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Magdalena Müller-gerbl - One of the best experts on this subject based on the ideXlab platform.
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The adaption of the bony microstructure of the human Glenoid Cavity as a result of long-term biomechanical loading
Surgical and radiologic anatomy : SRA, 2019Co-Authors: Sebastian Hoechel, Tibor Andrea Zwimpfer, Mireille Toranelli, Magdalena Müller-gerblAbstract:Structural arrangements of the bony microstructure of a joint through adaptational processes are thought to be determined by the biomechanical demands and its changes. Pursuing this theory of "form follows the biomechanical function", the load distribution of the Glenoid Cavity, as it is mirrored in its mineralization pattern, should link not only to its thickness distribution, but also will have an impact onto the trabecular network below. To prove and confirm this hypothesis, we analysed the mineral distribution in correlation to the subchondral bone plates thickness and the distribution of architectural parameters of the trabecular network below. Our findings clearly state an inhomogeneous but regular and reproducible mineral distribution pattern in respect to the biomechanical demands and a thickness of the subchondral bone plate which shows a significant correlation (78-93%). As for the trabecular network below, the distribution of the analysed parameters also revealed an inhomogeneous distribution with a regular pattern in correlation to the biomechanical impact. We found distinctive maxima of material distribution and stability (bone volume 79%, plate-like architecture 77%) situated below areas of high long-term load intake. With increasing depth, the trabecular network administers the expression of each structural parameter following the fact that the strain energy gets more and more evenly distributed and changes from a high degree of differentiation just beneath the SBP to a more equal distribution within the deeper areas. After all, the biomechanical situation of a joint directly influences the bony formation of the subchondral bone plate and the trabecular network below.
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Mineralisation and mechanical strength of the Glenoid Cavity subchondral bone plate.
International Orthopaedics, 2011Co-Authors: Marko Kraljević, Valentin Zumstein, Rolf Hügli, Dieter Wirz, Magdalena Müller-gerblAbstract:Purpose Failures in total shoulder replacements are often due to aseptic loosening of the Glenoid component; the subchondral bone plate is an important factor governing primary fixation of implant materials. Therefore, we investigated characteristic mineralisation patterns of the subchondral bone plate, which demonstrate long-term stress on articular surfaces, age-related changes, postsurgical biomechanical situations and regions of fixation. Using computed tomography osteo-absorptiometry (CT-OAM), these distribution patterns can be demonstrated in vivo. The aim of this study was to investigate the relationship between subchondral bone-plate mineralisation measured with CT-OAM and the mechanical strength measured by indentation.
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The mineralization patterns at the subchondral bone plate of the Glenoid Cavity in healthy shoulders.
Journal of shoulder and elbow surgery, 2002Co-Authors: Christoph Schulz, Magdalena Müller-gerbl, H. Anetzberger, M. Pfahler, Christoph R. Becker, Hans J. RefiorAbstract:The distribution of mineralization of the subchondral bone plate (DMSB) is used as a parameter for the individual stress distribution of joints. In this study the DMSB of the Glenoid from healthy glenohumeral joints was analyzed. In a standardized manner, 44 macroscopically normal shoulder specimens (28 individuals aged 18 to 96 years) were selected and DMSB of the Glenoid was evaluated by computed tomography osteoabsorptiometry. The mineralization patterns were described, and the 2 most frequent maxima of density were localized and statistically assessed to analyze any influence of age, side, or shape of the Glenoid on DMSB. An anterior-superior maximum was found in 100% and a posterior maximum in 82%. Three different patterns of DMSB were distinguished in relation to the constant anterior-superior maximum: 68% were not combined with a further central or anterior-inferior maximum (type A), whereas a central maximum coexisted in 18% (type B) and an anterior-inferior maximum in 14% (type C). The localization of the anterior-superior and posterior maxima was independent of age or side of the Glenoid, indicating a constant long-term stress distribution in healthy glenohumeral joints. The typical localization of the density maxima showed that stress distribution is usually peripherical (82%) and often bicentric. Functional aspects related to internal rotation of the arm support a more constant anterior than posterior stress on the Glenoid surface.
T Klumpen - One of the best experts on this subject based on the ideXlab platform.
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the Glenoid notch and its relation to the shape of the Glenoid Cavity of the scapula
Journal of Anatomy, 1997Co-Authors: Andreas Prescher, T KlumpenAbstract:The prevalence of a notch in the anterior margin of the Glenoid Cavity of 236 scapulae (118 female, 118 male) was investigated. The notch was found in 129 scapulae (55%) and gave rise to a pear-shaped Cavity. In 107 scapulae (45%) the notch was absent, the shape of the Cavity being oval. No sex difference was found in the prevalence of the notch. If a distinct notch exists, the Glenoid labrum is not attached to bone at the notch and is therefore liable to be sheared off (Bankart lesion).
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does the area of the Glenoid Cavity of the scapula show sexual dimorphism
Journal of Anatomy, 1995Co-Authors: Andreas Prescher, T KlumpenAbstract:Abstract The area of the Glenoid Cavity was determined in 214 scapulae (114 male, 100 female). Mean values of 9.87 cm2 for the males and 7.18 cm2 for the females were found. Presentation of the values as a histogram showed a bimodal distribution indicating sexual dimorphism, which was confirmed by the Mann-Whitney-Wilcoxon test for unconnected samples. The area of the Cavity can therefore be used for the sexing of a skeleton. With the described method 60% of males but only 36% of females can be graded unambiguously.
Andreas Prescher - One of the best experts on this subject based on the ideXlab platform.
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the Glenoid notch and its relation to the shape of the Glenoid Cavity of the scapula
Journal of Anatomy, 1997Co-Authors: Andreas Prescher, T KlumpenAbstract:The prevalence of a notch in the anterior margin of the Glenoid Cavity of 236 scapulae (118 female, 118 male) was investigated. The notch was found in 129 scapulae (55%) and gave rise to a pear-shaped Cavity. In 107 scapulae (45%) the notch was absent, the shape of the Cavity being oval. No sex difference was found in the prevalence of the notch. If a distinct notch exists, the Glenoid labrum is not attached to bone at the notch and is therefore liable to be sheared off (Bankart lesion).
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does the area of the Glenoid Cavity of the scapula show sexual dimorphism
Journal of Anatomy, 1995Co-Authors: Andreas Prescher, T KlumpenAbstract:Abstract The area of the Glenoid Cavity was determined in 214 scapulae (114 male, 100 female). Mean values of 9.87 cm2 for the males and 7.18 cm2 for the females were found. Presentation of the values as a histogram showed a bimodal distribution indicating sexual dimorphism, which was confirmed by the Mann-Whitney-Wilcoxon test for unconnected samples. The area of the Cavity can therefore be used for the sexing of a skeleton. With the described method 60% of males but only 36% of females can be graded unambiguously.
Philippe Büchler - One of the best experts on this subject based on the ideXlab platform.
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a statistical shape model to predict the premorbid Glenoid Cavity
Journal of Shoulder and Elbow Surgery, 2018Co-Authors: Daniel Abler, Steve Berger, Alain Farron, Fabio Becce, Alexandre Terrier, Philippe BüchlerAbstract:BACKGROUND This study proposes a method for inferring the premorbid Glenoid shape and orientation of scapulae affected by glenohumeral osteoarthritis (OA) to inform restorative surgery. METHODS A statistical shape model (SSM) built from 64 healthy scapulae was used to reconstruct the premorbid Glenoid shape based on anatomic features that are considered unaffected by OA. First, the method was validated on healthy scapulae by quantifying the accuracy of the predicted shape in terms of surface distance, Glenoid version, and inclination. The SSM-based reconstruction was then applied to 30 OA scapulae. Glenoid version and inclination were measured fully automatically and compared between the original OA Glenoids, SSM-based Glenoid reconstructions, and healthy scapulae. RESULTS Validation on healthy scapulae showed a root-mean-square surface distance between original and predicted Glenoids of 1.0 ± 0.2 mm. The prediction error was 2.3° ± 1.8° for Glenoid version and 2.1° ± 2.0° for inclination. When applied to an OA dataset, SSM-based reconstruction restored average Glenoid version and inclination to values similar to the healthy situation. No differences were observed between average orientation values measured on SSM-based reconstructed and healthy scapulae (P ≥ .10). However, the average orientation of the reconstructed premorbid Glenoid differed from the average orientation of OA Glenoids for Walch classes A1 (version) and B2 (version, inclination, and medialization). CONCLUSION The proposed SSM can predict the premorbid Glenoid Cavity of healthy scapulae with millimeter accuracy. This technique has the potential to reconstruct the premorbid Glenoid Cavity shape, as it was prior to OA, and thus to guide the positioning of Glenoid implants in total shoulder arthroplasty.
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Is The Glenoid Orientation And Curvature Radius Symmetric On The Left and Right Scapula
2017Co-Authors: Elham Taghizadeh, Steve Berger, Alain Farron, Fabio Becce, Alexandre Terrier, Philippe BüchlerAbstract:Background During placement of Glenoid prosthesis, the surgeon aims at restoring the orientation of the natural Glenoid. However, in case of degenerative disease or trauma, the original shape of the bone is unknown. In this case, the information of the contralateral scapula could be used to plan the intervention. However little is known on the symmetry/asymmetry of the scapula. Objectives The objective of this study was to measure and compare the version and curvature radius of the Glenoid Cavity, for the left and right side of healthy young subjects.
Marko Kraljević - One of the best experts on this subject based on the ideXlab platform.
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Mineralisation and mechanical strength of the Glenoid Cavity subchondral bone plate.
International Orthopaedics, 2011Co-Authors: Marko Kraljević, Valentin Zumstein, Rolf Hügli, Dieter Wirz, Magdalena Müller-gerblAbstract:Purpose Failures in total shoulder replacements are often due to aseptic loosening of the Glenoid component; the subchondral bone plate is an important factor governing primary fixation of implant materials. Therefore, we investigated characteristic mineralisation patterns of the subchondral bone plate, which demonstrate long-term stress on articular surfaces, age-related changes, postsurgical biomechanical situations and regions of fixation. Using computed tomography osteo-absorptiometry (CT-OAM), these distribution patterns can be demonstrated in vivo. The aim of this study was to investigate the relationship between subchondral bone-plate mineralisation measured with CT-OAM and the mechanical strength measured by indentation.