kinematics
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V práci jsou shrnuty nové poznatky o kinematice hlasivek, získané užitím vysokorychlostní kamery HSV. Standardně používané parametry hodnocení hlasivkové kinematiky jsou rozšířeny o nové, získané použitím metod, vycházejících z detekce hlasivkové štěrbiny a stanovení její hlavní osy. Na vybraných kazuistikách jsou dokumentovány parametry symetrie štěrbiny a pohybu těžiště hlasivkové štěrbiny vzhledem k její ose.
This study deals with new findings about vocal folds kinematics acquired by using High–Speed Video camera. The parameters usually applied to measuring vocal folds kinematics are supplemented with new ones which are based on detection of glottis and determination of its main axis. Parameters of glottis symmetry and parameters of motion of glottis center point against its main axis are illustrated on selected case reports.
INTRODUCTION The anterior cruciate ligament (ACL) reconstruction is a tried and tested method in treating knee joint instability which brings valuable results in an acceptable time frame. In the long-term follow-up, however, a higher risk of knee osteoarthritis development is described. One of the possible reasons is considered to be the abnormal kinematics of the operated knee. The purpose of our study was to determine the degree to which the ACL reconstruction helps restore the correct gait cycle compared to the healthy limb. MATERIAL AND METHODS The study included patients after the ACL reconstruction performed in the period from 1 January 2016 to 31 March 2018. With the use of strict criteria, 11 patients were selected for kinematic analysis, who underwent examinations in a gait laboratory and were also evaluated using the Tegner and Lysholm rating systems and the IKDC (International Knee Documentation Committee) knee score, namely preoperatively and at 6 and 12 months postoperatively. The kinematic assessment of gait was carried out using the Vicon MX system with the placement of reflexive markers in line with the Plug-In Gait model. RESULTS The clinical outcomes (namely the score according to Tegner, Lysholm as well as the IKDC) during the first year postoperatively showed a major improvement in knee function and the achievement of the pre-injury activity level. The kinematic analysis revealed lower knee extension at the stance phase and lower overall range of motion of the limb with the injured ACL compared to the healthy limb. The follow-up evaluation at 6 and 12 months postoperatively showed a persisting between-limbs difference in knee extension, whereas the range of motion gradually improved during the year. CONCLUSIONS Although our study confirmed that the ACL reconstruction is an efficient method to treat knee joint instability, it also indicated that even at one year after the ACL reconstruction, the kinematics of the operated knee was not fully restored to the level of the heathy knee. The persisting limb-difference in gait kinematics could contribute to the gradual development of degenerative changes in the operated knee joint. Key words: anterior cruciate ligament deficiency, anterior cruciate ligament reconstruction, knee kinematics during gait, knee osteoarthritis.
Kinematika pohybového aparátu závisí na funkčním stavu jeho jednotlivých složek, především tedy kloubů a kosterních svalů. V příspěvku jsou uvedeny výsledky pilotní studie, provedené u mladých běžců. Probandi byli nejprve vyšetřeni metodami manuální medicíny se zaměřením na oblast pánve, kloubů a svalů dolních končetin. Poté byl pořízen 30 záznam společně s videozáznamem jejich běhu. U většiny probandů byla zjištěna dysfunkce kyčelního, kolenního či hlezenního kloubu. Tato dysfunkce může mít strukturální nebo funkční příčinu. U funkční poruchy byla provedena cílená intervence. Poté byli probandi znovu vyšetřeni manuálně i pomocí 30- analýzy pohybu. Porovnáním záznamu 30- analýzy běhu s výsledky manuálního vyšetření byl ověřen vliv funkčního stavu těchto kloubů na kinematiku běhu.
Kinematics of the locomotor system depends on functional state of each component, especially of joints and skeletal muscles. We describe in this paper a pilot study in young runners. Simultaneously 30 record and videorecord of their running and manual examination of the pelvis, big joints and relevant muscles of the lower extremities was provided. In the most of cases a dysfunction of the hip, the knee or the ankle joint was found. The dysfunction can be structural or functional. In case of functional disorder necessary intervention was made. Then the manual examination and the 30- motion analysis was provided again. Comparison of the 30- analysis record and the manual examination revealed that kinematics of running is affected with functional state of these joints.
- Klíčová slova
- kinematika,
- MeSH
- běh MeSH
- dolní končetina MeSH
- Publikační typ
- abstrakt z konference MeSH
Acta orthopaedica Scandinavica, ISSN 0300-8827 suppl. no. 299, vol. 72, February 2001
52 s. : il., tab. ; 24 cm
This article deals with an experimental work on spinal segment kinematics. A structure a unique mechanism for spinal segment loading is described. This mechanism can perform periodic loading by pure bending (flexion/extension) or by coupled bending, shear and compression. The kinematics of particular vertebra is measured by means of motion capture technique. In this case, a commercial system Qualisys was used. The raw results are time sequences of marker’s coordinates corresponding to moving bodies (vertebra). These data are post processed in a Matlab software and converted to more readable kinematic description using instantaneous axis (or center in 2D) of rotation. These experimental data will be used for numerical determination of load transition ratios between two adjacent vertebras.
- Klíčová slova
- helikální osy, měření optickou metodou, kinematika,
- MeSH
- artroplastika meziobratlové ploténky metody trendy využití MeSH
- biomechanika MeSH
- bolesti zad chirurgie MeSH
- financování organizované MeSH
- modely u zvířat MeSH
- páteř fyziologie patofyziologie patologie MeSH
- pohyb fyziologie MeSH
- prasata MeSH
- rotace škodlivé účinky MeSH
- statistika jako téma MeSH
- tělesná námaha fyziologie MeSH
- torze mechanická MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
BACKGROUND: Sensorimotor foot orthoses is an alternative concept, which in addition to mechanical effects, are designed to change muscle activation by altering sensory input to the plantar surface of the foot. However, there is little evidence of how these affect the kinematics of the foot during gait. RESEARCH QUESTION: The aim of the study was to explore the immediate effect of calcaneal medial heel bars and retrocapital bars on foot kinematics during the stance phase of gait. METHODS: Kinematic data were collected from 32 healthy individuals using an eight camera motion capture system and a six-degrees-of-freedom multi-segment foot model in three different orthotic conditions; calcaneal medial heel bar, retrocapital bar, and no orthosis. Vector field statistical analysis was performed to explore the effect of the orthotic conditions over the kinematic time series curves during stance phase. Peak median and interquartile ranges were also reported during the different phases of stance. RESULTS: The calcaneal medial bar significantly decreased rearfoot eversion for the majority of the stance phase and compensatory increased midfoot eversion during the entire stance phase compared to the no orthosis condition. The retrocapital bar rotated the foot externally significantly abducting the rearfoot for the entire stance phase and the midfoot for the majority of stance phase. SIGNIFICANCE: The calcaneal medial heel bar and retrocapital bar significantly altered the foot kinematics in a way that may benefit patients with abnormal pronation and intoeing gait.
The alteration in mechanical properties of posterior pelvis ligaments may cause a biased pelvis deformation which, in turn, may contribute to hip and spine instability and malfunction. Here, the effect of different mechanical properties of ligaments on lumbopelvic deformation is analyzed via the finite element method. First, the improved finite element model was validated using experimental data from previous studies and then used to calculate the sensitivity of lumbopelvic deformation to changes in ligament mechanical properties, load magnitude, and unilateral ligament resection. The deformation of the lumbopelvic complex relative to a given load was predominant in the medial plane. The effect of unilateral resection on deformation appeared to be counterintuitive, suggesting that ligaments have the ability to redistribute load and that they play an important role in the mechanics of the lumbopelvic complex.
Cílem studie bylo pomocí 3D kinematické analýzy stanovit vliv osteotomie tibie na změnu kinematických parametrů chůze u pacientů s unilaterální artrózou kolenního kloubu. Výzkumný soubor tvořily 4 ženy a 4 muži (průměrný věk 52,3±7,3 let, hmotnost 99,1±14,8 kg, výška 174,3±10,8 cm). Měření proběhlo před operací a následně 6-10 měsíců po operaci s využitím optoelektronického systému Vicon MX. Pro označení bodů na dolních končetinách a pánvi byl použit model PlugInGait. Pro určení jednotlivých fází krokového cyklu byly použity tenzometrické plošiny Kistler 9286AA. Výsledky studie dokazují příznivý vliv osteotomie tibie na stereotyp a kvalitu chůze u pacientů s gonartrózou. Po operaci došlo k prodloužení délky kroku a dvojkroku. Dále se upravila míra rotace kolenního kloubu, kompenzační zvýšení rozsahu pohybu pánve do anteverze a retroverze se normalizovalo.
The aim of the study was to determine the effect of tibial osteotomy on the change of kinematic gait parameters in patients with unilateral arthrosis of the knee using 3D kinematic analysis. The research group consisted of 4 women and 4 men (mean age 52.3 ± 7.3 years, weight 99.1 ± 14.8 kg, height 174.3 ± 10.8 cm). Measurement was taken before and then 6 to 10 months after the surgery by using the Vicon MX optoelectronic system. The PlugInGait model was used to mark the points on the lower limbs and pelvis. Kistler 9286AA force plates were used to determine the individual phases of the step cycle. The results of the study demonstrate the beneficial effect of tibial osteotomy on stereotype and gait quality in patients with knee arthritis. After the surgery, step length and stride length were extended. Furthermore, the knee rotation was adjusted and the increased anteversion and retroversion of pelvis were normalized.
- Klíčová slova
- systém Vicon,
- MeSH
- analýza chůze * metody MeSH
- artróza kolenních kloubů chirurgie komplikace MeSH
- biomechanika MeSH
- dospělí MeSH
- kineziologie aplikovaná MeSH
- lidé středního věku MeSH
- lidé MeSH
- osteotomie metody MeSH
- pilotní projekty MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
První vysoce přesná 3D kinematická data pánevních končetin zaznamenaná u normálních psů čtyř různých plemen (bígl, francouzský buldoček, malinois, vipet) in vivo pomocí biplanární vysokofrekvenční fluoroskopie v kombinaci s 3D optoelektrickým systémem a následnou analýzou XROMM bez použití markerů (Scientific Rotoscoping, SR nebo 3D-2D registrační proces) odhalují: a) 3D kinematiku pánevních končetin v dosud nevídané míře přesnosti; b) podstatná omezení při použití dat založených na kožních markerech. Očekávali jsme, že kinematika pánevních končetin se bude lišit v závislosti na tvaru těla. Srovnání čtyř plemen odlišuje francouzského buldočka od ostatních, pokud jde o trajektorie ve frontální rovině (abdukce/addukce) a rotaci stehenní kosti v dlouhé ose. Francouzští buldočci převádějí rozsáhlou rotaci dlouhé osy femuru (> 30°) do silného laterálního posunu a rotace kolem kraniokaudální osy (rolování) a distálně-proximální osy pánve (odklon), aby kompenzovali silně abdukované postavení pánevních končetin od začátku stoje. Předpokládáme, že plemena, která vykazují neobvyklou kinematiku, zejména vysokou abdukci femuru, mohou být náchylná k vyššímu dlouhodobému zatížení křížových vazů.
The first high-precision 3D in vivo hindlimb kinematic data to be recorded in normal dogs of four different breeds (Beagle, French bulldog, Malinois, Whippet) using biplanar, high-frequency fluoroscopy combined with a 3D optoelectric system followed by a markerless XROMM analysis (Scientific Rotoscoping, SR or 3D-2D registration process) reveal a) 3D hindlimb kinematics to an unprecedented degree of precision and b) substantial limitations to the use of skin marker -based data. We expected hindlimb kinematics to differ in relation to body shape. But, a comparison of the four breeds sets the French bulldog aside from the others in terms of trajectories in the frontal plane (abduction/adduction) and long axis rotation of the femur. French bulldogs translate extensive femoral long axis rotation (>30°) into a strong lateral displacement and rotations about the craniocaudal (roll) and the distalproximal (yaw) axes of the pelvis in order to compensate for a highly abducted hindlimb position from the beginning of stance. We assume that breeds which exhibit unusual kinematics, especially high femoral abduction, might be susceptible to a higher long-term loading of the cruciate ligaments.
- MeSH
- analýza dat MeSH
- biomechanika * fyziologie MeSH
- končetiny * MeSH
- psi klasifikace MeSH
- zvířata MeSH
- Check Tag
- psi klasifikace MeSH
- zvířata MeSH
- Publikační typ
- abstrakty MeSH
Accurate assessment of 3D tibio-femoral kinematics is essential for understanding knee joint functionality, but also provides a basis for assessing joint pathologies and the efficacy of musculoskeletal interventions. Until now, however, the assessment of functional kinematics in healthy knees has been mostly restricted to the loaded stance phase of gait, and level walking only, but the most critical conditions for the surrounding soft tissues are known to occur during high-flexion activities. This study aimed to determine the ranges of tibio-femoral rotation and condylar translation as well as provide evidence on the location of the centre of rotation during multiple complete cycles of different gait activities. Based on radiographic images captured using moving fluoroscopy in ten healthy subjects during multiple cycles of level walking, downhill walking and stair descent, 3D femoral and tibial poses were reconstructed to provide a comprehensive description of tibio-femoral kinematics. Despite a significant increase in joint flexion, the condylar antero-posterior range of motion remained comparable across all activities, with mean translations of 6.3-8.3 mm and 7.3-9.3 mm for the medial and lateral condyles respectively. Only the swing phase of level walking and stair descent exhibited a significantly greater range of motion for the lateral over the medial compartment. Although intra-subject variability was low, considerable differences in joint kinematics were observed between subjects. The observed subject-specific movement patterns indicate that accurate assessment of individual pre-operative kinematics together with individual implant selection and/or surgical implantation decisions might be necessary before further improvement to joint replacement outcome can be achieved.
- MeSH
- biomechanika MeSH
- chůze (způsob) MeSH
- femur * diagnostické zobrazování MeSH
- kolenní kloub * MeSH
- lidé MeSH
- rozsah kloubních pohybů MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH