abduction and external rotation) has been suggested for detecting TOS and is a documented cause of compression of the brachial plexus and subclavian vessels. We present the case of an archer with TOS association with repeated use of the ABER position. PURPOSE AND CLINICAL RELEVANCE: TOS should be suspected when athletes repeatedly use shoulder extension and abduction for their sports if other pathologic conditions can be ruled out.