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José M. Vázquez - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Open Access Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
2016Co-Authors: Alberto Arencibia, Mario Encinoso, Daniel Morales, José Raduan Jaber, Diego Blanco, Ro Artiles, José M. VázquezAbstract:Background: The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger (Panthera tigris) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images. Results: MR images showed the bone, articular cartilage, menisci and ligaments of the normal tiger Stifle. SE T1-weighted sequence provided excellent resolution of the subchondral bones of the femur, tibia and patella compared with the GE STIR T2-weighted MR images. Articular cartilage and synovial fluid were visualised with high signal intensity in GE STIR T2-weighted sequence, compared with SE T1-weighted sequence where they appeared with intermediate intensity signal. Menisci and ligaments of the Stifle Joint were visible with low signal intensity in both sequences. The infrapatellar fat pad was hyperintense on SE T1-weighted images and showed low signal intensity on GE STIR T2-weighted images. Conclusions: MRI provided adequate information of the bony and soft tissues structures of Bengal tiger Stifle Joints. This information can be used as initial anatomic reference for interpretation of MR Stifle images and to assist in the diagnosis of diseases of this region
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Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
BMC Veterinary Research, 2015Co-Authors: Alberto Arencibia, Mario Encinoso, Alejandro Artiles, Daniel Morales, José Raduan Jaber, Diego Blanco, José M. VázquezAbstract:Background The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger (Panthera tigris) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images.
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Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
BMC Veterinary Research, 2015Co-Authors: Alberto Arencibia, Mario Encinoso, Alejandro Artiles, Daniel Morales, José Raduan Jaber, Diego Blanco, José M. VázquezAbstract:Background The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger ( Panthera tigris ) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images. Results MR images showed the bone, articular cartilage, menisci and ligaments of the normal tiger Stifle. SE T1-weighted sequence provided excellent resolution of the subchondral bones of the femur, tibia and patella compared with the GE STIR T2-weighted MR images. Articular cartilage and synovial fluid were visualised with high signal intensity in GE STIR T2-weighted sequence, compared with SE T1-weighted sequence where they appeared with intermediate intensity signal. Menisci and ligaments of the Stifle Joint were visible with low signal intensity in both sequences. The infrapatellar fat pad was hyperintense on SE T1-weighted images and showed low signal intensity on GE STIR T2-weighted images. Conclusions MRI provided adequate information of the bony and soft tissues structures of Bengal tiger Stifle Joints. This information can be used as initial anatomic reference for interpretation of MR Stifle images and to assist in the diagnosis of diseases of this region.
D. S. Simpson - One of the best experts on this subject based on the ideXlab platform.
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The Effect of Total Meniscectomy versus Caudal Pole Hemimeniscectomy on the Stifle Joint of the Sheep
VCOT Archive, 1999Co-Authors: D. S. Simpson, Christopher R. Bellenger, Peter Ghosh, Y. Numata, Christopher B. LittleAbstract:The effect of total medial meniscectomy versus caudal pole hemimeniscectomy on the Stifle Joint of sheep was studied experimentally. Six months after the operations gross pathology, histopathology, cartilage biochemical analysis and the rate of proteoglycan synthesis in tissue culture were used to compare the articular cartilage harvested from the meniscectomised Joints. Degeneration of the articular cartilage from the medial compartment of the Joints was present in both of the groups. Caudal pole hemimeniscectomy induces a comparable degree of articular cartilage degeneration to total medial meniscectomy in the sheep Stifle Joint.
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The Effect of Total Meniscectomy versus Caudal Pole Hemimeniscectomy on the Stifle Joint of the Sheep
Veterinary and Comparative Orthopaedics and Traumatology, 1999Co-Authors: Christopher R. Bellenger, Peter Ghosh, Y. Numata, C. Little, D. S. SimpsonAbstract:SummaryTotal medial meniscectomy and caudal pole hemimeniscectomy were performed on the Stifle Joints of twelve sheep. The two forms of meniscectomy produced a comparable degree of postoperative lameness that resolved within two weeks of the operations. After six months the sheep were euthanatised and the Stifle Joints examined. Fibrous tissue that replaced the excised meniscus in the total meniscectomy group did not cover as much of the medial tibial condyle as the residual cranial pole and caudal fibrous tissue observed following hemimeniscectomy. The articular cartilage from different regions within the Joints was examined for gross and histological evidence of degeneration. Analyses of the articular cartilage for water content, glycosaminoglycan composition and DNA content were performed. The proteoglycan synthesis and release from explanted articular cartilage samples in tissue culture were also measured. There were significant pathological changes in the medial compartment of all meniscectomised Joints. The degree of articular cartilage degeneration that was observed following total meniscectomy and caudal pole meniscectomy was similar. Caudal pole hemimeniscectomy, involving transection of the meniscus, causes the same degree of degeneration of the Stifle Joint that occurs following total meniscectomy.The effect of total medial meniscectomy versus caudal pole hemimeniscectomy on the Stifle Joint of sheep was studied experimentally. Six months after the operations gross pathology, histopathology, cartilage biochemical analysis and the rate of proteoglycan synthesis in tissue culture were used to compare the articular cartilage harvested from the meniscectomised Joints. Degeneration of the articular cartilage from the medial compartment of the Joints was present in both of the groups. Caudal pole hemimeniscectomy induces a comparable degree of articular cartilage degeneration to total medial meniscectomy in the sheep Stifle Joint.
Nigel G. Shrive - One of the best experts on this subject based on the ideXlab platform.
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Ligament and meniscus loading in the ovine Stifle Joint during normal gait
The Knee, 2016Co-Authors: Joshua M. Rosvold, Cyril B. Frank, Mohammad Atarod, Bryan J. Heard, E. J. O. O'brien, Nigel G. ShriveAbstract:Abstract Background The ovine Stifle Joint is an ideal preclinical model to study knee Joint biomechanics. Knowledge of the ovine ligamentous and meniscal loading during normal gait is currently limited. Methods The in vivo kinematics of the ovine Stifle Joint (N=4) were measured during "normal" gait using a highly accurate instrumented spatial linkage (ISL, 0.3±0.2mm). These motions were reproduced in vitro using a unique robotic testing platform and the loads carried by the anterior/posterior cruciate ligaments (ACL/PCL), medial/lateral collateral ligaments (MCL/LCL), and medial/lateral menisci (MM/LM) during gait were determined. Results Considerable inter-subject variability in tissue loads was observed. The load in the ACL was near zero at hoof-strike (0% gait) and reached a peak (100 to 300N) during early-stance (~10% gait). The PCL reached a peak load (200 to 500N) just after hoof-strike (~5% gait) and was mostly unloaded throughout the remainder of stance. Load in the MCL was substantially lower than the cruciate ligaments, reaching a maximum of 50 to 100N near the beginning of stance. The LCL carried a negligible amount of load through the entire gait cycle. There was also a major contribution of the MM and LM to load transfer from the femur to the tibia during normal gait. The total meniscal load reached a maximum average between 350 and 550N during gait. Conclusion Knowledge of Joint function during normal motion is essential for understanding normal and pathologic Joint states. The considerable variability in the magnitudes and patterns of tissue loads among animals simulates clinical variability in humans. Level of evidence III.
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long term in vivo kinematics of the ovine Stifle Joint following anterior cruciate ligament transection
Journal of Undergraduate Research in Alberta, 2015Co-Authors: Jessica Norman, Mohammad Atarod, Bryan J. Heard, Kristen I Barton, Mehdi Shekarforoush, John L Sevick, Yamini Achari, Nigel G. ShriveAbstract:INTRODUCTION Osteoarthritis (OA) is a degenerative Joint disease involving the breakdown of articular cartilage, which is common after injury or with aging 1 . Following knee injury, sheep develop OA at a slightly accelerated rate compared to humans but with some similar patterns 2 . In an ovine knee injury model 3,4 , altered gait mechanics and degradation of the cartilage has been observed 20 weeks post anterior cruciate ligament (ACL) transection (Tx) surgery; however, potential alterations in gait at 40 weeks post ACL Tx surgery remain to be determined. Therefore, the objective of this study was to investigate the in vivo kinematics of the ovine Stifle Joint over time (20 weeks and 40 weeks) following ACL Tx. METHODS Force Plate Testing. Three skeletally mature 3 to 4-year-old female Suffolk-cross sheep (average weight 77.1kg) were led across an embedded force platform (Kistler Instrumente, Winterthur, Switzerland) until 20 hind limb hoof strikes were recorded at 1200 Hz. Peak hind limb vertical ground reaction force was determined prior to surgical plate implantation, and then serially prior to each kinematic data collection. Surgical Procedure. All sheep had a bone plate implanted onto each of the proximomedial aspect of the tibia and the distolateral aspect of the femur of their right hind limb, four weeks prior to kinematic testing. Kinematic Collection and Bone Digitization. On the day of kinematic testing, a stainless steel post was attached to each plate and an instrumented spatial linkage (ISL) mounted between them. The ISL consisted of six rotational encoders providing a measurement of position and orientation in six degrees of freedom (6-DOF) to its motion throughout gait. The in vivo kinematics of the Stifle Joint were measured while the sheep walked on a treadmill at 2 mph (0.89 m/s). Each sheep then underwent arthroscopic ACL Tx surgery on their right hind limb. The in vivo gait kinematics were measured again over time at 20 and 40 weeks post ACL Tx. Following kinematic testing at 40 weeks, the animals were euthanized. A coordinate measuring machine was used to measure anatomic landmarks on the bone with respect to the ISL in order to create an anatomically relevant coordinate system. Analysis. Data are presented as mean ± SD. RESULTS Figure 1 : The 6-DOF in vivo gait kinematics of the ovine Stifle Joint, intact (black), 22 weeks post ACL Tx (red), and 40 weeks post ACL Tx (blue). DISCUSSION AND CONCLUSIONS These data indicate that the in vivo kinematics of the ovine Stifle Joint do change over time following ACL Tx. The kinematic changes appear to be more drastic after 22 weeks, and do not entirely return back to pre-injury mechanics in all rotations and translations after 40 weeks. As shown in Figure 1, the medial-lateral as well as posterior-anterior translation of the Joint is progressively altered post ACL Tx over time. Rotationally, the internal-external kinematic curve at 22 weeks is dissimilar to the intact motion, however by 40 weeks a recovery towards the intact measurement is seen as the animal compensates for the injury. In the future, principal component analysis will be utilized to compare these gait changes. In conclusion, the transection of the ACL causes long-term changes in the in vivo kinematics of the Joint. Alterations of the kinematics may result in degradation of cartilage due to abnormal loading of the Joint and overall damage in the Joint due to compensation of the instability post ACL Tx, which is a painful and destructive condition.
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Dynamic in vivo kinematics of the intact ovine Stifle Joint.
Journal of orthopaedic research : official publication of the Orthopaedic Research Society, 2006Co-Authors: Janet E. Tapper, Janet L. Ronsky, Nigel G. Shrive, Shige Fukushima, Hiro Azuma, Gail M. Thornton, Cyril B. FrankAbstract:The ovine Stifle Joint is a promising model for the investigation of Joint mechanobiology in both normal and pathological states. The objectives of this study were to characterize three-dimensional (3D) Joint motion in the intact ovine Stifle Joint during walking, incline walking, and trotting; to determine the range of variability in normal Joint motion (intrasubject and intersubject); and to characterize the 3D ground reaction forces in the ovine hind limb during walking. 3D in vivo kinematics were measured in the right hind limb of eight sheep during walking, incline walking, and trotting on a treadmill (accuracy: 0.4 +/- 0.4 mm, 0.4 +/- 0.4 degrees). 3D ground reaction forces were measured in the hind limbs of the same subjects during walking. Joint flexion ranged from 43.1 to 77.0 degrees, and was coupled with abduction (0.0-4.1 degrees ), internal rotation (5.9-17.6 degrees), and translations in the medial (5.1-7.3 mm), anterior (21.9-23.8 mm), and superior (6.0-11.4 mm) directions. Kinematics were similar during walking, incline walking, and trotting. Intrasubject variability was small, ranging from 0.4-2.0 degrees for rotations, and 0.4-0.5 mm for translations. The active range of Joint motion was offset between subjects leading to intersubject variability of 4.1-7.4 degrees for rotations and 2.5-4.2 mm for translations. Peak vertical ground reaction forces in the hind limbs ranged from 34.5(+/-1.6) to 50.0(+/-5.6)% body weight. This study establishes the bounds of normal motion in the intact ovine Stifle Joint and provides baseline data for further studies of Joint mechanobiology in this model.
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In Vivo Measurement of the Dynamic 3-D Kinematics of the Ovine Stifle Joint
Journal of biomechanical engineering, 2004Co-Authors: Janet E. Tapper, Janet L. Ronsky, Candidate Marilyn J. Powers, Animal Care Technician Craig Sutherland, Nigel G. ShriveAbstract:The ovine Stifle Joint is a promising animal model for investigation of Joint mechanobiology. A method for in vivo measurement of dynamic 3-D kinematics of the ovine Stifle Joint is described (accuracy: 0.36 +/- 0.39 mm). Inter-subject variability in kinematics is greater than both intra-subject and inter-session variability. For future studies in which Joint kinematics are measured prior to and following controlled orthopaedic interventions, pooling of data should be avoided and each subject should act as its own control.
Christopher R. Bellenger - One of the best experts on this subject based on the ideXlab platform.
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The Effect of Total Meniscectomy versus Caudal Pole Hemimeniscectomy on the Stifle Joint of the Sheep
VCOT Archive, 1999Co-Authors: D. S. Simpson, Christopher R. Bellenger, Peter Ghosh, Y. Numata, Christopher B. LittleAbstract:The effect of total medial meniscectomy versus caudal pole hemimeniscectomy on the Stifle Joint of sheep was studied experimentally. Six months after the operations gross pathology, histopathology, cartilage biochemical analysis and the rate of proteoglycan synthesis in tissue culture were used to compare the articular cartilage harvested from the meniscectomised Joints. Degeneration of the articular cartilage from the medial compartment of the Joints was present in both of the groups. Caudal pole hemimeniscectomy induces a comparable degree of articular cartilage degeneration to total medial meniscectomy in the sheep Stifle Joint.
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The Effect of Total Meniscectomy versus Caudal Pole Hemimeniscectomy on the Stifle Joint of the Sheep
Veterinary and Comparative Orthopaedics and Traumatology, 1999Co-Authors: Christopher R. Bellenger, Peter Ghosh, Y. Numata, C. Little, D. S. SimpsonAbstract:SummaryTotal medial meniscectomy and caudal pole hemimeniscectomy were performed on the Stifle Joints of twelve sheep. The two forms of meniscectomy produced a comparable degree of postoperative lameness that resolved within two weeks of the operations. After six months the sheep were euthanatised and the Stifle Joints examined. Fibrous tissue that replaced the excised meniscus in the total meniscectomy group did not cover as much of the medial tibial condyle as the residual cranial pole and caudal fibrous tissue observed following hemimeniscectomy. The articular cartilage from different regions within the Joints was examined for gross and histological evidence of degeneration. Analyses of the articular cartilage for water content, glycosaminoglycan composition and DNA content were performed. The proteoglycan synthesis and release from explanted articular cartilage samples in tissue culture were also measured. There were significant pathological changes in the medial compartment of all meniscectomised Joints. The degree of articular cartilage degeneration that was observed following total meniscectomy and caudal pole meniscectomy was similar. Caudal pole hemimeniscectomy, involving transection of the meniscus, causes the same degree of degeneration of the Stifle Joint that occurs following total meniscectomy.The effect of total medial meniscectomy versus caudal pole hemimeniscectomy on the Stifle Joint of sheep was studied experimentally. Six months after the operations gross pathology, histopathology, cartilage biochemical analysis and the rate of proteoglycan synthesis in tissue culture were used to compare the articular cartilage harvested from the meniscectomised Joints. Degeneration of the articular cartilage from the medial compartment of the Joints was present in both of the groups. Caudal pole hemimeniscectomy induces a comparable degree of articular cartilage degeneration to total medial meniscectomy in the sheep Stifle Joint.
Alberto Arencibia - One of the best experts on this subject based on the ideXlab platform.
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RESEARCH ARTICLE Open Access Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
2016Co-Authors: Alberto Arencibia, Mario Encinoso, Daniel Morales, José Raduan Jaber, Diego Blanco, Ro Artiles, José M. VázquezAbstract:Background: The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger (Panthera tigris) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images. Results: MR images showed the bone, articular cartilage, menisci and ligaments of the normal tiger Stifle. SE T1-weighted sequence provided excellent resolution of the subchondral bones of the femur, tibia and patella compared with the GE STIR T2-weighted MR images. Articular cartilage and synovial fluid were visualised with high signal intensity in GE STIR T2-weighted sequence, compared with SE T1-weighted sequence where they appeared with intermediate intensity signal. Menisci and ligaments of the Stifle Joint were visible with low signal intensity in both sequences. The infrapatellar fat pad was hyperintense on SE T1-weighted images and showed low signal intensity on GE STIR T2-weighted images. Conclusions: MRI provided adequate information of the bony and soft tissues structures of Bengal tiger Stifle Joints. This information can be used as initial anatomic reference for interpretation of MR Stifle images and to assist in the diagnosis of diseases of this region
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Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
BMC Veterinary Research, 2015Co-Authors: Alberto Arencibia, Mario Encinoso, Alejandro Artiles, Daniel Morales, José Raduan Jaber, Diego Blanco, José M. VázquezAbstract:Background The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger (Panthera tigris) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images.
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Magnetic resonance imaging study in a normal Bengal tiger (Panthera tigris) Stifle Joint
BMC Veterinary Research, 2015Co-Authors: Alberto Arencibia, Mario Encinoso, Alejandro Artiles, Daniel Morales, José Raduan Jaber, Diego Blanco, José M. VázquezAbstract:Background The purpose of this study was to describe the normal appearance of the bony and soft tissue structures of the Stifle Joint of a Bengal tiger ( Panthera tigris ) by low-field magnetic resonance imaging (MRI), and the use of gross anatomical dissections performed as anatomical reference. A cadaver of a mature female was imaged by MRI using specific sequences as the Spin-echo (SE) T1-weighting and Gradient-echo (GE) STIR T2-weighting sequences in sagittal, dorsal and transverse planes, with a magnet of 0.2 Tesla. The bony and articular structures were identified and labelled on anatomical dissections, as well as on the magnetic resonance (MR) images. Results MR images showed the bone, articular cartilage, menisci and ligaments of the normal tiger Stifle. SE T1-weighted sequence provided excellent resolution of the subchondral bones of the femur, tibia and patella compared with the GE STIR T2-weighted MR images. Articular cartilage and synovial fluid were visualised with high signal intensity in GE STIR T2-weighted sequence, compared with SE T1-weighted sequence where they appeared with intermediate intensity signal. Menisci and ligaments of the Stifle Joint were visible with low signal intensity in both sequences. The infrapatellar fat pad was hyperintense on SE T1-weighted images and showed low signal intensity on GE STIR T2-weighted images. Conclusions MRI provided adequate information of the bony and soft tissues structures of Bengal tiger Stifle Joints. This information can be used as initial anatomic reference for interpretation of MR Stifle images and to assist in the diagnosis of diseases of this region.