Sex-Specific Hip Movement Is Correlated With Pelvis and Upper Body Rotation During Running

There is a sex bias for common overuse running injuries that are associated with sex-specific hip kinematics. Gait retraining programs aimed at altering hip kinematics may be more efficient if they incorporated an understanding of how hip kinematics are correlated with the movement of the remaining body segments. We applied a principal component analysis to structure the whole-body running kinematics of 23 runners (12 ♀) into k = 12 principal movements (PMk), describing correlated patterns of upper and lower body movements. We compared the time-dependent movement amplitudes with respect to each PMk between males and females using a waveform analysis and interpreted our findings according to stick figure animations. The movement amplitudes of two PMs (PM6 and PM8) showed statistically significant effects of “sex,” which were independent of running speed. According to PM8, females showed more hip adduction, which correlated with increased transverse rotation of the pelvis and upper body compared to men. We propose that increased hip adduction and upper body rotation in female runners may be a strategy to compensate for a less efficient arm and upper body swing compared to men. Gait interventions aimed at reducing hip adduction and running-related injuries in female runners should consider instructions for both upper and lower body to maximize training efficacy.

Brane with transverse rotation and background fields: boundary state and tachyon condensation

The boundary state corresponding to the Dp-brane with a transverse rotation in the presence of the Kalb–Ramond and tachyon background fields and a U(1) internal field will be constructed. We shall investigate effects of the open string tachyon condensation on this brane via its boundary state. We demonstrate that the background fields and transverse rotation cannot protect the brane against the collapse. Our calculations are in the context of the bosonic string theory.

Analysis of the Relative Motion Between the Socket and Residual Limb in Transtibial Amputees While Wearing a Transverse Rotation Adapter

The coupling between the residual limb and the lower-limb prosthesis is not rigid. As a result, external loading produces movement between the prosthesis and residual limb that can lead to undesirable soft-tissue shear stresses. As these stresses are difficult to measure, limb loading is commonly used as a surrogate. However, the relationship between limb loading and the displacements responsible for those stresses remains unknown. To better understand the limb motion within the socket, an inverse kinematic analysis was performed to estimate the motion between the socket and tibia for 10 individuals with a transtibial amputation performing walking and turning activities at 3 different speeds. The authors estimated the rotational stiffness of the limb-socket body to quantify the limb properties when coupled with the socket and highlight how this approach could help inform prosthetic prescriptions. Results showed that peak transverse displacement had a significant, linear relationship with peak transverse loading. Stiffness of the limb-socket body varied significantly between individuals, activities (walking and turning), and speeds. These results suggest that transverse limb loading can serve as a surrogate for residual-limb shear stress and that the setup of a prosthesis could be individually tailored using standard motion capture and inverse kinematic analyses.

IMPROVEMENT AND PERFORMANCE EVALUATION OF A SYSTEM FOR MONITORING ROTATIONS AND DISPLACEMENTS OF BRIDGES BASED ON LASER POINTER AND DIGITAL PHOTOGRAMMETRY

A system for monitoring rotations and displacements of bridges based on laser pointer and digital photogrammetry is described. The system uses three common laser pointers and image processing. The inclination of the elastic line is measured by analysing the individual frames of an HD video of the laser beam footprint projected onto a flat target. The methodology, able to conjugate a high precision, low cost, and easiness of use, is an evolution of a method developed at University of Calabria, Italy. The use of three laser pointers allows to improve the performance of the previous method, obtaining both displacements and rotations at a generic point of the bridge deck, and deriving the transverse rotation of the deck cross section. The investigated method exploits the laser pointers’ property to provide a steady pointing direction, a long-range and a high-brightness visible imprint. The method and the results of an experimental test are described and discussed.

Hindfoot Alignment Changes after Internal Fixation of Distal Tibial Fracture: Comparing Radiological and Clinical Outcomes of Patients Treated with Standard Plating vs Intramedullary Nailing

Category: Trauma Introduction/Purpose: Until now, many papers Traditionally concerned for union of the fracture, changes of alignment, clinical symptoms and complication. However, there are no studies on changes in foot alignment, hid foot and related clinical changes. The Purpose of this study to evaluate clinical outcome and radiological outcome including hind foot alignment using Plate versus IM nail fixation of distal tibia fracture and to evaluate influence factors of hindfoot alignment alteration among the radiologic parameters. Methods: Overall, 92 patients with distal tibial metaphyseal fractures (AO-OTA 43-A1, 43-A2) with simple or no articular involvement treated from 2002 to 2013. Among them, 39 cases of intramedullary nailing and 53 cases of standard plate osteosynthesis were performed. Inclusion criteria were applied for patient group. Union rate and complication rate compared both group. Radiographic measurements were evaluated at a minimum of 1-year follow-up. Radiological parameters of hindfoot angulation and moment arm were measured at the Saltzman view, calcaneal pitch angle and Meary angle were measured at the lateral standing radiograph. Hindfoot alignment changes after surgery were compared between both groups using student T-test. Alignment changes after fracture site union were evaluated simple radiograph and computed radiograph; coronal plane angulation, saggital plane angulation and transverse plane rotation were measured. Correlation and regression were analyzed between fracture alignment parameters and hindfoot alignment Results: We studied 92 patients with distal tibia fractures treated with IMN (39 patients) and SP (53 patients). 37 patients in the IMN group and 47 in the IMN group met inclusion criteria. All patients ultimately healed, with the average time to union of 26 weeks in both the groups. Complications were similar between the two groups. Hindfoot alignment angle, calcaneal pitch and Mearly angles showed no difference between the groups. But moment arm was increased valgus in the IMN group. Angulation at fracture site on the coronal and hindfoot alignment changes were showed low significant relationship(R=0.38). But transverse rotation and hindfoot alignment changes were showed high significant relationship(R=0.79). And only transverse rotation has a strong correlation with hindfoot alignment changes after regression analysis. Conclusion: Similar union rate and complication were seen when treating nonarticular metaphyseal distal tibia fractures with SP compared with IMN. Angulation on coronal plane after internal fixation may a little affect to change hindfoot alignment due to compensation on the subtalar joint. However, rotation on the transverse plane has intactly influenced hindfoot alignment alteration. Therefore, regardless of the fixed method, the patients treated distal tibial fracture required close attention to changes in hindfoot alignment due to transverse rotation during surgery.