Torsional Rotation Research Articles

Association Between Tibial Malunion Deformity Parameters and Degenerative Hip and Knee Disease.

Tibia fractures are the most common long bone fracture. Criteria for closed and open reduction are based on the amount of fracture shortening, angulation, and rotation, with high success rates achieved if acceptable alignment is maintained. However, there exists limited data available regarding the long-term consequences of specific deformation patterns. The tibiae of 2898 cadaveric skeletons were manually inspected for evidence of fracture. Specimens with midshaft fractures were identified as candidates for study; intraarticular fractures were excluded. Fracture shortening, location, angulation, rotation (torsion), and translation were measured using previously described techniques. Degenerative joint disease of the knee and hip was graded from 0 to 3 in fracture specimens using a previously published system. Correlations between fracture characteristic and osteoarthritis were evaluated. Thirty-seven tibia fractures were present in 36 skeletons. In patients with tibia fractures, ipsilateral knee arthritis was greater than that of the contralateral side (P < 0.001). Knee arthritis was greater in fractures with coronal plane deformity greater than 5 degrees (P = 0.006) and with rotational deformity greater than 10 degrees (P = 0.004). There were no differences in knee arthritis based on laterality, shortening, sagittal deformity, fracture type, or translation in any plane (P > 0.05 for all). There were no differences in hip arthritis on the ipsilateral side compared with the contralateral side (P = 0.149). However, tibiae that were shortened by more than 10 mm had higher grades of ipsilateral hip arthritis (P = 0.009). The results of this study suggest that coronal and axial plane malalignment and shortening are of the greatest consequence following tibia fracture. These conclusions strengthen the recommendations of authors who have emphasized restoring tibial length following fracture, and providing anatomic restoration in the coronal and axial planes.

Comprehensive long-term outcomes 13.5 years following selective dorsal rhizotomy

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p < 0.001) and was significantly related to the FPA (p ≤ 0.01). Femoral torsion was related to hip internal rotation (p < 0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

Are the medial gastrocnemius muscles of spastic cerebral palsy children altered following repeat botulinum toxin injections when compared with an un-injected muscle?

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p < 0.001) and was significantly related to the FPA (p ≤ 0.01). Femoral torsion was related to hip internal rotation (p < 0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

Explorative analysis into the association between gait kinematics and energy cost in children with cerebral palsy

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p < 0.001) and was significantly related to the FPA (p ≤ 0.01). Femoral torsion was related to hip internal rotation (p < 0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

Myocardial torsional deformations in cats with hypertrophic cardiomyopathy using two-dimensional speckle-tracking echocardiography

ObjectivesThe objective of our study was to quantitatively measure systolic torsional deformations in cats with hypertrophic cardiomyopathy (HCM) and in controls. AnimalsTwenty-six client-owned cats with HCM and 14 healthy cats. HCM cats were categorized based on their symptoms (asymptomatic and symptomatic) and with or without left ventricular outflow tract obstruction (obstructive and non-obstructive). MethodsThe cats were examined for myocardial deformations using two-dimensional speckle-tracking echocardiography and were evaluated for peak systolic rotation and the rotation rate at each basal and apical view. Cats were also evaluated for the peak systolic torsion and torsion rate. ResultsThe peak systolic apical rotation and torsion were higher in asymptomatic and symptomatic cats with HCM than in control cats. Also, the peak systolic apical rotation, apical rotation rate, torsion, and torsion rate were higher in cats with obstructive HCM than in control cats. ConclusionsMyocardial torsional deformations assessed by two-dimensional speckle-tracking echocardiography may be useful for evaluating compensatory myocardial function of HCM.

Learning to walk: Identifying independent components and gait domains in newly walking infants

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p < 0.001) and was significantly related to the FPA (p ≤ 0.01). Femoral torsion was related to hip internal rotation (p < 0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

Long-term follow-up after Tibialis Anterior Tendon Shortening in combination with Achilles Tendon Lengthening in spastic equinus in cerebral palsy

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p < 0.001) and was significantly related to the FPA (p ≤ 0.01). Femoral torsion was related to hip internal rotation (p < 0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

The rotational profile: A study of lower limb axial torsion, hip rotation, and the foot progression angle in healthy adults

The purpose of this study was to compare the rotational profile of adults with higher versus lower foot progression angles (FPA). Tibial torsion, femoral torsion, hip internal and external rotation and FPA data were collected on one hundred two healthy volunteers. Data were stratified into Low, Mid, and High FPA groups to study relationships among the components of the rotational profile and if there were group differences in the magnitude of torsion angles. Direction of torsion was also studied as an attempt to look at the incidence of offsetting between the tibia and femur. Tibial torsion was significantly higher in the High FPA group (p<0.001) and was significantly related to the FPA (p≤0.01). Femoral torsion was related to hip internal rotation (p<0.05). Offsetting tibial and femoral torsions occurred in 59% of subjects with low FPA and 56% of subjects with high FPA. All subjects in the low FPA group with offsetting had tibial torsion that followed the FPA and the femurs that were directed opposite. In the High FPA group, 68% of subjects with offsetting had tibias that followed the FPA. Stratifying the data by FPA revealed there were significant differences in tibial torsion among the groups and provided evidence that tibial torsion influences the direction and magnitude of the FPA. Offsetting torsions between the tibia and femur were more common in people with higher and lower FPA and had clearer patterns where the tibia tended to follow the direction of the FPA.

Finite element modeling of cable galloping vibrations. Part II: Application to an iced cable in 1:2 multiple internal resonance

The aim of this paper is to validate the finite element formulations proposed in a companion paper for the study of the nonlinear dynamic behavior of cable structures. A well-known suspended cable in multiple 1:2 “internal resonance” conditions is herein considered. A uniform ice deposit, along the length of the cable, makes it prone to galloping vibrations under a steady wind flow. Different modeling strategies, relying on different assumptions regarding both the mechanical model as well as the aerodynamic response, are investigated and compared with results coming from analytical, semi-analytical and numerical models from the literature. The role of torsional and flexural stiffness terms, and of the initial undeformed configuration, is critically assessed. The results obtained show the significant effect coming from the adoption of a beam finite element formulation that includes the effect of torsional rotation in the evaluation of the aerodynamic loads.

Self-Restricted Green Fluorescent Protein Chromophore Analogues: Dramatic Emission Enhancement and Remarkable Solvatofluorochromism.

The confinement effect of the β-barrel defines the emission profiles of the chromophores of the green fluorescent protein (GFP) family. Here, we describe the design strategy and mimicking of confinement effects via the chromophore itself, termed the self-restricted effect. By systematically tailoring the GFP core, a family of 2,5-dialkoxy-substituted GFP chromophore analogues is found to be highly emissive and show remarkable solvatofluorochromism in fluid solvents. Fluorescence quantum yield (QY) and lifetime measurements, in combination with theoretical calculations, illustrate the mechanism relying on inhibition of torsional rotation around the exocyclic CC bond. Meanwhile, theoretical calculations further reveal that the electrostatic interaction between the solvent and the imidazolinone oxygen can contribute to suppress the radiationless decay channel around the exocyclic C═C double bond. Our findings put forward a universal approach toward unlocked highly emissive GFPc analogues, potentially promoting the understanding of the photophysics and biochemical application of GFP chromophore analogues.

Dynamic polarization vision in mantis shrimps.

Gaze stabilization is an almost ubiquitous animal behaviour, one that is required to see the world clearly and without blur. Stomatopods, however, only fix their eyes on scenes or objects of interest occasionally. Almost uniquely among animals they explore their visual environment with a series pitch, yaw and torsional (roll) rotations of their eyes, where each eye may also move largely independently of the other. In this work, we demonstrate that the torsional rotations are used to actively enhance their ability to see the polarization of light. Both Gonodactylus smithii and Odontodactylus scyllarus rotate their eyes to align particular photoreceptors relative to the angle of polarization of a linearly polarized visual stimulus, thereby maximizing the polarization contrast between an object of interest and its background. This is the first documented example of any animal displaying dynamic polarization vision, in which the polarization information is actively maximized through rotational eye movements.

GBT-based finite element to assess the buckling behaviour of steel–concrete composite beams

In this paper, an accurate and computationally efficient Generalised Beam Theory (GBT) finite element is proposed, which makes it possible to calculate buckling (bifurcation) loads of steel–concrete composite beams subjected to negative (hogging) bending. Two types of buckling modes are considered, namely (i) local (plate-like) buckling of the web, possibly involving a torsional rotation of the lower flange, and (ii) distortional buckling, combining a lateral displacement/rotation of the lower flange with cross-section transverse bending. The determination of the buckling loads is performed in two stages: (i) a geometrically linear pre-buckling analysis is first carried out, accounting for shear lag and concrete cracking effects, and (ii) an eigenvalue buckling analysis is subsequently performed, using the calculated pre-buckling stresses and allowing for cross-section in-plane and out-of-plane (warping) deformation. The intrinsic versatility of the GBT approach, allowing the incorporation of a relatively wide range of assumptions, is used to obtain a finite element with a reasonably small number of DOFs and, in particular, able to comply with the principles of the “inverted U-frame” model prescribed in Eurocode 4 [1]. Several numerical examples are presented, to illustrate the application of the proposed GBT-based finite element and provide clear evidence of its capabilities and potential.

Molecular dynamics simulation of a DNA duplex labeled with triarylmethyl spin radicals

All-atom molecular dynamics simulation of aqueous solution of DNA duplex with triarylmethyl (TAM) spin labels attached to its ends through piperazine linkers has been carried out. The dynamics and structure of the resulting molecule on time scales up to 2μs has been studied. Two classes of specific conformations have been observed. In the first one, a duplex retains its structure, and the labels on the average are arranged above the end bases of the duplex. Another class is related to the appearance of fraying at the duplex ends, i.e. involves situations where bonds between the end bases are broken, and the end pair is open. In this case, the labels get additional opportunities for the movement. Furthermore, due to torsional rotations in the linker, large deviations from the equilibrium states are possible. It is discussed the detected fraying of duplex labeled with TAM is not the inevitable result of the impact of labels. Our additional simulation has shown that fraying also occurs in the duplex without labels. Thus, despite its size, the TAM spin label does not critically influence the structure of the duplex. The distribution of distance between the labels for conformations of duplex without fraying has been shown to be in good agreement with the experimental distribution measured by pulsed EPR for the same molecule immobilized on a substrate in an aqueous solution.

Sex Differences in Static Lower Extremity Alignment in Korean Collegiate Student

Lower extremity alignment (LEA) characteristics have been reported as potential risk factor that can cause ACL injuries during a variety of sports events. Even though there seems to be different relationship among LEA between male and female, gender difference in alignment however, has not been widely investigated in Korea. PURPOSE: To compare gender differences of static LEA in the Korean collegiate student. METHODS: A total of 66 subjects (34M: age = 21.1 ± 3.1 years, height = 176.0 ± 6.7 cm, mass = 71.5 ± 8.4 kg; 32F: age= 21.0 ± 1.7 years, height = 163.6 ± 5.0 cm, mass = 56.8 ± 5.4 kg) participated in this study. Seven static LEA [hip anteversion, quadriceps angle (Q-angle), rearfoot angle, tibial varum, tibial torsion, pelvic angle, navicular drop] were measured by a single investigator. All alignments were measured only on the dominant. Cohen’s effect size was calculated in order to identify the magnitude of differences. A confidence interval of 95% was calculated to find any significant differences. RESULTS: Females have a significantly greater Q-angle [M= 13.21° ± 3.76°, F=18.95° ± 4.14°, ES = -1.46 (CI: -2.41 to -0.5)]. Even though the results were not significantly different (moderate high effect size), females have greater hip anteversion [M=6.35° ± 6.88°, F=10.38° ± 6.06°, ES = -0.62 (-2.19 to 0.95)] than males, while males have a greater external rotational tibial torsion [M=21.03° ± 7.09°, F=16.59° ± 6.76°, ES = 0.64 (-1.03 to 2.31)]. CONCLUSIONS: In the case of Koreans, there was no anecdotal difference of ACL injury between the sexes. Based upon this study, the sex differences of static LEAs were only indicated in the Q-angles of the two sexes. In previous studies not only Q-angle but multiple LEA such as Tibiofemoral angle, WB Q-angle, anterior pelvic tilt, femoral anteversion, genu recurvatum were significantly different between male and female. Thus, further study is necessary to identify ethnic difference in LEA as well as any differences in dynamic alignment among different sexes. Sponsored by IOC Medical and Scientific Commission Research Center for Prevention of Injury and Promotion of Athletic Health Grant

The torsional and rotation–torsion spectra of CD2HOH

The torsional and rotation–torsion spectra of the doubly deuterated species of methanol CD2HOH have been analyzed using submillimeter wave, terahertz, and far infrared spectra. 101 torsional subbands, with subband centers ranging from 2.3 to 626cm−1, were assigned. Analysis of these yielded kinetic energy and hindering potential parameters of the torsional Hamiltonian describing the large amplitude internal rotation of the CD2H methyl group with respect to the hydroxyl group. 3271 rotation and rotation–torsion transitions, involving the 24 torsional levels up to e1 with 3⩽K⩽10, were assigned and fitted approximating the rotational energy of each torsional level with a Taylor-type expansion in J(J+1). The rotational structure of 48 torsional subbands involving torsional levels higher than e1 has also been analyzed. In most cases, only the Q branch could be observed and assigned.

The high-resolution FTR spectrum of ethane between 3170 and 3430 cm−1

The high resolution FTIR spectrum of ethane has been reinvestigated in the region near 3μm, where three perpendicular and one parallel infrared active bands are found.The main perpendicular band is ν4+ν10. It is shown that the perpendicular partners of the combinations ν4+2ν8 and ν4+2ν11 are coupled with each other in such a way that only one resultant mode can interact effectively with ν4+ν10, becoming detectable by intensity stealing. The third perpendicular band is found to be the hot (2ν4+ν10)−ν4, lying at about 33cm−1 below the cold ν4+ν10, because of the strong anharmonicity of the torsional mode ν4, and then well separated cold and hot transitions occur in this region. It is suggested that they could be exploited in the temperature monitoring in atmospheric and planetary spectra.The complexity and the irregular rotation–torsion structure makes an analysis of this perpendicular system not practicable, but a considerable body of new line assignments, especially for the hot transitions, have been found.We have been able to analyze the parallel band, in spite of the anomalous torsional structure, and some peculiar torsional effects show that the vibrational upper state must be the infrared active ν2+ν9+ν12(A2u).A total of 304 transitions of this active parallel band were fitted with a rms deviation of 0.0097cm−1 to derive band parameters, and interacting parameters from the perturbers 3ν4+ν11∓1+ν12∓1 and ν11±1+ν9∓1+ν12±1/ν11±1+ν9±1+ν12∓1.

Subgroup of interval exchanges generated by torsion elements and rotations

Denote by G the group of interval exchange transformations (IETs) on the unit interval. Let Gper ⊂ G be the subgroup generated by torsion elements in G (periodic IETs), and let Grot ⊂ G be the subset of 2-IETs (rotations). The elements of the subgroup G1 = hGper,Groti ⊂ G (generated by the sets Gper and Grot) are characterized constructively in terms of their Sah-Arnoux-Fathi (SAF) invariant. The characterization implies that a non-rotation type 3-IET lies in G1 if and only if the lengths of its exchanged intervals are linearly dependent over Q. In particular, G1 ( G. The main tools used in the paper are the SAF invariant and a recent result by Y. Vorobets that Gper coincides with the commutator subgroup of G. 1. A group of IETs Denote by R, Q, N the sets of real, rational and natural numbers. By a standard interval we mean a finite interval of the form X = (a,b) ⊂ R (left closed - right open). We write |X| = b − a for its length. By an IET (interval exchange transformation) we mean a pair (X,f) where X = (a,b) is a standard interval and f is a right continuous bijection f : X → X with a finite set D of discontinuities and such that the translation function γ(x) = f(x)−x is piecewise constant. The map f itself is often referred to as IET, and then X = domain(f) and D = disc(f) denote the domain (also the range) of f and the discontinuity set of f, respectively. Given an IET f : X → X, the set disc(f) partitions X into a finite number of subintervals Xk in such a way that f restricted to each Xk is a translation

Torsional Deformations in Subnanometer MoS Interconnecting Wires

We use aberration-corrected transmission electron microscopy to track the real time atomic level torsional dynamics of subnanometer wires of MoS interconnecting monolayer regions of MoS2. An in situ heating holder is used inside the transmission electron microscope to raise the temperature of the sample to 400 °C to increase crystallization rates of the wires and reduce contamination effects. Frequent rotational twisting of the MoS wire is captured, demonstrating elastic torsional deformation of the MoS wires. We show that torsional rotations of the crystal structure of the MoS wires depend upon the specific atomic structure of the anchored sections of the suspended wire and the number of unit cells that make up the wire length. Elastic torsional flexibility of the MoS wires is revealed to help their self-adapting connectivity during the structural changes. Plastic torsional deformation is also seen for MoS wires that contain defects in their crystal structure, which produce small scale rotational disorder within the wires. Upon removal of the defects, the wire returns back to pristine form. These results provide detailed insights into how the atomic structure of the anchoring site significantly influences the nanowire configurations relative to the monolayered MoS2.

A Note on Torsion of Nonlocal Composite Nanobeams

The ERINGENelastic constitutive relation is used in this paper in order to assess small-scale effects in nanobeams. Structural behavior is studied for functionally graded materials in the cross-sectional plane and torsional loading conditions. The governing boundary value problem has been formulated in a mixed framework. Torsional rotations and equilibrated moments are evaluated by solving a first-order differential equation of elastic equilibrium with boundary conditions of kinematic-type. Benchmarks examples are briefly discussed, enlightening thus effectiveness of the proposed methodology.

Apical rotation in patients with ST-elevation myocardial infarction

Objective: The aim of this study was to assess apical rotation in patients with anterior and inferior myocardial infarction (MI) by speckle-tracking echocardiography. Background: Left ventricular ejection fraction (LVEF) is the most widely used index of left ventricular (LV) systolic function. However, the development of wall-motion abnormalities after acute MI significantly decreases the accuracy of LVEF; further, calculation of LV volume by the biplane Simpson method is inaccurate, because it depends on geometric assumptions. Recently, two-dimensional speckle-tracking imaging has facilitated noninvasive measurement of LV strain and rotation. Patients and methods: The present study enrolled 54 patients with anterior or inferior MI, in addition to 20 healthy volunteers (matched for age and sex) as the control group. Basal and apical LV short-axis images were acquired for further off-line analysis. Using commercially available two-dimensional strain software, apical, basal rotation, and LV torsion were calculated. Results: Apical rotation was significantly reduced in the patient group compared with the control group (P Conclusion: There was a significant correlation between ejection fraction and apex rotation (r = 0.466, P = 0.044), torsion degree (r = 0.499, P = 0.03), and untwisting rate (r = −0.543, P Correlation with basal rotation was nonsignificant, and thus measurement of apical rotation alone (rather than calculation of LV torsion) might provide a simple and accurate alternative for assessment of LV contractility. No difference was found between anterior and inferior MI as regards torsion (P = 0.870). Apical rotation and torsion were decreased in ST-elevation MI, and this was statistically significant in patients with LV dysfunction.