Lateral Peak Research Articles

Reliability of the Single-Leg, Medial Countermovement Jump in Youth Ice Hockey Players.

Appropriate performance tests are critical for documenting training, fatigue and injury-related changes. Functional performance testing can provide quantitative information on specialized sport movements. The single-leg, medial countermovement jump is an objective measure of frontal plane force, velocity and power, and is particularly applicable for ice hockey players given that ice skating involves applying lateral forces. This study assessed the short-term reliability (10 days) of the single-leg, medial countermovement jump performed by ten competitive male youth ice hockey players. Each participant performed three right and three left maximal single-leg, medial countermovement jumps from force plates. Measured variables included lateral and vertical takeoff velocity, lateral and vertical maximal force, maximal force above bodyweight, lateral and vertical peak concentric power, average concentric power, and average concentric power during the last 100 ms of push-off. Relative reliability was quantified by intraclass correlations. Absolute reliability and the smallest real difference were also calculated. The single-leg, medial countermovement jump had moderate-to-excellent test–retest reliability (ICC: 0.50–0.98) for all twelve variables of interest. These results suggest that the single-leg, medial countermovement jump is a reliable test for assessing frontal plane force, velocity and power in ice hockey players, and is a valid functional performance test for this population given the similarity to ice skating.

The influence of kinesio taping on trunk and lower extremity motions during different landing tasks: implications for anterior cruciate ligament injury

PurposeThe purpose of the study was to investigate the influence of a 72-h KT application on trunk and lower extremity kinematics during different landing tasks.MethodsTwenty-nine competitive male athletes participated in this study. The sum of knee valgus and lateral trunk lean, symmetry index (SI), and peak angles of lateral trunk lean, hip flexion, knee abduction and flexion were assessed for all participants during single-leg drop landing (SLDL), single-leg vertical drop jump (SLVDJ), vertical drop jump (DLVDJ), and double leg forward jump (DLFJ), at baseline and seventy-two hours following KT application.ResultsThe KT application resulted in more knee flexion and abduction, sum of knee valgus and lateral trunk lean as compared with the non-KT condition during SLDL (P < 0.05). Nonetheless, there were no differences in SI, maximum angle of the lateral trunk lean during SLDL, SLVDJ, nor hip flexion, knee abduction, and flexion during DLVDJ, and DLFJ tasks (P > 0.05).ConclusionsThe research findings suggest that KT after 72-h application may improve knee abduction and sum of knee valgus and lateral trunk lean during SLDL, knee flexion during SLDL and SLVDJ in individuals displaying risky single-leg kinematics. Therefore, KT application may marginally improve high-risk landing kinematics in competitive male athletes.Level of evidenceLevel III.

Study on shear capacity of prestressed composite joints with concrete-encased CFST columns

Through assuming reasonable constitutive relation of materials, finite element analysis (FEA) models of joints consisting of prestressed concrete-encased steel beams and concrete-encased concrete filled steel tube (CFST) columns were established by soft ABAQUS, and the simulated results were compared with tested ones. On this basis, the nonlinear analysis on the total loading process was conducted, and the stress variation of concrete, profile steel skeleton, steel bar skeleton, and prestressing tendons were observed at yield, peak, and ultimate loads; the influence of axial compressive ratio, steel tube ratio, stirrup ratio, and prestressing level on lateral load-displacement curves at column top and shear force-shear angle in joint core were investigated, and the shear capacity formulae of joint core were developed. It could be concluded that, the lateral peak loads and shear capacity could be improved with the increase of axial compressive ratio, steel tube ratio, stirrup ratio, and prestressing levels in varying degrees, and the ductility of joints will reduce with the increase of axial compressive ratio. Additionally, the shear capacity calculated by proposed practical formula was a little lower than FEA results, which could keep the joints safety and could be used in engineering design.

Experimental Study on Biaxial Dynamic Compressive Properties of ECC.

An improved hydraulic servo structure testing machine has been used to conduct biaxial dynamic compression tests on eight types of engineered cementitious composites (ECC) with lateral pressure levels of 0, 0.125, 0.25, 0.5, 0.7, 0.8, 0.9, 1.0 (the ratio of the compressive strength applied laterally to the static compressive strength of the specimen), and three strain rates of 10−4, 10−3 and 10−2 s−1. The failure mode, peak stress, peak strain, deformation modulus, stress-strain curve, and compressive toughness index of ECC under biaxial dynamic compressive stress state are obtained. The test results show that the lateral pressure affects the direction of ECC cracking, while the strain rate has little effect on the failure morphology of ECC. The growth of lateral pressure level and strain rate upgrades the limit failure strength and peak strain of ECC, and the small improvement is achieved in elastic modulus. A two-stage ECC biaxial failure strength standard was established, and the influence of the lateral pressure level and peak strain was quantitatively evaluated through the fitting curve of the peak stress, peak strain, and deformation modulus of ECC under various strain rates and lateral pressure levels. ECC’s compressive stress-strain curve can be divided into four stages, and a normalized biaxial dynamic ECC constitutive relationship is established. The toughness index of ECC can be increased with the increase of lateral pressure level, while the increase of strain rate can reduce the toughness index of ECC. Under the effect of biaxial dynamic load, the ultimate strength of ECC is increased higher than that of plain concrete.

Noninvasive Assessment of Right Ventricle Function and Pulmonary Artery Pressure Using Transthoracic Echocardiography in Women With Pre-Eclampsia: An Exploratory Study.

Background and objectivePre-eclampsia (PEC) is associated with the release of anti-angiogenic factors that are incriminated in raising systemic and pulmonary vascular resistance (PVR). Compared to the left heart and systemic circulation, much less attention has been paid to the right heart and pulmonary circulation in patients with PEC. We used transthoracic echocardiography (TTE) to estimate pulmonary artery (PA) pressure and right ventricular (RV) function in women with PEC.Materials and methodsWe conducted a case-control study at a tertiary care academic center. Ten early PEC (<34-week gestation) and nine late PEC (≥34-week gestation) patients with 11 early and 10 late gestational age-matched controls were enrolled. Two-dimensional TTE was performed on all patients. The estimated mean PA pressure (eMPAP) was calculated based on PA acceleration time (PAAT). PVR was estimated from eMPAP and RV cardiac output (RV CO). RV myocardial performance index (RV MPI), tricuspid annular plane systolic excursion (TAPSE), tissue tricuspid annular displacement (TTAD), and lateral tricuspid annular tissue peak systolic velocity (S’) were measured.ResultsCompared to early controls, in early PEC, the eMPAP and estimated PVR (ePVR) were elevated, PAAT was reduced, RV MPI was increased, TTAD was reduced, and TAPSE and TV S’ were unchanged. Compared to late controls, in late PEC, the eMPAP and ePVR were elevated, PAAT was reduced, and RV MPI was increased, while TAPSE, TTAD, and TV S’ were unchanged.ConclusionsIn a sample of women with PEC, early PEC was found to be associated with increased eMPAP and ePVR and subclinical decrement of RV function as assessed by TTE. TTE may be a useful noninvasive screening tool for early detection of pulmonary hypertension and RV dysfunction in PEC. An adequately powered longitudinal study is needed to determine the implications of these findings on long-term outcomes.

A simplified iterative approach for testing the pulse derailment of light rail vehicles across a viaduct to near-fault earthquake scenarios

Near-fault (NF) earthquakes cause severe bridge damage, particularly urban bridges subjected to light rail transit (LRT), which could affect the safety of the light rail transit vehicle (“light rail vehicle” or “LRV” for short). Now when a variety of studies on the fault fracture effect on the working protection of LRVs are available for the study of cars subjected to far-reaching soil motion (FFGMs), further examination is appropriate. For the first time, this paper introduced the LRV derailment mechanism caused by pulse-type near-fault ground motions (NFGMs), suggesting the concept of pulse derailment. The effects of near-fault ground motions (NFGMs) are included in an available numerical process developed for the LRV analysis of the VBI system. A simplified iterative algorithm is proposed to assess the stability and nonlinear seismic response of an LRV-reinforced concrete (RC) viaduct (LRVBRCV) system to a long-period NFGMs using the dynamic substructure method (DSM). Furthermore, a computer simulation software was developed to compute the nonlinear seismic responses of the VBI system to pulse-type NFGMs, non-pulse-type NFGMs, and FFGMs named Dynamic Interaction Analysis for Light-Rail-Vehicle Bridge System (DIALRVBS). The nonlinear bridge seismic reaction determines the impact of pulses on lateral peak earth acceleration (Ap) and lateral peak land (Vp) ratios. The analysis results quantify the effects of pulse-type NFGMs seismic responses on the LRV operations' safety. In contrast with the pulse-type non-pulse NFGMs and FFGMs, this article's research shows that pulse-type NFGM derail trains primarily via the transverse velocity pulse effect. Hence, this study's results and the proposed method can improve the LRT bridges' seismic designs.

A Thorax Marker Set Model to Analyse the Kinematics of Walking Without the Need to Place Markers on the Back.

Previous thorax models have been proposed for gait analysis, however these require markers to be placed on the back. This presents a limitation in the kinematic analysis of the thorax under load carriage conditions. This study evaluated the validity and reliability of a thorax marker set that does not require markers to be placed on the back (HubemaLab model) when compared to 3 previously published marker set models. 17 young adults were evaluated while walking at their self-selected speed. A 12 camera motion capture system was used to acquire the marker position data which was then processed using the respective models using Visual-3D. The level of agreement for the flexion/extension peak, right/left lateral peak and right/left rotation peak of the thorax angle and angular velocity; together with the range of motion and thorax angular velocities in the three planes was found between each thorax marker set, while the reliability was measured using the intraclass correlation coefficient. The ICC results for the thorax angle ROM and the range of thorax angular velocity between the HubemaLab model and the other models showed excellent to good reliability in all three planes. While the ICCs for the peak flexion/extension, peak right/left lateral flexion and peak right/left rotation showed excellent to moderate reliability in all three planes. The new model could be potentially valuable for kinematic gait analysis under load carriage conditions which obscure markers placed on the back.

Relationships between tibial acceleration and ground reaction force measures in the medial-lateral and anterior-posterior planes

Peak vertical tibial accelerations during running have shown strong correlations with vertical ground reaction force loading rates and some associations with injury. However, little attention has been given to tibial accelerations along the medial–lateral and anterior-posterior axes. Therefore, our purpose was to examine the correlation between peak tibial accelerations and ground reaction force loading rates in the medial–lateral and posterior directions. Eighteen recreational runners were recruited who ran with a rearfoot strike pattern (10 men/ 8 women, mean age (yrs) = 33 ± 11). Tibial accelerations and ground reaction forces were collected while participants ran on an instrumented treadmill at a self-selected speed. Correlations were developed for: a) peak medial and lateral accelerations with lateral and medial loading rates, respectively, b) peak anterior tibial accelerations and posterior loading rates. Significant correlations were found between tibial accelerations and loading rates in all planes. Peak medial tibial accelerations were correlated with lateral loading rates (Rs = 0.86, p < 0.001) and peak lateral tibial accelerations were correlated with peak medial loading rates (Rs = 0.91, p < 0.001). A lower correlation was found between anterior accelerations and posterior loading rates (Rs = 0.51, p = 0.030). Tibial accelerations in the medial–lateral plane seem to be a valid surrogate for the respective ground reaction force measures during running on a treadmill, explaining 74–83% of the variance in loading rates. However, with only 26% of the variance explained, the same may not be true for anterior tibial accelerations and posterior loading rates.

P31. Lateral interface pressures during a spinal procedure: can we optimize positioning?

BACKGROUND CONTEXT Prolonged surgical procedures have an increased risk of pressure and nerve injuries. Lateral lumbar interbody fusion (LLIF) procedures require patient positioning with tape to secure and minimize movement of the patient. Decreased interface pressures have previously been attributed to increased patient comfort. We assessed the preoperative interface pressures for a LLIF procedure. PURPOSE Lateral peak interface pressures on a flat surgical table is increased with taping during patient positioning. STUDY DESIGN/SETTING Prospective. PATIENT SAMPLE Peak pressures were measured in four phases of patient positioning: lateral (n=93 frames), lateral + axilla pad (n=43 frames), lateral + axilla pad + taping (n=506 frames), and lateral + axilla pad + taping + draping (n=414 frames). Peak pressure measurements were captured over a timeframe of minimal contact to the patient. Four regions were assessed: the shoulder, right thorax, hip and leg. OUTCOME MEASURES Peak pressures (mmHg) for the shoulder, right thorax, hip, and leg regions. METHODS Pressure sensors were placed on a flat surgical table. A patient was positioned laterally according to Association of Surgical Technologists Standards of Practice for Surgical Positioning. An axilla pad was placed to support the right thorax and egg crate foam were used to support the lateral side of the right knee. Peak pressures were measured in four phases of patient positioning: lateral (n=93 frames), lateral + axilla pad (n=43 frames), lateral + axilla pad + taping (n=506 frames), and lateral + axilla pad + taping + draping (n=414 frames). Peak pressure measurements were captured over a timeframe of minimal contact to the patient. Four regions were assessed: the shoulder, right thorax, hip and leg. RESULTS Before taping to secure the patient, peak pressures for the shoulder, right thorax, hip, and leg regions were 33.4±0.5 mmHg, 59.5±0.6 mmHg, 68.4±1.0 mmHg, and 50.8±0.8 mmHg. After taping, peak pressures were significantly increased in all regions except the shoulder and legs. Peak pressures were 35.0±0.4 mmHg, 71.1±0.5 mmHg (p CONCLUSIONS Pressure sensors can provide real-time feedback during patient positioning. Securing a patient with tape increases the static pressure applied to a patient in a single position procedure. Optimal techniques to minimize excessive pressure can be identified. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Investigation of nonlinear behavior of high ductility reinforced concrete shear walls

In this study, the nonlinear behavior of ductile reinforced concrete (RC) shear walls having different parameters was analytically investigated. The purpose of this study is to determine the effect of axial load, longitudinal reinforcement ratio and transverse reinforcement ratios on the moment-curvature and lateral force-lateral peak displacement relationships of RC shear walls. RC shear walls that have various parameters were designed by taking into account the regulation of the Turkish Building Earthquake Code (TBEC, 2018). By considering the nonlinear behavior of the materials, behaviors of the RC shear walls were examined within the framework of the moment-curvature relation. The moment-curvature relations of RC shear walls with different parameters were obtained with the Mander model which takes into consideration the lateral confined concrete strength for different parameters. The effects of the analyzed parameters on the nonlinear behavior of the RC shear walls were evaluated in terms of curvature ductility, moment capacity, peak displacement, the angular displacement and displacement ductility values. It was seen that changes in the transverse reinforcement, longitudinal reinforcement, and axial load levels had important influence on the moment-curvature and lateral force-lateral peak displacement behavior of the RC shear walls.

Using a Crossline Laser to Predict Peak Plantar Pressure During Walking.

Developing low-cost assessment tools to quantify ankle biomechanics in a clinical setting may improve rehabilitation for patients with chronic ankle instability (CAI). To determine whether a crossline laser can predict peak plantar pressure during walking. Descriptive laboratory study. Laboratory. Twenty-five participants with CAI (9 men, 16 women; age = 20.8 ± 2.3 years, height = 170.4 ± 10.4 cm, mass = 78.9 ± 22.4 kg). Participants completed 30 seconds of treadmill walking with a crossline laser fixed to their shoe while, simultaneously, a video camera recorded the laser projection on the wall and an in-shoe plantar-pressure system measured plantar pressure. Peak laser rotation and peak plantar pressure of the lateral midfoot and forefoot. With respect to peak plantar pressure, peak rotation of the laser during walking explained 57% of the variance in the lateral midfoot and 64% in the lateral forefoot. The crossline laser may be a valuable clinical tool for predicting lateral peak plantar pressure in patients with CAI during walking.

EXPERIMENTAL INVESTIGATION OF SEISMIC RESPONSE PARAMETERS OF RUBBERISED AGGREGATE CONCRETE FRAME STRUCTURE

This paper presents the results of experimental investigations on a reduced-scale, reinforced, rubberised, aggregate concrete frame structure for the evaluation of seismic response parameters. The considered frame has twenty percent scrap-tyre rubber (crumb) replacing fine aggregates. A one-third reduced scale model of a two-storey single-bay frame was fabricated using the mix ratio of 1:1.68:1.72 (cement: sand: aggregate) and water/cement of 0.48, replacing twenty percent of fine aggregates via waste rubber (crumb) by volume. The model frame was subjected first to a free vibration test for evaluation of dynamic characteristics (frequency/period, elastic viscous damping). It was subjected to simulated multiple base excitations using 1994 Northridge earthquake time history for the evaluation of seismic response parameters (ductility factor, overstrength factor, and response modification factor). Seismic response curve (lateral displacement versus peak base acceleration) was developed for the model to assess the viability of crumb in concrete in areas of active seismicity. The fundamental period of vibration and damping were calculated as 0.75 sec and 10.85 percent, respectively using records of free vibration tests. The ductility, overstrength and response modification factors, and maximum acceleration resisted were computed using multiple base excitations which came out to be 3.10, 2.16, 6.70 and 0.72g, respectively.

P1261DIAGNOSTIC VALUE OF TEMPORARY OCCLUSION OF ARTERIO-VENOUS HIGH FLOW FISTULA DURING RIGHT HEART CATHETERISATION IN PATIENTS WITH PULMONARY HYPERTENSION

Abstract Background and Aims Pulmonary hypertension (PH) is prevalent in patients with functioning high-flow arterio-venous fistula (HFAVF) and associated with congestive heart failure (CHF). The real incidence and possible causes of this phenomenon is a matter of debate. Hemodynamic effects of HFAVF is considering as one of the reasons for PH formation. The subject of study was the impact of HFAVF on selected parameters of central hemodynamics. In particular, the diagnostic relevance of test of temporary HFAVF occlusion (TTO) was evaluated during right heart catheterization (RHC). Method A total of 13 patients were enrolled: 8 - after kidney transplantation (KT) with preserved allograft function and 5 - on maintenance hemodialysis (HD). All of them demonstrated clinical presentation of CHF III-IV class (NYHA). Severe PH and diastolic disfunction (DD) were observed at a baseline: echocardiographic systolic pulmonary arterial pressure sPAP (mmHg): M=59 (SD 13), ratio of mitral early diastolic inflow velocity (E) (pulsed wave Doppler) to average of septal and lateral mitral annular early-diastolic peak velocity (e′) (tissue Doppler imaging) E/e′ M=18 (SD 5). The ones who have comorbid conditions that cause PH were excluded. All patients bore an upper arm HFAVF, flow of the AVF (Qa) measured by Doppler ultrasonography was markedly high (Qa): M = 3,8 l/min (SD 1,2), the cardio-pulmonary recirculation (Qa/CO): M = 51% (SD 13). All patients underwent RHC and TTO AVF. Echocardiography (Echo) was performed initially and on the follow up (8 weeks after AVF closure/flow reduction). Statistical analysis was performed using the STATISTICA 13 software (Wilcoxon, T-test). Results The results of RHC and Echo data are presented in tables 1, 2. As can be seen from the table data, all cases demonstrated instrumental features of high output CHF (HO CHF) in accordance with patient’s clinical status. TTO of HFAVF resulted in statistically significant decrease in CO and CI values, but no changes in PAP parameters were observed. Taking into account clinical and instrumental features of advanced CHF, HF AVF was closed in 8 patients after KT and in 2 patients on HD. 3 patients on HD underwent AVF flow reduction up to Qa not exceeding 1,1 l/min. Follow-up demonstrated complete resolution of CHF and dramatic improvement of DD, reduction in CO, CI, sPAP, volume parameters. CO, cardiac output; CI, cardiac index; sPAP, systolic pulmonary arterial pressure; meanPAP, mean pulmonary arterial pressure; RAP, mean right atrial pressure; PCWP, pulmonary capillary wedge pressure; LV EDVi, left ventricular end-diastolic volume index; LAVi, left atrial volume index; RAVi, right atrial volume index; Conclusion PH is a component of AVF-induced HO CHF and could be classified as postcapillary one. TTO confirms significant HFAVF contribution to specific changes of parameters of central hemodynamics due to HO CHF. TTO does not impact on PAP values and therefore is not valid to clarify PH genesis per se.

Morphology of the mandibular gnathobases of the copepods Calanus australis and Calanoides carinatus: Evidence of omnivory

In spite of the worldwide ecological relevance of Calanus australis and Calanoides carinatus, little is known on the morphology of their mandibular gnathobase edges (MGEs). Thus, in order to further learn about the relationship between MGEs and diet, adults and copepodites of C. australis and C. carinatus collected from northern Patagonian coasts, Argentina, were morphologically analyzed using confocal laser scanning microscopy in transmission mode and scanning electron microscopy. In C. australis males as well as in C. australis and C. carinatus females, MGEs were found to end in one dorsal seta and to have one ventral tooth, four central teeth and three dorsal teeth. In contrast, in C. carinatus males, MGEs were observed to be rudimentary and with no dorsal seta, and −contrary to published data− they were found to have three cone-shaped, short and small tooth-like structures and three-four tooth-like structures that were long and pointed. The main differences between MGEs from copepodites and adults of C. australis and C. carinatus females lied in the number of cuspids observed on the different teeth and the presence of a short inner lateral peak found only in C. australis ventral tooth. Overall, the evidence gathered from our study leads us to classify C. australis and C. carinatus as omnivores.

Sprung mass positioning by semi-actively controlled damper

Recently, the intensive wear of rails, especially in curves of small radii and at switches, has been studied. The wear is caused by the high lateral force peak of the wheel against the rail when entering the curves. An effective solution for reducing undesirable lateral forces on the rail is to rotate the vehicle bogie in the direction of the rail curve, which influences the distribution of lateral force over the first and second wheelset. This reduces the force peak and thus the track wear. The bogie rotation is nowadays realized by actuators, which replace the yaw dampers. However, actuator implementation is complicated, expensive, energyintensive and demanding for the performance of a fail-safe system. From this point of view, a semi-actively controlled yaw damper appears to be a better candidate. An algorithm such as Skyhook can hold the sprung mass in the desired position. It is believed to be possible to rotate the vehicle bogie by the special S/A control strategy of a yaw damper. This paper deals with the possibilities and limits of the positioning of the sprung mass by the semi-actively controlled damper. It has been shown that the system relative attenuation and the damper response time have the greatest influence on the mass positioning efficiency.

Effects of quadriceps angle on patellofemoral contact pressure.

BackgroundAn inappropriate Q angle may affect the biomechanics of the canine patellofemoral joint.ObjectivesThe purpose of this study was to evaluate the effects of changes in quadriceps angle (Q angle) on patellofemoral joint pressure distribution in dogs.MethodsEight stifles were positioned at 45, 60, 75, 90, 105, and 120° of flexion in vitro, and 30% body weight was applied through the quadriceps. Patellofemoral contact pressure distribution was mapped and quantified using pressure-sensitive film. For the pressure area, mean pressure, peak pressure, medial peak pressure, and lateral peak pressure, differences between groups according to conditions for changing the Q angle were statistically compared.ResultsIncreases of 10° of the Q angle result in increases in the pressure area (P = 0.04), mean pressure (P = 0.003), peak pressure, and medial peak pressure (P ≤ 0.01). Increasing the Q angle by 20° increases the pressure area (P = 0.021), mean pressure (P ≤ 0.001), peak pressure (P ≤ 0.01), and medial peak pressure (P ≤ 0.01) significantly, and shows higher mean (P ≤ 0.001) and peak pressures than increasing by 10°. Decreasing the Q angle increases the mean pressure (P = 0.013), peak pressure, and lateral peak pressure (P ≤ 0.001).ConclusionsBoth increases and decreases in the Q angle were associated with increased peak patellofemoral pressure, which could contribute to the overloading of the cartilage. Therefore, the abnormal Q angle should be corrected to the physiologically normal value during patellar luxation repair and overcorrection should be avoided.

Anterior femoral cut in total knee arthroplasty: a classification proposal

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; The cut of the anterior femur (CAF) sets the rotation of the femoral component, which could affect patellar tracking, and influence the clinical results on total knee arthroplasty (TKA). The aim of this study was to suggest a classification for anterior femoral cut in TKA.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; Images of anterior femoral cuts were aggregated in different shapes and defined a classification. One-hundred femoral image’s cuts were analysed by 5 orthopaedic surgeons, which classified them twice. To analyse inter and intra-observer agreement, the Fleiss Kappa test was used.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The study proposes the following CAF classification, type 1 (one peak) and type 2 (two peaks); subtypes 1 (a) a central base peak, 1 (b) a lateral base peak, 2 (a) two peaks where the smallest is in the lower half, and 2 (b) two peaks where the smallest is in the upper half. In our study, type 2 (a) was the most common type (54.5%), followed by type 1 (b). The analysis showed good intra- and inter-observer agreements (mean K of 0.774 and 0.627, respectively). The intra and inter-observer concordance was statistically significant in all the analyses.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; The CAF classification system for TKA is considered a reproducible classification. To our knowledge, there is no study describing a shape’s classification of this cut. A slight rotation of the femoral cutting guide could change the axial rotation and positioning of the femoral component. An undesirable cut could lead to different patellofemoral offset and could consequently cause anterior pain and instability.&lt;/p&gt;

Cyclic tests on novel steel-concrete-steel sandwich shear walls with boundary CFST columns

Firstly, this paper proposed a type of steel-concrete-steel (SCS) sandwich composite shear wall with J-hook connectors (SCSSWJ) and boundary concrete-filled-steel-tube (CFST) columns. Five full-scale cyclic tests were performed to study seismic performances of SCSSWJs. The studied parameters were connectors’ spacing and axial force ratio. Test results showed that flexure failure occurred to these five SCSSWJs with boundary CFST columns, which is characterized by tensile fracture of boundary steel tube, local buckling in the edge tube and faceplates, and concrete crushing. The test results revealed that increasing the spacing of J-hook connectors from 100mm to 160mm and 200mm firstly slightly improves but then compromised the seismic behaviour of SCSSWJ due to early buckling of steel faceplate; increasing the axial force ratio significantly compromised the seismic behaviours of SCSSWJ. This paper also developed theoretical models to evaluate lateral peak shear resistance of SCSSWJ. The validations proved that the developed models predicted well lateral peak shear resistance of SCSSWJ with boundary CFST columns.

Value of dual Doppler echocardiography for prediction of atrial fibrillation recurrence after radiofrequency catheter ablation

BackgroundIncreasing evidence has been presented which suggests that left ventricular (LV) diastolic dysfunction may play an important role in the development of atrial fibrillation (AF). However, the potential for LV diastolic dysfunction to serve as a predictor of AF recurrence after radiofrequency catheter ablation remains unresolved.MethodsDual Doppler and M-PW mode echocardiography were performed in 67 patients with AF before ablation and 47 patients with sinus rhythm. The parameters measured within identical cardiac cycles included, the time interval between the onset of early transmitral flow peak velocity (E) and that of early diastolic mitral annular velocity (e’) (TE-e’), the ratio of E to color M-mode Doppler flow propagation velocity (Vp)(E/Vp), the Tei index, the ratio of E and mitral annular septal (S) peak velocity in early diastolic E/e’(S) and the ratio of E and mitral annular lateral (L) peak velocity E/e’(L). A follow-up examination was performed 1 year after ablation and patients were divided into two groups based on the presence or absence of AF recurrence. Risk estimations for AF recurrence were performed using univariate and multivariate logistic regression.ResultsTE-e’, E/Vp, the Tei index, E/e’(S) and E/e’(L) were all increased in AF patients as compared with the control group (p < 0.05). At the one-year follow-up examination, a recurrence of AF was observed in 21/67 (31.34%) patients. TE-e’ and the Tei index within the recurrence group were significantly increased as compared to the group without recurrence (p < 0.001). Results from multivariate analysis revealed that TE-e’ can provide an independent predictor for AF recurrence (p = 0.001).ConclusionsDual Doppler echocardiography can provide an effective and accurate technique for evaluating LV diastolic function within AF patients. The TE-e’ obtained within identical cardiac cycles can serve as an independent predictor for the recurrence of AF as determined at 1 year after ablation.

Increase in medial meniscal extrusion in the weight-bearing position observed on ultrasonography correlates with lateral thrust in early-stage knee osteoarthritis

BackgroundLateral thrust is known to be risk factors for knee osteoarthritis progression. Medial meniscus extrusion is also known to be risk factors for knee osteoarthritis progression; moreover, the amount of change in medial meniscus extrusion from non-weight bearing to weight bearing is an important factor for the progression of knee osteoarthritis. This study aimed to investigate the correlation between lateral thrust and the change in medial meniscus extrusion. MethodsIn total, 44 knees from 44 patients (mean age, 68.9 years) with knee osteoarthritis were divided into two groups according to the Kellgren–Lawrence grade: early-stage osteoarthritis (Kellgren–Lawrence = 2) and severe osteoarthritis (Kellgren–Lawrence = 3 or 4). The lateral thrust during gait, represented as the lateral acceleration peak immediately after heel strike, was recorded by an inertial sensor. The amount of change in medial meniscus extrusion, which was the difference between weight-bearing (unipedal standing) and non-weight-bearing (supine) conditions, was evaluated using ultrasonography. ResultsThe mean value of the lateral acceleration peak in the severe osteoarthritis group was higher than that of the early-stage osteoarthritis group (p < 0.05). The non-weight-bearing and weight-bearing medial meniscus extrusion in the severe OA group were significantly higher than those of the early-stage osteoarthritis group (p < 0.001). However, the amount of change in medial meniscus extrusion in severe osteoarthritis group was significantly lower than in the early-stage osteoarthritis group (p < 0.05). The amount of change in medial meniscus extrusion showed a significant correlation with the lateral acceleration peak in the early-stage osteoarthritis group (r = 0.56, p < 0.001). On the other hand, there was no significant correlation in the severe osteoarthritis group. ConclusionThe lateral thrust shows a positive correlation with the amount of change in medial meniscus extrusion by weight bearing in patients with early-stage knee osteoarthritis.