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Background To investigate the effect of different fixation strategies of the intramedullary interlocking nail (IIN) on the mechanical behavior of a polymeric implant applied for femoral fracture fixation in calves, and to evaluate the performance of a glass fiber-reinforced polymer applied in a bovine femoral fracture reduction system, five Holstein male animals with a mean weight (±SD) of 62.8 ± 20.4 kg and aged 74 ± 15 were used to generate biomechanical parameters for this study. Twelve models of the fractured bovine femur, simulating a simple oblique fracture, were developed for use during the simulations. The models were divided into three groups, with each group of four models being associated with a different fixation strategy. Models were used to simulate the loading conditions corresponding to a calf in the transition (decubitus position to static position) condition. The maximum stresses found in each set (bone/implant) were compared with the reference stresses of each nail material. Results Maximum implant stresses were found in the screws and at the interface between the screw and the nail. The performance of implants was influenced by the material and fixation strategy, which can be confirmed by the stress values found in the set. The analysis indicated that the composite nail is able to withstand the loading demands in all fixation strategies. Conclusions The finite element analysis (FEA) demonstrated that all polymeric materials analyzed provided sufficient resistance to withstand the loading forces imposed to the femur when an adequate blocking strategy was applied.

Pedaling asymmetry is claimed as a factor of influence on injury and performance. However, the evidence is still controversial. Most previous studies determined peak torque asymmetries, which in our understanding does not consider the pattern of movement like torque profiles. Here we demonstrate that asymmetries in pedaling torque at different exercise intensities can be better described when the torque profiles are considered using functional analysis of variance than when only the peak values are analyzed. We compared peak torques and torque curves recorded while cyclists pedaled at submaximal intensities of 60%, 80%, and 95% of the maximal power output and compared data between the preferred and non-preferred legs. ANOVA showed symmetry or rather no difference in the amount of peak torque between legs, regardless of pedaling intensity. FANOVA, on the other hand, revealed significant asymmetries between legs, regardless of cycling intensity, apparently for different sections of the cycle, however, not for peak torque, either. We conclude that pedaling asymmetry cannot be quantified solely by peak torques and considering the analysis of the entire movement cycle can more accurately reflect the biomechanical movement pattern. Therefore, FANOVA data analysis could be an alternative to identify asymmetries. A novel approach as described here might be useful when combining kinetics assessment with other approaches like EMG and kinematics and help to better understand the role of pedaling asymmetries for performance and injury risks.

Asymmetries compromise performance in powerlifting and Paralympic powerlifting, but its quantification can be complex. Previous studies consider average or peak values to quantify asymmetries, however this approach does not consider the pattern of movement like velocity profiles. Here we demonstrate that conducting a functional analysis of variance (FANOVA) permits to quantify asymmetries in bench press performance by Paralympic powerlifting at different submaximal intensities. Kinematic data were collected from 10 Paralympic powerlifting athletes performing in bench press at submaximal intensities (50% and 90% of the one-repetition maximum). Linear velocity was quantified considering mean values and the entire waveform. Mean values were compared by analysis of variance (ANOVA) and the waveforms were compared by FANOVA. FANOVA identified asymmetry profiles that ANOVA did not recognize at the highest intensity, which is the closest to a competition. This way, FANOVA can bring advantages to the analysis of competitive performance. FANOVA data analysis identifies asymmetries at higher intensity of effort considering the whole pattern of movement. Therefore, we consider that the FANOVA's approach may benefit the biomechanical assessment of the Paralympic powerlifting.

Treatment of long bone fractures in bovines has been an objective of recent veterinary research. Accurate estimates of body segment inertial parameters (BSIP) play an important role in an appropriate prosthesis development. The aim of the present study is to develop a geometric model of bovine pelvic limb based on the mass distribution properties. Computer tomography images were used to obtain a computational model of bovine limb. This model provided information for geometric model construction. Measures of segmental mass, positions of segmental center of mass (CoM), and longitudinal moment of inertia (MoI zz ) of segments of the right pelvic limb were estimated based on the geometric model. These estimates were compared with the computational model’s measurements and showed consistent accuracy. The segment mass decreased with distance from the pelvis with mean relative error (Er) less than −5.87 ± 1.2%, as did the segment MoI zz with Er(%) less than −16.40 ± 7.61% for segments predominantly consisting of bony tissue. The MoI zz was overestimated for segment with more soft tissue with Er(%) = 10.95 ± 19.08. The CoM zz was located 36–50% distal to the proximal segment end. The more proximal segment showed the largest Er(%) = −11.21 ± 2.41%, while the more distal showed the smallest Er(%) = 1.82 ± 0.87% for CoM zz . This study not only presents a technique that may be applied to other body segments, but also provides insight into bovine musculoskeletal system necessary to improve the biomechanical models applied to dynamic analysis of bovine movement.