Due to the internal structure of the knee joint, the ability to characterize and quantify the dynamic response of the meniscal tissue directly in vivo is highly problematic. The main purpose of this study was to investigate the behaviour of the meniscus under loading conditions. Four healthy young females were included. To obtain T2* values in the meniscus, the vTE sequence was used with 10 echoes ranging from 0.8 to 10.1 ms. Submilisecond first echo time is a great advantage of vTE sequence allowing for precise mapping of relatively short T2*. The two-parametric least squares fitting procedure was used to calculate T2* pixel-wise. A custom-made diamagnetic apparatus was developed to simulate stress conditions on the lower limb in a conventional MR scanner. vTE T2* was performed in five consecutive scans, 6:10 min apart. Three different compartments of the medial and lateral meniscus were segmented. The differences at the different time-points were calculated. A constant increase of T2* times after compression was statistically significant in the anterior horn of the medial meniscus. T2* mapping with variable echo time sequence might be a satisfactorily sensitive technique to detect the changes of meniscus physiology under loading conditions in vivo.
- MeSH
- dospělí MeSH
- kloubní chrupavka * diagnostické zobrazování MeSH
- kolenní kloub MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- menisky tibiální * diagnostické zobrazování fyziologie MeSH
- zátěžový test * MeSH
- zobrazování trojrozměrné MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- kazuistiky MeSH
- práce podpořená grantem MeSH
Noninvasive imagining of the knee meniscus without the use of the contrast agents is more difficult compared to articular cartilage. Despite the lower signal intensity of the knee meniscus, MRI is considered the best non-invasive imaging method. Thanks to the lower water content in the meniscus compared to the surrounding tissues, it can be distinguished from the environment, but the determination of the boundaries is more complicated than in articular cartilage. There are many studies dealing with the MR imaging of the loaded and also unloaded knee, but they have mainly observed quantitative and geometric changes (movement or deformation of tissue), not targeted qualitative changes in the extracellular matrix (ECM). These changes can be evaluated with T2 relaxation times, which are more sensitive to the interaction of water molecules and the concentration of macromolecules and structures of the ECM, especially in the interaction based on the content, orientation and anisotropy of collagen fibers. Fluid and tissues with the higher water content level have long relaxation time T2. In the healthy meniscus these times are shorter; the reason is a highly organized structure of collagen and lower content of proteoglycans. To quantitatively detect changes, it is necessary to assure a sufficiently high resolution of images throughout choosing appropriate pulse sequences. After that, the acquired data can be processed to produce the T2 maps, to portray non-invasive collagen content, architecture of the ROI, changes in the water content (distribution of interstitial water in the solid matrix) and the spatial variation in depth. The aim of this work is firstly to introduce the meaning of T2 relaxation and methods for calculating T2 relaxation times. Further, the aim of this work is to give a brief description of the current pulse sequences used to display menisci.
- Klíčová slova
- T2 mapování, časově závislé změny laterálního při axiálním zatížení, manuální segmentace,
- MeSH
- experimenty na lidech MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody přístrojové vybavení využití MeSH
- menisky tibiální * anatomie a histologie fyziologie patologie MeSH
- muskuloskeletální systém anatomie a histologie patologie MeSH
- pilotní projekty MeSH
- statistika jako téma MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Knee cartilage and meniscus are living tissue, but have limited opportunities for growth and renewal. If they are not burdened for long time, there is a breach of metabolism in the deeper tissues. Many negative changes may be substantially eliminated by periodic various activities. Appropriate load (alternating medium intensity) stimulates the growth of cartilage and muscle and thus prevents them from wasting. When loads are occurring, with elastic deformation of cartilage synovial fluid is extruded from the matrix into the articular capsule slot and the density of the matrix grows. With removing load synovial fluid flows back into the cartilage. Given the intracharacteristics of the knee (spatial insufficiency) display changes directly inside the meniscus and cartilage is problematic. Detection and modeling of mechanical response of tissue structures to external mechanical loading is possible using non-invasive imaging methods. Fairly accurate representation with wide application in patients provides magnetic resonance imaging (MRI). MRI use is overwhelmingly performed in supine without burdening the limbs, which can lead to some extent misleading information, even though the unloaded cartilage is exposed to pressure induced by muscle tone. From the point of evaluating changes in knee cartilage to various long-lasting stress following publications are subject to literary critival review. The findings in this paper are obtained mainly on the study of avaliable literature. The authors use to evaluate changes different parameter setting of MRI and thus try to get the most detailed information about the observed structures in various specific types of loads.
- Klíčová slova
- degenerace, zátěž,
- MeSH
- chrupavka anatomie a histologie fyziologie patologie MeSH
- femur anatomie a histologie fyziologie patologie MeSH
- kolenní kloub anatomie a histologie fyziologie patologie MeSH
- koleno MeSH
- kyčelní kloub anatomie a histologie fyziologie patologie MeSH
- lidé MeSH
- ligamentum collaterale tibiale anatomie a histologie fyziologie patologie MeSH
- magnetická rezonanční tomografie metody přístrojové vybavení využití MeSH
- meniskus MeSH
- metaanalýza jako téma MeSH
- osteoartróza diagnóza komplikace MeSH
- statistika jako téma MeSH
- tělesná námaha fyziologie MeSH
- tibie anatomie a histologie fyziologie patologie MeSH
- Check Tag
- lidé MeSH
This work deals with verification of hypothesis based on the principle of hemispheric bilateral transfer by which it is possible to influence the activity of dominant upper extremity positively with right-handed people through aimed training of non-dominant upper extremity. On the basis of this hypothesis I suppose that shooting effectivity will increase and individual shooting abilities of upper right extremity will improve with right-handed players in basketball. By using specialized training aimed only at non-dominant left hand with the category of older girls between 14 and 15 years. Having used hand Tapping and Edinburgh questionnaire to determine laterality, the level of right/left-handedness was settled with every participant and a suitable group of 15 players was chosen from the results as an experimental group. There were only dominant right-handed players in every group. After performing complex of shooting tests from a spot in different positions, one group underwent 10 weeks training of non-dominant hand. After finishing it they performed the same battery of tests and the results were evaluated by non-parametric Wilcox pair test, t-test for pair values and by testing of two chosen percentage values the result were settled. By using the mentioned tests our hypothesis about transfer of handedness was not confirmed for transfer from non-dominant left hand to the dominant right one of the chosen age group. On the contrary it showed that training of non-dominant upper extremity had positive influence on improving shooting ability of left hand, which shows high effect of the process on non-dominant hand. When we look at statistic significance in comparison with the non-specialized group without special training our hypothesis was not confirmed even for non-dominant hand.
- Klíčová slova
- lateralita, měření rukovosti, měření mozkových hemisfér, mezihemisférický přenos informací, motorické učení,
- MeSH
- basketbal fyziologie MeSH
- dominance mozková fyziologie MeSH
- experimenty na lidech MeSH
- financování organizované MeSH
- funkční lateralita MeSH
- horní končetina fyziologie MeSH
- lidé MeSH
- metaanalýza jako téma MeSH
- mladiství MeSH
- motorické dovednosti MeSH
- motorické korové centrum MeSH
- mozek MeSH
- statistika jako téma MeSH
- tělesná výchova MeSH
- velký mozek fyziologie MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
