Search results for "ADULT"
showing 10 items of 17453 documents
EMG-Assisted Muscle Force Driven Finite Element Model of the Knee Joint with Fibril-Reinforced Poroelastic Cartilages and Menisci.
2019
Abnormal mechanical loading is essential in the onset and progression of knee osteoarthritis. Combined musculoskeletal (MS) and finite element (FE) modeling is a typical method to estimate load distribution and tissue responses in the knee joint. However, earlier combined models mostly utilize static-optimization based MS models and muscle force driven FE models typically use elastic materials for soft tissues or analyze specific time points of gait. Therefore, here we develop an electromyography-assisted muscle force driven FE model with fibril-reinforced poro(visco)elastic cartilages and menisci to analyze knee joint loading during the stance phase of gait. Moreover, since ligament pre-st…
Magnetic resonance chondro-crassometry (MR CCM): a method for accurate determination of articular cartilage thickness?
1996
A method for the assessment of articular cartilage thickness based on MRI is presented and its accuracy and reproducibility tested. Six specimens of human patellae were imaged, using a fat-suppressed FLASH 3D sequence, and sectioned with a high-precision band saw. The regional distribution of articular cartilage thickness was determined from the MR images and from the anatomical sections (intervals of 0.5 mm). With image analysis 50-90% of the image points were found to lie within exactly the same thickness interval in corresponding patterns, and less than 17% deviated more than 0.5 mm. More than 85% of all pixels were reproducible with MRI after new positioning of the joint. No influence o…
Repeatability of patellar cartilage thickness patterns in the living, using a fat-suppressed magnetic resonance imaging sequence with short acquisiti…
1998
A fast, reproducible, and noninvasive method is required for quantifying cartilage thickness clinically and for studying the deformation of articular cartilage during and after mechanical loading in vivo. The objective of the current investigation was to test the repeatability of regional distribution patterns of patellar cartilage thickness in the living on the basis of a fat-suppressed magnetic resonance imaging sequence with a short acquisition time and three-dimensional digital data processing. The knees of eight healthy volunteers were transversally imaged with a fat-suppressed FLASH-3D (fast low angle shot) sequence (acquisition time: 4 minutes and 10 seconds). In each case, the joint…
Traumatic damage to the cartilage influences outcome of anatomically reduced acetabular fractures: A medium-term retrospective analysis
2011
We reviewed 77 patients with an acetabular fracture, treated operatively through a non-extensile approach after an average time of 45 months. The ilioinguinal approach was chosen in 41, the Kocher-Langenbeck approach in 36 patients. Following the Letournel classification, the most frequent lesions were posterior wall (26%), two-column (22.1%) and anterior column (14.3%) fractures. Subchondral impaction, intra-articular fracture fragments and fracture comminution, called modifiers, could be identified in the preoperative CT-data of 38 patients (49.4%). Patients were operated after an average of 4 days. Average hospital stay was 19 days. Sciatic nerve and peroneal nerve palsy were registered …
Determination of knee joint cartilage thickness using three-dimensional magnetic resonance chondro-crassometry (3D MR-CCM)
1996
The objective of this article was to analyze the accuracy and precision with which the quantitative distribution of articular cartilage can be determined in the knee joint using MRI. A three-dimensional (3D) technique that accounts for the out-of-plane deviation of the interface normal in strongly curved joint surfaces (3D MR-CCM) has been developed for cartilage thickness measurements. Eight cadaveric knee-joint specimens and six volunteers were imaged using a fat-suppressed gradient-echo sequence at a resolution of 2 x 0.31 x 0.31 mm3. Cartilage volumes and topographical thickness maps were obtained and compared with those derived from anatomical sections by image analysis. The deviation …
Importance of Patella, Quadriceps Forces, and Depthwise Cartilage Structure on Knee Joint Motion and Cartilage Response During Gait
2015
In finite-element (FE) models of the knee joint, patella is often omitted. We investigated the importance of patella and quadriceps forces on the knee joint motion by creating an FE model of the subject's knee. In addition, depthwise strains and stresses in patellar cartilage with different tissue properties were determined. An FE model was created from subject's magnetic resonance images. Knee rotations, moments, and translational forces during gait were recorded in a motion laboratory and used as an input for the model. Three material models were implemented into the patellar cartilage: (1) homogeneous model, (2) inhomogeneous (arcadelike fibrils), and (3) random fibrils at the superficia…
Non-invasive determination of cartilage thickness throughout joint surfaces using magnetic resonance imaging.
1997
Abstract Data on articular cartilage thickness in the living are important for the design of computer models, aimed at preoperatively assessing the effect of surgical procedures on joint contact and load transmission, and for the calculation of cartilage material properties from its deformational behavior as determined during arthroscopy. A non-invasive method for measuring cartilage thickness in living subjects is, however, not available. A technique based on magnetic resonance imaging has therefore been tested for assessing articular cartilage thickness throughout joint surfaces. The accuracy is determined by comparing cartilage thickness maps obtained from three patellar specimens with a…
Protein aggregation in congenital myopathies.
2011
Protein aggregation in congenital myopathies may be encountered among different myofibrillar myopathies such as granulofilamentous myopathy, cytoplasmic body myopathy, or spheroid body myopathy, which are designated as αB crystallinopathy, desminopathy, and myotilinopathy, respectively, according to the respective mutant proteins. Caps in cap disease and reducing bodies in reducing body myopathy were disclosed to contain numerous proteins. The multitude of diverse proteins aggregating within muscle fibers suggests impaired extralysosomal degradation of proteins, a disturbance of catabolism. The lack of different proteins accruing, but the mutant ones at an early age of affected patients in …
Local anaesthetic sympathetic blockade for complex regional pain syndrome
2016
This is the peer reviewed version of the following article: The Cochrane database of systematic reviews, which has been published in final form at https://doi.org/10.1002/14651858.CD004598.pub4. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Background: This review is an update of a previously published review in the Cochrane Database of Systematic Reviews, 2005, Issue 4 (and last updated in the Cochrane Database of Systematic Reviews, 2013 issue 8), on local anaesthetic blockade (LASB) of the sympathetic chain to treat people with complex regional pain syndrome (CRPS). Objectives: To assess the efficacy of LASB for the…
Thoracic spinal cord cavernous angioma: a case report and review of the literature
2014
Introduction: Cavernous angiomas of the spinal cord are rare vascular malformations, which account for approximately 5 to 12 percent of spinal cord vascular lesions. They usually originate in the vertebrae, with occasional extension into the extradural space, and intramedullary cavernomas, even if reported in the literature, are very rare. Case presentation: We report the case of a 34-year-old Caucasian woman affected by a thoracic intramedullary cavernous angioma. Our patient complained of 10-day history of acute dorsal pain, progressive weakness of both lower extremities, worse on the right side, a ‘pins and needles’ sensation in the abdominal region and bladder dysfunction. Magnetic reso…