Passive wing deployment and retraction in beetles and flapping microrobots.

Birds, bats and many insects can tuck their wings against their bodies when at rest and deploy them to power flight. Whereas birds and bats use well-developed pectoral and wing muscles1,2, how insects control their wing deployment and retraction remains unclear because this varies among insect species. Beetles (Coleoptera) display one of the most complex mechanisms. In rhinoceros beetles, Allomyrina dichotoma, wing deployment is initiated by complete release of the elytra and partial release of the hindwings at their bases. Subsequently, the beetle starts flapping, elevates the hindwing bases and unfolds the hindwing tips in an origami-like fashion. Although the origami-like fold has been extensively explored3-8, limited attention has been given to the hindwing base movements, which are believed to be driven by the thoracic muscles5,9-11. Here we demonstrate that rhinoceros beetles can effortlessly deploy their hindwings without necessitating muscular activity. We show that opening the elytra triggers a spring-like partial release of the hindwings from the body, allowing the clearance needed for the subsequent flapping motion that brings the hindwings into the flight position. After flight, the beetle can use the elytra to push the hindwings back into the resting position, further strengthening the hypothesis of passive deployment. We validated the hypothesis using a flapping microrobot that passively deployed its wings for stable, controlled flight and retracted them neatly upon landing, demonstrating a simple, yet effective, approach to the design of insect-like flying micromachines.

Tibial-sided Anterolateral Ligament Injuries Are Associated With Poor Healing and Residual Pivot Shift Testing After Anterior Cruciate Ligament Reconstruction.

PURPOSE: To investigate whether tibial-sided anterolateral ligament (ALL) injuries are associated with poor healing and residual pivot shift. METHODS: Patients who underwent anterior cruciate ligament reconstructions within postinjury 6 weeks from January 2008 to March 2021 were included. They had concomitant ALL injury confirmed by preoperative magnetic resonance imaging (MRI) and were followed for a minimum of 20 months. Preoperative ALL injury was graded by the Muramatsu classification, and postoperative ALL healing were graded by a modification of the Lee classification (good, partial, and nonvisualized). The patients were allocated to an improved group (IG) and an unimproved group (UG) on the basis of a comparison of pre- and postoperative MRI. ALL tear site, postoperative knee stability, Lysholm score, and Tegner activity scale (patient-reported outcomes [PROs]) were compared between the 2 groups. RESULTS: In total, 128 patients were enrolled; 94.5% patients achieved the minimal clinically important difference for PROs, respectively. The ALL was torn at the femoral side in 46.9% patients, at midsubstance in 31.2.%, and at tibial side in 21.9%, Preoperatively, 86 (67.2%) patients had a partial tear, and 42 (32.8%) patients had a complete tear. On the basis of the postoperative MRI appearances, 38 (29.7%) and 90 (70.3%) patients were allocated to the IG and UG, respectively. The tibial-side tears were significantly frequent in the UG (P = .032). Pivot shift showed a significantly greater incidence in the UG than IG (P = .004). Lachman test and PROs did not differ between the 2 groups. CONCLUSIONS: Tibial-sided ALL tears occurred in 18.7% of the UG compared with 3.2% of the IG, and 45.6% of the UG had a postoperative grade 1 or 2 pivot shift compared with 15.8% of the IG. Percentages of patients with the minimal clinically important difference for PROs did not differ between the 2 groups. However, the clinical relevance is limited by a high transfer bias. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Effect of Solitary Osteochondroma on Alignment and Length in the Lower Extremities.

BACKGROUND: There is a lack of information about the effects of untreated solitary osteochondroma (SO) on longitudinal growth of the lower extremities in children and adolescents. This study aimed to assess the coronal alignment and length of the lower extremity in patients with SO around the knee and to identify the factors related to the development of deformities. METHODS: We retrospectively reviewed 111 patients diagnosed with SO around the knee. The patients were classified into 2 groups depending on the location of the SO: 51 in the distal femur and 60 in the proximal tibia. Characteristics of the lesions, such as type, location, size, and distance from the joint line, were determined. Radiographic analysis of the lower limbs included mechanical lateral distal femoral angle, mechanical medial proximal tibial angle, whole-leg length, femoral length, and tibial length. RESULTS: The mean age at the time of diagnosis was 12.3±3.4 years. No statistically significant differences were found between the affected and contralateral sides for mechanical lateral distal femoral angle and mechanical medial proximal tibial angle in either the distal femur or the proximal tibia groups. In patients with femoral lesions, the femoral and whole-leg lengths were significantly shorter on the affected side than on the unaffected side ( P <0.001 and 0.002, respectively), and the mean differences were 2.1±3.6 and 2.1±4.4 mm, respectively. Univariate logistic regression analysis did not reveal any factors associated with limb length discrepancy (LLD). In patients with tibial lesions, no statistically significant differences were found in LLD. CONCLUSIONS: SOs around the knee did not cause clinically significant deformity of the lower extremity. However, in contrast to proximal tibia lesions, SO in the distal femur was associated with the shortening of the affected limb. Consideration should be given to the development of LLD in skeletally immature children with SO in the distal femur. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Surgical management of severe planovalgus foot deformity in children with generalised joint hypermobility.

BACKGROUND: This study aimed to evaluate the outcomes of calcaneal lengthening osteotomy (CLO) and double arthrodesis of the talonavicular and calcaneocuboid joints (DA) for correcting planovalgus foot deformity exclusively in patients with generalised joint hypermobility. METHODS: We retrospectively reviewed 29 feet in 17 consecutive patients who underwent either CLO or DA. The mean age at surgery was 11.3 ± 2.3 years, and the mean follow-up duration was 7.7 ± 3.2 years. Preoperative and final follow-up radiographs and dynamic foot-pressure measurements were analysed. RESULTS: Both operations significantly improved the radiographic parameters, except for the lateral talocalcaneal angle in the CLO group. Pedobarographic study demonstrated an elevation of the medial longitudinal arch and an improved foot-pressure distribution after both surgeries. The plantar pressure in the lateral forefoot significantly increased only in the DA group, while the pressures exerted on the medial forefoot and hindfoot and the arch index improved only in the CLO group. CONCLUSIONS: Both CLO and DA effectively improve the foot alignments of the deformity in patients with generalised joint hypermobility. However, differences were observed in the changes in the lateral talocalcaneal angle and plantar pressure distribution between the two procedures. LEVEL OF EVIDENCE: Therapeutic Level III.

Modeling of Fabry disease nephropathy using patient derived human induced pluripotent stem cells and kidney organoid system.

OBJECTIVES: To explore the possibility of kidney organoids generated using patient derived human induced pluripotent stem cells (hiPSC) for modeling of Fabry disease nephropathy (FDN). METHODS: First, we generated hiPSC line using peripheral blood mononuclear cells (PBMCs) from two male FD-patients with different types of GLA mutation: a classic type mutation (CMC-Fb-001) and a non-classic type (CMC-Fb-003) mutation. Second, we generated kidney organoids using wild-type (WT) hiPSC (WTC-11) and mutant hiPSCs (CMC-Fb-001 and CMC-Fb-003). We then compared alpha-galactosidase A (α-GalA) activity, deposition of globotriaosylceremide (Gb-3), and zebra body formation under electromicroscopy (EM). RESULTS: Both FD patients derived hiPSCs had the same mutations as those detected in PBMCs of patients, showing typical pluripotency markers, normal karyotyping, and successful tri-lineage differentiation. Kidney organoids generated using WT-hiPSC and both FD patients derived hiPSCs expressed typical nephron markers without structural deformity. Activity of α-GalA was decreased and deposition of Gb-3 was increased in FD patients derived hiPSCs and kidney organoids in comparison with WT, with such changes being far more significant in CMC-Fb-001 than in CMC-Fb-003. In EM finding, multi-lammelated inclusion body was detected in both CMC-Fb-001 and CMC-Fb-003 kidney organoids, but not in WT. CONCLUSIONS: Kidney organoids generated using hiPSCs from male FD patients might recapitulate the disease phenotype and represent the severity of FD according to the GLA mutation type.

Bone Mineral Density and the Risk of Parkinson's Disease in Postmenopausal Women.

BACKGROUND: Whether bone mineral density (BMD) is related to the risk of Parkinson's disease (PD) is unclear. OBJECTIVES: The objective of this study was to examine the association between BMD status and incident PD in postmenopausal women. METHODS: We retrospectively examined a nationwide cohort of 272,604 women aged 66 years who participated in the 2009-2012 Korean national health screening for transitional ages. BMD was evaluated using dual-energy X-ray absorptiometry of the central bones. The use of antiosteoporosis medications (AOMs) was assessed. We performed multivariable Cox proportional hazards regression to evaluate the association between BMD and PD risk by calculating hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During the median follow-up of 7.7 years, 2,884 (1.1%) incident PD cases developed. After adjusting for confounding factors, lower BMD was associated with an increased risk of PD (P for trend <0.001). Individuals with osteoporosis had a 1.40-fold higher HR (1.40, 95% CI: 1.25-1.56) than those with a normal BMD. Sensitivity analyses suggested the associations robust to longer lag periods and further adjustment. These associations were prominent in individuals without AOM use before or after enrollment (P for interaction = 0.031 and 0.014). Increased risks of PD in individuals with osteopenia and osteoporosis who did not use AOMs were attenuated by the medication use during the follow-up period, regardless of previous AOM use. CONCLUSIONS: Lower postmenopausal BMD and osteoporosis were associated with an increased risk of PD. In addition, this association could be mitigated using AOMs. Proper management of BMD in postmenopausal women may help prevent PD. © 2023 International Parkinson and Movement Disorder Society.

Prediction of intradialytic hypotension using pre-dialysis features-a deep learning-based artificial intelligence model.

BACKGROUND: Intradialytic hypotension (IDH) is a serious complication of hemodialysis (HD) that is associated with increased risks of cardiovascular morbidity and mortality. However, its accurate prediction remains a clinical challenge. The aim of this study was to develop a deep learning-based artificial intelligence (AI) model to predict IDH using pre-dialysis features. METHODS: Data from 2007 patients with 943 220 HD sessions at seven university hospitals were used. The performance of the deep learning model was compared with three machine learning models (logistic regression, random forest and XGBoost). RESULTS: IDH occurred in 5.39% of all studied HD sessions. A lower pre-dialysis blood pressure (BP), and a higher ultrafiltration (UF) target rate and interdialytic weight gain in IDH sessions compared with non-IDH sessions, and the occurrence of IDH in previous sessions was more frequent among IDH sessions compared with non-IDH sessions. Matthews correlation coefficient and macro-averaged F1 score were used to evaluate both positive and negative prediction performances. Both values were similar in logistic regression, random forest, XGBoost and deep learning models, developed with data from a single session. When combining data from the previous three sessions, the prediction performance of the deep learning model improved and became superior to that of other models. The common top-ranked features for IDH prediction were mean systolic BP (SBP) during the previous session, UF target rate, pre-dialysis SBP, and IDH experience during the previous session. CONCLUSIONS: Our AI model predicts IDH accurately, suggesting it as a reliable tool for HD treatment.

Natural behaviours after guided growth for idiopathic genu valgum correction: comparison between percutaneous transphyseal screw and tension-band plate.

BACKGROUND: Percutaneous epiphysiodesis using a transphyseal screw (PETS) or tension-band plating (TBP) has shown favourable correction results; however, the physeal behaviours in terms of rebound, stable correction, or overcorrection after guided growth have not been completely understood. In patients with idiopathic genu valgum, we therefore asked: (1) How is the correction maintained after implant removal of guided growth? (2) Is there any difference in the natural behaviours after PETS or TBP removal at the femur and tibia? METHODS: We retrospectively reviewed 73 skeletally immature limbs with idiopathic genu valgum treated with PETS or TBP. PETS was performed in 23 distal femurs and 13 proximal tibias, and TBP was performed in 27 distal femurs and ten proximal tibias. Mechanical axis deviation (MAD), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle were measured at pre-correction, implant removal, and final follow-up. Changes of ≤ 3° in mechanical angles after implant removal were considered stable. Comparisons between the implant, anatomical site, and existence of rebound were performed. RESULTS: The mean MAD improved from - 18.8 mm to 11.3 mm at implant removal and decreased to -0.2 mm at the final follow-up. At the final follow-up, 39 limbs (53.4%) remained stable and only 12 (16.4%) were overcorrected. However, 22 limbs (30.1%) showed rebound. TBP was more common, and the correction period was longer in the rebound group (p < 0.001 and 0.013, respectively). In femurs treated with PETS, the mean mLDFA increased from 86.9° at implant removal to 88.4° at the final follow-up (p = 0.031), demonstrating overcorrection. However, a significant rebound from 89.7° to 87.1° was noted at the femur in the TBP group (p < 0.001). The correction of the proximal tibia did not change after implant removal. CONCLUSION: The rebound was more common than overcorrection after guided growth; however, approximately half the cases demonstrated stable correction. The overcorrection occurred after PETS in the distal femur, while cases with TBP had a higher probability of rebound. The proximal tibia was stable after implant removal. The subsequent physeal behaviours after each implant removal should be considered in the guided growth.

Healing Predictors of Conservative Treatment for Juvenile Osteochondritis Dissecans of the Talus.

OBJECTIVE: To investigate the healing response of juvenile osteochondritis dissecans (JOCD) of the talus after conservative treatment, identify healing predictors, and develop a predictive model for healing. DESIGN: Retrospective study. SETTING: Clinics at a tertiary-level pediatric medical center. PATIENTS: Fifty-five patients (55 ankles) who presented with JOCD. INTERVENTIONS: Patients were managed with cast immobilization followed by activity restriction. MAIN OUTCOME MEASURES: The primary outcome measure of progressive lesion reossification was determined from the latest radiograph, after at least 6 months of nonoperative treatment. Final clinical evaluation was performed by a questionnaire and complementary telephone interview. Multivariate logistic regression was used to determine the influence of age, sex, lesion size, classification, location, duration of symptoms, containment lesion, and the occurrence of cyst-like lesions on healing potential. RESULTS: After nonoperative treatment, 18 (33%) of 55 lesions had failed to progress toward healing. An older age (P = 0.034) and a completely detached but undisplaced (grade III) lesion (P < 0.001) at the time of diagnosis were predictive for the failure of conservative treatment. A multivariate logistic regression best predictor model that included age and grade resulted in the best predicted healing and yielded an area under the curve of 0.920 (P < 0.001). CONCLUSION: In two-thirds of skeletally immature patients, conservative treatment resulted in the progressive healing of JOCD of the talus. For older patients with grade III lesions showing a lower healing probability, surgical treatment should be considered.

Validity and reliability of a Korean version of the Consultation and Relational Empathy (CARE) measure.

BACKGROUND: No validated tool is available to assess patients' perception of physician empathy in Korea. The objective of this study was to establish a Korean version of the Consultation and Relational Empathy (CARE) measure-originally developed in English and widely used internationally-and to examine its reliability and validity. METHODS: The CARE measure was translated into Korean and tested on 240 patients from one secondary care hospital and one tertiary care hospital in Korea. Internal consistency by Cronbach's alpha, exploratory analysis, and confirmatory factor analysis were conducted to verify the 10 items of the Korean CARE measure. RESULTS: The Korean CARE measure demonstrated high acceptability and face validity, excellent internal reliability (Cronbach's alpha = 0.97) and moderate test-retest reliability (Pearson correlation coefficient = 0.53; Spearman correlation coefficient = 0.51). Distribution of scores showed negative skewedness. Corrected item-total correlations ranged from 0.77-0.92, indicating homogeneity. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.949, and Bartlett's test of sphericity was good (χ2 = 3157.11, P < 0.001). Factor analysis yielded a single dimensional structure of physician empathy with all factor loadings exceeding 0.80 and showing excellent goodness of fit. CONCLUSION: This study supports the reliability and validity of the Korean CARE measure in a university hospital setting in Korea.

Effects of Prolonged Dual Antiplatelet Therapy in ST-Segment Elevation vs. Non-ST-Segment Elevation Myocardial Infarction.

BACKGROUND: The benefits and risks of prolonged dual antiplatelet therapy (DAPT) have not been studied extensively across a broad spectrum of acute coronary syndromes. In this study we investigated whether treatment effects of prolonged DAPT were consistent in patients presenting with ST-segment elevation myocardial infarction (STEMI) vs. non-STEMI (NSTEMI).Methods and Results:As a post hoc analysis of the SMART-DATE trial, effects of ≥12 vs. 6 months DAPT were compared among 1,023 patients presenting with STEMI and 853 NSTEMI patients. The primary outcome was a composite of recurrent myocardial infarction (MI) or stent thrombosis at 18 months after the index procedure. Compared with the 6-month DAPT group, the rate of the composite endpoint was significantly lower in the ≥12-month DAPT group (1.2% vs. 3.8%; hazard ratio [HR] 0.31, 95% confidence interval [CI] 0.12-0.77; P=0.012). The treatment effect of ≥12- vs. 6-month DAPT on the composite endpoint was consistent among NSTEMI patients (0.2% vs. 1.2%, respectively; HR 0.20, 95% CI 0.02-1.70; P=0.140; Pinteraction=0.718). In addition, ≥12-month DAPT increased Bleeding Academic Research Consortium (BARC) Type 2-5 bleeding among both STEMI (4.4% vs. 2.0%; HR 2.18, 95% CI 1.03-4.60; P=0.041) and NSTEMI (5.1% vs. 2.2%; HR 2.37, 95% CI 1.08-5.17; P=0.031; Pinteraction=0.885) patients. CONCLUSIONS: Compared with 6-month DAPT, ≥12-month DAPT reduced recurrent MI or stent thrombosis regardless of the type of MI at presentation.

Hypertension-Mediated Organ Damage and Long-term Cardiovascular Outcomes in Asian Hypertensive Patients without Prior Cardiovascular Disease.

BACKGROUND: Hypertension-mediated organ damage (HMOD), comprising structural and functional changes in arteries or end organs, is a marker of cardiovascular (CV) disease. However, there are limited data on evaluation of risk of CV disease regarding HMOD, especially in Asians. We sought to investigate the association between CV events and HMOD, and we tried to determine the most important diagnostic marker among the component of HMOD for prevention of mortality and CV events in treated Korean hypertensive patients. METHODS: From January 2008 to December 2010, a total of 35,000 hypertensive Vietnamese War veterans who consecutively visited our hospital for medical check-up were reviewed, and 6,158 patients without established CV disease were enrolled. The patients were divided into two groups as follows: HMOD group (n = 766) and non-HMOD group (n = 5,392). The primary outcome was all-cause death. RESULTS: Median age was 63.3 years (interquartile range [IQR], 61.4-65.4), and median follow-up was 6.6 years (IQR, 5.9-7.2). Patients with old age, diabetes, and chronic kidney disease were more prevalent in the HMOD group than in the non-HMOD group (all P < 0.05). The lipid profiles were not significantly different between the two groups. Nephropathy was the most prevalent (54.7%) organ damage in the HMOD group. The 6-year incidence of all-cause death was higher in the HMOD group than in the non-HMOD group (22.5% vs. 9.0%; adjusted hazard ratio [HR], 1.42; 95% confidence interval [CI], 1.01-2.00; P = 0.04). The incidence of cardiac death, ischemic heart disease, and ischemic and hemorrhagic stroke were also significantly higher in the HMOD group than in the non-HMOD group (P < 0.05, respectively). In multivariate analysis, proteinuria (adjusted HR, 2.21; 95% CI, 1.52-3.20; P < 0.001) was the most powerful independent risk factor to predict all-cause death among components of HMOD. As the degree of proteinuria increased, the rate of all-cause death also increased (long-rank P < 0.001). CONCLUSION: HMOD was associated with increased risk of mortality and CV events. Proteinuria was the most powerful independent risk factor for all-cause death, and the degree of proteinuria and mortality rate were proportional. Our data suggest that monitoring of the proteinuria is important to predict long-term CV events in hypertensive patients.

Motion Artifact Reduction in Wearable Photoplethysmography Based on Multi-Channel Sensors with Multiple Wavelengths.

Photoplethysmography (PPG) is an easy and convenient method by which to measure heart rate (HR). However, PPG signals that optically measure volumetric changes in blood are not robust to motion artifacts. In this paper, we develop a PPG measuring system based on multi-channel sensors with multiple wavelengths and propose a motion artifact reduction algorithm using independent component analysis (ICA). We also propose a truncated singular value decomposition for 12-channel PPG signals, which contain direction and depth information measured using the developed multi-channel PPG measurement system. The performance of the proposed method is evaluated against the R-peaks of an electrocardiogram in terms of sensitivity (Se), positive predictive value (PPV), and failed detection rate (FDR). The experimental results show that Se, PPV, and FDR were 99%, 99.55%, and 0.45% for walking, 96.28%, 99.24%, and 0.77% for fast walking, and 82.49%, 99.83%, and 0.17% for running, respectively. The evaluation shows that the proposed method is effective in reducing errors in HR estimation from PPG signals with motion artifacts in intensive motion situations such as fast walking and running.

6-month versus 12-month or longer dual antiplatelet therapy after percutaneous coronary intervention in patients with acute coronary syndrome (SMART-DATE): a randomised, open-label, non-inferiority trial.

BACKGROUND: Current guidelines recommend dual antiplatelet therapy (DAPT) of aspirin plus a P2Y12 inhibitor for at least 12 months after implantation of drug-eluting stents (DES) in patients with acute coronary syndrome. However, available data about the optimal duration of DAPT in patients with acute coronary syndrome undergoing percutaneous coronary intervention are scant. We aimed to investigate whether a 6-month duration of DAPT would be non-inferior to the conventional 12-month or longer duration of DAPT in this population. METHODS: We did a randomised, open-label, non-inferiority trial at 31 centres in South Korea. Patients were eligible if they had unstable angina, non-ST-segment elevation myocardial infarction, or ST-segment elevation myocardial infarction, and underwent percutaneous coronary intervention. Enrolled patients were randomly assigned, via a web-based system by computer-generated block randomisation, to either the 6-month DAPT group or to the 12-month or longer DAPT group, with stratification by site, clinical presentation, and diabetes. Assessors were masked to treatment allocation. The primary endpoint was a composite of all-cause death, myocardial infarction, or stroke at 18 months after the index procedure in the intention-to-treat population. Secondary endpoints were the individual components of the primary endpoint; definite or probable stent thrombosis as defined by the Academic Research Consortium; and Bleeding Academic Research Consortium (BARC) type 2-5 bleeding at 18 months after the index procedure. The primary endpoint was also analysed per protocol. This trial is registered with ClinicalTrials.gov, number NCT01701453. FINDINGS: Between Sept 5, 2012, and Dec 31, 2015, we randomly assigned 2712 patients; 1357 to the 6-month DAPT group and 1355 to the 12-month or longer DAPT group. Clopidogrel was used as a P2Y12 inhibitor for DAPT in 1082 (79·7%) patients in the 6-month DAPT group and in 1109 (81·8%) patients in the 12-month or longer DAPT group. The primary endpoint occurred in 63 patients in the 6-month DAPT group and in 56 patients in the 12-month or longer DAPT group (cumulative event rate 4·7% vs 4·2%; absolute risk difference 0·5%; upper limit of one-sided 95% CI 1·8%; pnon-inferiority=0·03 with a predefined non-inferiority margin of 2·0%). Although all-cause mortality did not differ significantly between the 6-month DAPT group and the 12-month or longer DAPT group (35 [2·6%] patients vs 39 [2·9%]; hazard ratio [HR] 0·90 [95% CI 0·57-1·42]; p=0·90) and neither did stroke (11 [0·8%] patients vs 12 [0·9%]; 0·92 [0·41-2·08]; p=0·84), myocardial infarction occurred more frequently in the 6-month DAPT group than in the 12-month or longer DAPT group (24 [1·8%] patients vs ten [0·8%]; 2·41 [1·15-5·05]; p=0·02). 15 (1·1%) patients had stent thrombosis in the 6-month DAPT group compared with ten (0·7%) in the 12-month or longer DAPT group (HR 1·50 [95% CI 0·68-3·35]; p=0·32). The rate of BARC type 2-5 bleeding was 2·7% (35 patients) in the 6-month DAPT group and 3·9% (51 patients) in the 12-month or longer DAPT group (HR 0·69 [95% CI 0·45-1·05]; p=0·09). Results from the per-protocol analysis were similar to those from the intention-to-treat analysis. INTERPRETATION: The increased risk of myocardial infarction with 6-month DAPT and the wide non-inferiority margin prevent us from concluding that short-term DAPT is safe in patients with acute coronary syndrome undergoing percutaneous coronary intervention with current-generation DES. Prolonged DAPT in patients with acute coronary syndrome without excessive risk of bleeding should remain the standard of care. FUNDING: Abbott Vascular Korea, Medtronic Vascular Korea, Biosensors Inc, and Dong-A ST.

Group randomized trial of teaching tobacco-cessation counseling to senior medical students: a peer role-play module versus a standardized patient module.

BACKGROUND: An important barrier to smoking-cessation counseling for physicians is a lack of education at the undergraduate level. Interactive methods such as peer role-play (RP) or modules utilizing standardized patients (SPs) may be effective for medical students to enhance their performance on tobacco cessation counseling. This study compared the effectiveness of a module using SPs to that of a RP module for undergraduate medical students on tobacco cessation counseling. METHODS: This study was conducted over a single week of the family medicine clerkship. One hundred and thirteen fourth-year medical students were randomized into either the SP group or the RP group. A RP module involved a ten-minute encounter between the student doctor and the student patient followed by five minutes of feedback from the observer student using a group developed checklist. In a SP module, each student was asked to interview a SP portraying a smoker with willingness to quit. After the encounter, the SP provided five minutes of direct oral feedback to the student. In both modules, the total intervention lasted three-and-half hours and was supervised by faculty staff. Students' objective structured clinical examination (OSCE) scores were evaluated to determine their tobacco cessation counseling skills. Four evaluation periods were conducted at baseline, postintervention, post-clerkship, and before receiving the Korean medical licensing examination (KMLE). Students' smoking knowledge test scores and counseling self-confidence levels at pre- and post-intervention were also compared. RESULTS: In both groups, post-intervention OSCE scores increased significantly compared to baseline (Cohen's d 0.87, p < 0.001 in SP group; d 0.77, p < 0.001 in RP group). However, there were no differences between the two groups. Students achieved the highest OSCE score for smoking-cessation counseling before the KMLE. After training, student self-confidence and smoking-knowledge test scores increased significantly, regardless of the type of module. Self-confidence was higher in the SP group compared with the RP group (d 0.37, p = 0.01). CONCLUSIONS: Peer role-play may be equivalent to the SP method with regard to knowledge and skills reported during smoking-cessation counseling and SP method may be better in self-confidence. Cost and student self-confidence may be important factors when choosing among the teaching methods for smoking-cessation counseling.

Functional recovery of daily living and sports activities after cosmetic bilateral tibia lengthening.

PURPOSE: The aims of this study were to evaluate the recovery of physical function and to investigate whether there are factors that adversely affect functional recovery after cosmetic bilateral lengthening of the tibia. METHODS: One hundred twenty-five healthy individuals who had undergone bilateral cosmetic tibia lengthening by the lengthening and then nail (LATN) method, lengthening over intramedullary nail (LON) method or intramedullary skeletal kinetic distractor (ISKD) were included in the study. Functional outcomes were evaluated using the Sports Activity Rating Scale (SARS), International Knee Documentation Committee (IKDC) Subjective Knee Form and patient self-reported ability scores. RESULTS: SARS and IKDC scores decreased at post-operative one year and improved significantly at post-operative two years. SARS and IKDC scores recovered similarly to pre-operative levels. Average patient self-reported ability scores at post-operative two years were 94.6 and 89.9 for daily living and light sports, respectively. However, the average score for moderate-to-strenuous sports was 68.1 and 39 patients (31.2%) recorded below average score for the moderate-to-strenuous sports. CONCLUSIONS: Patients who had undergone bilateral cosmetic tibial lengthening may expect almost full recovery of daily and light sports activities at post-operativetwo years. However, several patients may feel some limitation in moderate-to-strenuous sports activities.

Wing inertia as a cause of aerodynamically uneconomical flight with high angles of attack in hovering insects.

Flying insects can maintain maneuverability in the air by flapping their wings, and, to save energy, the wings should operate following optimal kinematics. However, unlike conventional rotary wings, insects operate their wings at aerodynamically uneconomical and high angles of attack (AoA). Although insects have continuously received attention from biologists and aerodynamicists, the high AoA operation in insect flight has not been clearly explained. Here, we used a theoretical blade-element model to examine the impact of wing inertia on the power requirement and flapping AoA, based on 3D free-hovering flight wing kinematics of a horned beetle, Allomyrinadichotoma The relative simplicity of the model allowed us to search for the best AoA distributed along the wingspan, which generate the highest vertical force per unit power. We show that, although elastic elements may be involved in flight muscles to store and save energy, the insect still has to use substantial power to accelerate its wings, because inertial energy stores should be used to overcome aerodynamic drag before being stored elastically. At the same flapping speed, a wing operating at a higher AoA requires lower inertial torque, and therefore lower inertial power output, at stroke reversals than a wing operating at an aerodynamically optimal low AoA. An interactive aerodynamic-inertial effect thereby enables the wing to flap at sufficiently high AoA, which causes an aerodynamically uneconomical flight in an effort to minimize the net flight energy.

Hemiepiphysiodesis for Idiopathic Genu Valgum: Percutaneous Transphyseal Screw Versus Tension-band Plate.

BACKGROUND: The aim of this study was to compare the outcomes of angular deformity correction by percutaneous hemiepiphysiodesis using transphyseal screw (PETS) or tension-band plating (TBP) in growing children with idiopathic genu valgum with emphasis on the rate of deformity correction. METHODS: We retrospectively reviewed cases of hemiepiphysiodesis for angular deformity in lower extremities between 2009 and 2014. A total of 90 limbs in 33 patients received PETS and 60 limbs in 24 patients received TBP. Angular measurements were compared preoperatively and at the time of hardware removal. The amount and rate of angular deformity correction were compared between the 2 groups. Potential factors affecting correction velocity were investigated using multivariate analysis. RESULTS: Angular correction was achieved in all patients. The mean rate of correction was more rapid with PETS than with TBP at both the distal femur (0.92 vs. 0.64 deg./mo, respectively; P<0.001) and proximal tibia (0.72 vs. 0.55 deg./mo, respectively; P=0.019). Multivariate analysis showed that the used implant significantly affected the rate of correction: PETS demonstrated faster correction velocity than TBP (-0.26, 95% confidence interval, -0.35 to -0.17, P<0.001). CONCLUSIONS: Both PETS and TBP techniques result in satisfactory correction of coronal angular deformity in patients with idiopathic genu valgum. However, the observed rate of correction was faster with PETS than TBP. Correction with PETS, rather than TBP, may better serve patients near skeletal maturity. LEVEL OF EVIDENCE: Level III-retrospective comparative series.

What is the best treatment for displaced Salter-Harris II physeal fractures of the distal tibia?

Background and purpose - The optimal treatment of displaced Salter-Harris (SH) II fractures of the distal tibia is controversial. We compared the outcomes of operative and nonoperative treatment of SH II distal tibial fractures with residual gap of >3 mm. Factors that may be associated with the incidence of premature physeal closure (PPC) were analyzed. Patients and methods - We retrospectively reviewed 95 patients who were treated for SH II distal tibial fractures with residual gap of >3 mm after closed reduction. Patients were assigned to 1 of 2 groups: Group 1 included 25 patients with nonoperative treatment, irrespective of size of residual gap (patients treated primarily at other hospitals). Group 2 included 70 patients with operative treatment. All patients were followed for ≥ 12 months after surgery, with a mean follow-up time of 21 months. Logistic regression analyses were performed to identify risk factors for the occurrence of PPC. Results - The incidence of PPC in patients who received nonoperative treatment was 13/52, whereas PPC incidence in patients who received operative treatment was 24/70 (p = 0.1). Multivariable logistic regression analysis determined that significant risk factors for the occurrence of PPC were age at injury, and injury mechanism. The method of treatment, sex, presence of fibular fracture, residual displacement after closed reduction, and implant type were not predictive factors for the occurrence of PPC. Interpretation - Operative treatment for displaced SH II distal tibial fractures did not seem to reduce the incidence of PPC compared with nonoperative treatment. We cannot exclude that surgery may be of value in younger children with pronation-abduction or pronation-external rotation injuries.