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Heike Walles - One of the best experts on this subject based on the ideXlab platform.
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Three-Dimensional Coculture of Meniscal Cells and Mesenchymal Stem Cells in Collagen Type I Hydrogel on a Small Intestinal Matrix-A Pilot Study Toward Equine Meniscus Tissue Engineering.
Tissue engineering. Part A, 2017Co-Authors: Antje Kremer, Iris Ribitsch, Jenny Reboredo, Julia Dürr, Monika Egerbacher, Florien Jenner, Heike WallesAbstract:Meniscal injuries are the most frequently encountered soft tissue injuries in the Equine Stifle joint. Due to the inherent limited repair potential of meniscal tissue, meniscal injuries do not only affect the meniscus itself but also lead to impaired joint homeostasis and secondary osteoarthritis. The presented study compares 3D coculture constructs of primary Equine mesenchymal stem cells (MSC) and meniscus cells (MC) seeded on three different scaffolds—a cell-laden collagen type I hydrogel (Col I gel), a tissue-derived small intestinal matrix scaffold (SIS-muc) and a combination thereof—for their qualification to be applied for meniscus tissue engineering. To investigate cell attachment of primary MC and MSC on SIS-muc matrix SEM pictures were performed. For molecular analysis, lyophilized samples of coculture constructs with different cell ratios (100% MC, 100% MSC, and 50% MC and 50% MSC, 20% MC, and 80% MSC) were digested and analyzed for DNA and GAG content. Active matrix remodeling of 3D coculture ...
Steven P. Arnoczky - One of the best experts on this subject based on the ideXlab platform.
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Experimental and Basic Research Studies Three dimensional, radiosteriometric analysis (RSA) of Equine Stifle kinematics and articular surface contact: A cadaveric study
2016Co-Authors: S E Halley, M J Bey, J A Haladik, Michael Lavagnino, Steven P. ArnoczkyAbstract:Reasons for performing study: Studies examining the effect of Stifle joint angle on tibial rotation, adduction–abduction angle and articular contact area are lacking. Objectives: To test the hypothesis that tibial rotation, adduction–abduction angle and articular contact area change with Stifle joint angle. Study design: Descriptive study of normal kinematics and articular contact patterns of the Equine Stifle through the functional range of motion using 3 dimensional (3D) radiosteriometric analysis (RSA) and Equine cadaver Stifles. Methods:Multiple, radiopaque markers were embedded in the distal femur and proximal tibia and sequential, biplanar x-rays captured as the Stifle was passively extended from 110 ° to full extension. Computer-programmed RSAwas used to determine changes in abduction–adduction and internal–external rotation angles of the tibia during Stifle extension as well as articular contact patterns (total area and areas of high contact) through the range of motion. Results: The tibia rotated externally (P<0.001) as the Stifle was extended. Tibial abduction occurred from 110–135 ° of extension (P<0.001) and tibial adduction occurred from 135 ° through full extension (P = 0.009). The centre of joint contact moved cranially on both tibial condyles during extension with the lateral moving a greater distance than the medial (P = 0.003). Articular contact area decreased (P = 0.001) in the medial compartment but not in the lateral compartment (P = 0.285) as the Stifle was extended. The area of highest joint contact increased on the lateral tibial condyle (P<0.001) with extension but decreased (P = 0.001) on the medial tibial condyle. Conclusions: Significant changes occur in tibial rotation, adduction–abduction angle and articular contact area of the Equine Stifle through the functional range of motion. Understanding the normal kinematics of the Equine Stifle and the relationship between joint positions and articular contact areas ma
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three dimensional radiosteriometric analysis rsa of Equine Stifle kinematics and articular surface contact a cadaveric study
Equine Veterinary Journal, 2014Co-Authors: S E Halley, M J Bey, J A Haladik, Michael Lavagnino, Steven P. ArnoczkyAbstract:Summary Reasons for performing study Studies examining the effect of Stifle joint angle on tibial rotation, adduction–abduction angle and articular contact area are lacking. Objectives To test the hypothesis that tibial rotation, adduction–abduction angle and articular contact area change with Stifle joint angle. Study design Descriptive study of normal kinematics and articular contact patterns of the Equine Stifle through the functional range of motion using 3 dimensional (3D) radiosteriometric analysis (RSA) and Equine cadaver Stifles. Methods Multiple, radiopaque markers were embedded in the distal femur and proximal tibia and sequential, biplanar x-rays captured as the Stifle was passively extended from 110° to full extension. Computer-programmed RSA was used to determine changes in abduction–adduction and internal–external rotation angles of the tibia during Stifle extension as well as articular contact patterns (total area and areas of high contact) through the range of motion. Results The tibia rotated externally (P<0.001) as the Stifle was extended. Tibial abduction occurred from 110–135° of extension (P<0.001) and tibial adduction occurred from 135° through full extension (P = 0.009). The centre of joint contact moved cranially on both tibial condyles during extension with the lateral moving a greater distance than the medial (P = 0.003). Articular contact area decreased (P = 0.001) in the medial compartment but not in the lateral compartment (P = 0.285) as the Stifle was extended. The area of highest joint contact increased on the lateral tibial condyle (P<0.001) with extension but decreased (P = 0.001) on the medial tibial condyle. Conclusions Significant changes occur in tibial rotation, adduction–abduction angle and articular contact area of the Equine Stifle through the functional range of motion. Understanding the normal kinematics of the Equine Stifle and the relationship between joint positions and articular contact areas may provide important insight into the aetiology and location of common Stifle joint pathologies (articular cartilage and meniscal lesions).
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Three dimensional, radiosteriometric analysis (RSA) of Equine Stifle kinematics and articular surface contact: A cadaveric study
Equine veterinary journal, 2013Co-Authors: S E Halley, M J Bey, J A Haladik, Michael Lavagnino, Steven P. ArnoczkyAbstract:Summary Reasons for performing study Studies examining the effect of Stifle joint angle on tibial rotation, adduction–abduction angle and articular contact area are lacking. Objectives To test the hypothesis that tibial rotation, adduction–abduction angle and articular contact area change with Stifle joint angle. Study design Descriptive study of normal kinematics and articular contact patterns of the Equine Stifle through the functional range of motion using 3 dimensional (3D) radiosteriometric analysis (RSA) and Equine cadaver Stifles. Methods Multiple, radiopaque markers were embedded in the distal femur and proximal tibia and sequential, biplanar x-rays captured as the Stifle was passively extended from 110° to full extension. Computer-programmed RSA was used to determine changes in abduction–adduction and internal–external rotation angles of the tibia during Stifle extension as well as articular contact patterns (total area and areas of high contact) through the range of motion. Results The tibia rotated externally (P
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Meniscal translocation and deformation throughout the range of motion of the Equine Stifle joint: an in vitro cadaveric study.
Equine veterinary journal, 2010Co-Authors: J. G. Fowlie, John A. Stick, Steven P. Arnoczky, Anthony PeaseAbstract:Reason for performing study By study of the translocation and deformation of Equine menisci throughout the range of motion, it may be possible to identify potential mechanical factors in the pathogenesis of injury to the cranial horn of the medial meniscus. Objective To quantitatively document meniscal translocation and deformation using radiographic and MR imaging, and to evaluate for potential variation between the medial and lateral menisci. Methods Radiographic markers were embedded in the periphery of the menisci in 6 cadaver Stifles. Proximal-distal radiographs were taken at 15° intervals ranging from full flexion (30°) to full extension (160°). Magnetic resonance imaging sequences of 3 additional cadaver Stifles were obtained in axial and sagittal planes at the predetermined Stifle angles. Results A significantly greater overall mean cranial-caudal translocation (1.6 times) of the lateral meniscus relative to the medial was seen from full extension to full flexion (P = 0.002). The cranial horn of the medial meniscus was the least mobile of the 4 horns, yet a significant cranial displacement relative to the cranial horn of the lateral meniscus was seen in the terminal 10° of extension. MRI images revealed a significantly greater axial compressive strain in the cranial horn of the medial meniscus relative to the cranial horn of the lateral meniscus in the terminal 10° of extension (P = 0.017). Conclusion The Equine menisci exhibit a cranial-caudal translocation over the tibia throughout the range of motion. While the cranial horn of the medial meniscus is the least mobile of the 4 horns, it undergoes significant cranial translocation and axial compression in the terminal 10° of extension. Potential relevance Hyperextension of the Stifle may place the cranial horn of the medial meniscus at risk of injury and thus explain the higher prevalence of meniscal tears at this location.
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Consideration of anatomic and radiographic features of the caudal pouches of the femorotibial joints of horses for the purpose of arthroscopy.
American Journal of Veterinary Research, 1994Co-Authors: Troy N. Trumble, John A. Stick, Steven P. Arnoczky, Diana S. RosensteinAbstract:: Development of an arthroscopic approach to the caudal pouches of the Equine Stifle has been necessary because cranial approaches do not allow access to articular lesions in the caudal aspect of the joint. Therefore, the anatomy of the caudal region was examined in 52 cadaver limbs by use of gross dissection (29), x-ray-computed tomography (6), fluoroscopy (8), or arthroscopy (9). Additionally, using arthroscopic techniques developed in Equine cadaver limbs, 3 Stifles from 2 anesthetized horses were arthroscopically explored. Fluoroscopy was used to verify needle placement for joint injection and filling patterns of each femorotibial joint. The medial femorotibial joint sac (n = 4) held a mean +/- SD 41.67 +/- 5.77 ml of injection fluid, and the lateral femorotibial joint sac (n = 4) held a mean 61.67 +/- 2.89 ml of injection fluid. Vital structures that inadvertently could be damaged during arthroscopy of the caudal pouches of the Stifle included the peroneal nerve (located approx 7 cm caudal to the lateral collateral ligament), the popliteal artery and vein (situated directly between the medial and lateral femoral condyles), and the lateral femoral condyle (most often traumatized during arthroscopy). The tendon of the popliteus muscle, which is contiguous with the joint capsule of the caudal pouch of the lateral femorotibial joint, made arthroscopic exploration of this pouch particularly difficult.
M. Lowerison - One of the best experts on this subject based on the ideXlab platform.
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Mapping of donor and recipient site properties for osteochondral graft reconstruction of subchondral cystic lesions in the Equine Stifle joint.
Equine veterinary journal, 2010Co-Authors: Adele Changoor, Mark B. Hurtig, R. J. Runciman, A. J. Quesnel, James P. Dickey, M. LowerisonAbstract:Summary Reasons for performing study: To improve osteochondral graft reconstruction of subchondral cystic lesions in the medial and lateral femoral condyles by matching the material properties of donor and recipient sites. Objectives: To measure biomechanical and biochemical parameters that influence the function and healing of osteochondral grafts used to reconstruct subchondral cystic lesions. Hypothesis: Suitable donor sites are available within the Stifle joint for reconstructing the femoral condyles, despite considerable regional property variation. Methods: Fifty-six osteochondral cores were harvested from 6 distal femurs for initial studies that determined subchondral bone modulus of elasticity and ultimate stress. In a second study, 28 osteochondral cores were harvested from 6 distal femurs to measure cartilage aggregate modulus, thickness and sulphated glycosaminoglycan (sGAG) content. Using micro-CT imaging, subchondral bone mineral density and bone volume fraction were also measured. In both studies 2-dimensional contour plots using a bicubic interpolation method and normalised data were generated to allow visual comparison of joint surface characteristics. Statistical comparisons between donor and recipient site raw data were made using an ANOVA for repeated measures with a post hoc Tukey test. Results: Material properties of cartilage and bone vary considerably over the surface of the Stifle joint but the central region of the medial condyle, where subchondral cystic lesions frequently occur, typically demonstrated bone strength and modulus values of the highest observed. Cartilage thickness and aggregate modulus were highest in the medial femoral condyle and axial aspect of the lateral condyle. Conclusions: Material properties of the grafts from the trochlear groove and axial aspect of the lateral trochlear ridge were the closest match for those found in the medial condyle, whereas properties of the lateral condyle were most similar to those found in the trochlear groove and axial aspect of the medial trochlear ridge.
Jimmy Saunders - One of the best experts on this subject based on the ideXlab platform.
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Ultrasonographic Findings in the Stifle Joint of Active Jumping and Dressage Horses
Rheumatology: Current Research, 2016Co-Authors: Elke Van Der Vekens, Erik H. J. Bergman, Arie C Hoogendoorn, Els Raes, Bernadette Van Ryssen, Katrien, Erperren, Jimmy SaundersAbstract:Objective Ultrasonography (US) is frequently used to evaluate the Equine Stifle joint. Some soft tissue US findings are known to be clinically relevant, while others are considered incidental. These considerations are not always evidence-based. This study aims to describe the US findings observed in the Stifle of clinically sound, active jumping and dressage horses. Design: Prospective study Animals: 46 Warmblood horses Procedures: To be included in this study, the horses had to fulfil 4 criteria: (1) in competition at least 1 time/month at national or international level, (2) in full work, (3) free of lameness, (4) no complains of the horse’s performances. Both Stifle joints of each horse were scanned systematically by US and US findings were recorded. Results: 46 Warmblood horses fulfilled the criteria. US was normal in 21 horses, whereas abnormalities were detected in one or both Stifles in 7 and 18 horses, respectively. Changes were seen in all compartments of the Stifle joints: medial femorotibial joint (18 horses): osteophytes, effusion, subchondral cyst in the medial femoral condyle and lesions in the cranial meniscotibial ligament or medial collateral ligament; lateral femorotibial joint (4 horses): mild effusion, subchondral cyst in lateral femoral condyle; femoropatellar joint (16 horses): effusion, lesions in medial or intermediate patellar ligament or osteochondrotic lesions. Conclusion and Clinical relevance: Mild changes can be found ultrasonographically in the Stifles of sport horses. Periarticular new bone formation was observed in 25% of the horses, apparently clinically not relevant. Lesions in the menisci, the tendinous portions of the popliteus muscle, long digital extensor muscle or peroneus tertius muscle or the lateral collateral ligament were not observed.
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Computed tomographic anatomy of the Equine Stifle joint.
American journal of veterinary research, 2011Co-Authors: Elke Van Der Vekens, Erik H. J. Bergman, Els Raes, Katrien Vanderperren, Sarah M. Puchalski, Henri Van Bree, Jimmy SaundersAbstract:Objective—To provide a detailed computed tomography (CT) reference of the anatomically normal Equine Stifle joint. Sample—16 hind limbs from 8 Equine cadavers; no horses had evidence of orthopedic disease of the Stifle joints. Procedures—CT of the Stifle joint was performed on 8 hind limbs. In all limbs, CT was also performed after intra-articular injection of 60 mL of contrast material (150 mg of iodine/mL) in the lateral and medial compartments of the femorotibial joint and 80 mL of contrast material in the femoropatellar joint (CT arthrography). Reformatted CT images in the transverse, parasagittal, and dorsal plane were matched with corresponding anatomic slices of the 8 remaining limbs. Results—The femur, tibia, and patella were clearly visible. The patellar ligaments, common origin of the tendinous portions of the long digital extensor muscle and peroneus tertius muscle, collateral ligaments, tendinous portion of the popliteus muscle, and cranial and caudal cruciate ligaments could also be consisten...
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Cross-sectional anatomy and comparative ultrasonography of the Equine medial femorotibial joint and its related structures.
Equine Veterinary Journal, 2010Co-Authors: M. Hoegaerts, M. Nicaise, H. Van Bree, Jimmy SaundersAbstract:Summary Reasons for performing study: Injuries of the Equine Stifle are frequent causes of hindlimb lameness. Ultrasonography is useful for the diagnosis of many soft tissue lesions but, until recently, its application to the Equine Stifle has been limited to a description of normal and abnormal structures. A comparative study using gross anatomical sections to identify all structures visible on ultrasonographic images of the Equine Stifle has not previously been reported. Objectives: To provide a comprehensive comparative cross-sectional atlas of the normal Equine medial femorotibial (MFT) joint and its related structures using ultrasonography. Methods: The Stifle joints of 15 cadaver limbs were examined ultrasonographically using a systematic approach. Ten different scanning planes were defined. The lateral and medial femorotibial and the femoropatellar joints were injected with pigments of different colours. Each leg was frozen (10 in extension and 5 in flexion) and cut into slices corresponding to the different scanning planes. According to the different ultrasonographic reference images, 10 representative anatomical images were selected and digitised. Results: All bony and soft tissue structures were identified on the anatomical sections and subsequently located on the corresponding ultrasonographic images, except the caudal meniscotibial ligaments. Visualisation of the cruciate ligaments was a challenge due to their position and oblique orientation. Conclusions: Ultrasonography is a very useful technique for imaging both soft tissue and bony structures of the MFT joint and its related structures, although a protocol is required to perform a systematic and standardised ultrasonographic examination. Good anatomical knowledge is mandatory for identification of the different structures. Potential relevance: This study should contribute to 1) knowledge of the ultrasonographic anatomy of the Equine MFT joint and its related structures, 2) use of a protocol for a standardised ultrasonographic examination and 3) the ability to recognise abnormal structures.
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Ultrasonography of the canine and Equine Stifle joint: correlation with humans
Ultrasound, 2009Co-Authors: Jimmy Saunders, Elke Van Der VekensAbstract:The gross anatomy and physiology of the knee are similar in people, dogs and horses. However, evolution, way of life and the use of horses and dogs means that the detailed anatomy, physiology and disease processes have altered with time. In dogs, cranial cruciate ligament injury (30%), degenerative joint disease (17%) and patellar ligament injury (17%) are the most frequently encountered disease processes, while in horses, osteochondrosis and subchondral cysts (52%), medial collateral ligament injury (28%), patellar ligament injury (23%), degenerative joint disease (23%) and medial meniscus lesions (19%) are more frequently reported. In addition the technological possibilities and the cooperation of the patient are different between human and veterinary medicine. In people, ultrasonography of the knee is easy to perform and gives lots of information, but it has inferior diagnostic capabilities compared to MRI. In dogs, the small size of the joint and large variation between breeds are responsible for the ...
Antje Kremer - One of the best experts on this subject based on the ideXlab platform.
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Three-Dimensional Coculture of Meniscal Cells and Mesenchymal Stem Cells in Collagen Type I Hydrogel on a Small Intestinal Matrix-A Pilot Study Toward Equine Meniscus Tissue Engineering.
Tissue engineering. Part A, 2017Co-Authors: Antje Kremer, Iris Ribitsch, Jenny Reboredo, Julia Dürr, Monika Egerbacher, Florien Jenner, Heike WallesAbstract:Meniscal injuries are the most frequently encountered soft tissue injuries in the Equine Stifle joint. Due to the inherent limited repair potential of meniscal tissue, meniscal injuries do not only affect the meniscus itself but also lead to impaired joint homeostasis and secondary osteoarthritis. The presented study compares 3D coculture constructs of primary Equine mesenchymal stem cells (MSC) and meniscus cells (MC) seeded on three different scaffolds—a cell-laden collagen type I hydrogel (Col I gel), a tissue-derived small intestinal matrix scaffold (SIS-muc) and a combination thereof—for their qualification to be applied for meniscus tissue engineering. To investigate cell attachment of primary MC and MSC on SIS-muc matrix SEM pictures were performed. For molecular analysis, lyophilized samples of coculture constructs with different cell ratios (100% MC, 100% MSC, and 50% MC and 50% MSC, 20% MC, and 80% MSC) were digested and analyzed for DNA and GAG content. Active matrix remodeling of 3D coculture ...