Search results for "Biomechanic"

Stability of the upper neck during isometric neck exercises in rheumatoid arthritis patients with atlantoaxial disorders.

2008

To study the effect of isometric neck strength exercises on upper cervical stability in patients with rheumatoid arthritis (RA).Twenty patients with a mean (SD) age of 58 (9) years and duration of RA of 27 (10) years volunteered for the study. Lateral radiographs of the cervical spine were taken to measure the current atlantoaxial distance (AAD) in flexion and extension. Maximal isometric neck flexion and extension strength values were measured by a dynamometer. Thereafter, AADs were measured from radiographs taken at 80-90% resistance of maximal strength.According to the full flexion radiographs at baseline, the patients were classified into three groups: eight patients without anterior at…

Kinematic parameters after tibial nonunion treatment using the Ilizarov method

2021

Abstract Background Analysis of the outcomes of Ilizarov treatment of tibial nonunion shows functional deficits in the lower limbs of some patients. Biomechanical gait parameters are an important measure for assessing musculoskeletal disorder treatments that aim to restore normal gait. The purpose of our study was to compare the kinematic parameters in patients with tibial nonunion treated using the Ilizarov method and those in a control group of healthy volunteers. Methods The study population consisted of 23 patients (age 54.9 ± 16.4 years) who were treated for tibial nonunion using the Ilizarov method, as well as 22 healthy adult controls (age 52.7 ± 10.6 years). Kinematic parameters wer…

Human voice pitch measures are robust across a variety of speech recordings: methodological and theoretical implications

2021

Fundamental frequency ( f o ), perceived as voice pitch, is the most sexually dimorphic, perceptually salient and intensively studied voice parameter in human nonverbal communication. Thousands of studies have linked human f o to biological and social speaker traits and life outcomes, from reproductive to economic. Critically, researchers have used myriad speech stimuli to measure f o and infer its functional relevance, from individual vowels to longer bouts of spontaneous speech. Here, we acoustically analysed f o in nearly 1000 affectively neutral speech utterances (vowels, words, counting, greetings, read paragraphs and free spontaneous speech) produced by the same 154 men and women, ag…

Acute effect of induced asymmetrical running technique on foot skin temperature

2020

The aim of the study was to evaluate skin temperature of the soles of the feet before and after a provoked asymmetrical running. Seventeen recreational male runners performed two 15 min running tests in the same session. In the first test, participants performed running without modifying their running technique (control condition). In the second running test, they repeated the same protocol using an ankle weight of 1.5 kg in the non-dominant ankle (asymmetrical condition). Rate of perceive exertion, heart rate and spatio-temporal parameters were measured during the running tests. Skin temperature was measured with an infrared camera before and after each condition. Generally, comparing both…

Influence of the structural components of artificial turf systems on impact attenuation in amateur football players

2019

AbstractThe purpose of this research was to evaluate the influence of the structural components of different 3rd generation artificial turf football field systems on the biomechanical response of impact attenuation in amateur football players. A total of 12 amateur football players (24.3 ± 3.7 years, 73.5 ± 5.5 kg, 178.3 ± 4.1 cm and 13.7 ± 4.3 years of sport experience) were evaluated on three third generation artificial turf systems (ATS) with different structural components. ATS were composed of asphalt sub-base and 45 mm of fibre height with (ATS1) and without (ATS2) elastic layer or compacted granular sub-base, 60 mm of fibre height without elastic layer (ATS3). Two triaxial accelerome…

Assessment of tensile mechanical properties of the Achilles tendon in adult patients with haemophilic arthropathy.

2019

Symmetry function in gait pattern analysis in patients after unilateral transfemoral amputation using a mechanical or microprocessor prosthetic knee

2021

AbstractBackgroundAbove-knee amputations (AKAs) contribute to gait asymmetry. The level of asymmetry is affected by the type of knee prosthetic module. There is limited evidence suggesting that more technically advanced solutions (microprocessor modules; MicPK) are superior to less advanced ones (mechanical modules; MechPK). The study aimed to evaluate the variable range of hip and pelvic joint movements during gait and look for differentiating areas with an increased level of asymmetry of the gait cycle in individuals who underwent an AKA and are equipped with MicPK or MechPK.MethodsTwenty-eight individuals participated in the study; 14 were assigned to a study group of individuals who und…

Biomechanics of simulated versus natural cross-country sit skiing

2017

The purpose of this study was to investigate the biomechanics of cross-country sit-skiing in simulated and natural skiing. Thirteen international level athletes participated in a ski ergometer test (simulated conditions) and a test on snow in a ski-tunnel (natural conditions) using their personal sit-ski. Tests in both conditions were performed at individual maximal speed. When comparing the two conditions the main results were: (1) maximal speed in simulated conditions was lower (p < 0.05) but correlated well with the natural condition (r = 0.79, p < 0.001); (2) no differences in pole force variables were found; peak force (r = 0.77, p < 0.01) and average force (r = 0.78, p < 0.01) correla…

The location of the tibial accelerometer does influence impact acceleration parameters during running

2016

Tibial accelerations have been associated with a number of running injuries. However, studies attaching the tibial accelerometer on the proximal section are as numerous as those attaching the accelerometer on the distal section. This study aimed to investigate whether accelerometer location influences acceleration parameters commonly reported in running literature. To fulfil this purpose, 30 athletes ran at 2.22, 2.78 and 3.33 m · s–1 with three accelerometers attached with double-sided tape and tightened to the participants’ tolerance on the forehead, the proximal section of the tibia and the distal section of the tibia. Time-domain (peak acceleration, shock attenuation) and frequency-doma…

Effect of age in the ciliary muscle during accommodation: Sectorial analysis

2017

Abstract Purpose To compare changes in the ciliary muscle area at different sectors between pre-presbyopic and presbyopic eyes during accommodation by means of an anterior segment optical coherence tomographer (OCT). Methods The anterior ciliary muscle area was measured in 20 healthy and phakic pre-presbyopic eyes, whose mean age was 23.3 ± 4.4 years, and in 20 healthy and phakic presbyopic eyes, whose mean age was 46.5 ± 5.2 years. The relative change in the cross-sectional area of the ciliary muscle was measured at the nasal, inferior, and temporal sectors between 0 and −3 D of vergence, in −1 D step. A linear model was used to assess the correlation of each eye parameter with the accommo…