Épaule | EPFL Graph Search

L'épaule (nom féminin) est la région morphologique se situant à la jonction du tronc avec le membre supérieur. On lui distingue deux régions :

la région axillaire correspondant à l'aisselle,
la région deltoïdienne ou moignon de l'épaule correspondant au relief du muscle deltoïde.

L'épaule comporte 2 articulations qui fonctionnent de concert et qui concourent à en faire le complexe articulaire le plus mobile du corps humain. Elle permet d'orienter le membre supérieur dans l'espace, autorisant en particulier son extrémité effectrice, la main, à assurer ses rôles de préhension et de communication avec l'environnement situé à sa portée. Biomécanique et anatomie fonctionnelle de l'épaule L'épaule est un complexe d'articulations et de muscles unissant le membre supérieur au tronc. Il s'agit de l'articulation la plus mobile du corps humain. L'épaule est constituée d'os, de ligaments, de tendons et de muscles qui assurent une connexion entre le bras et le torse. Elle peut d

Comparison of Muscle Coordination in Two Patient Specific Shoulder Models

Nathalie Ballanfat

The shoulder provides mobility to the upper limb and is thus necessary for lots of activities. Consequently injuries in the shoulder joint affect the patient in his daily life. The study of shoulder pathologies is however difficult : each patient has his individual anatomy and his own lifestyle which have an impact on his shoulder biomechanical pattern. This is why patient specific shoulder models are necessary to explore precise and specific features of the patient’s shoulder joint. The goal of this project was to analyse the impact of individual anatomy on the shoulder muscle coordination. To do this, we built two patient specific musculoskeletal models. The first one was based on MRI scans of a male volunteer, the second one on MRI scans of a female volunteer. We observed both models to predict similar muscle force patterns and joint reaction forces. However, the models predicted variations in muscle force intensity, that were related to the anatomic changes.

2015

A statistical shape model to predict the premorbid glenoid cavity

Daniel Abler, Steve Michel Berger, Philippe Büchler, Alain Farron, Alexandre Terrier

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 degrees +/- 1.8 degrees for glenoid version and 2.1 degrees +/- 2.0 degrees 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 Al (version) and 132 (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 arthmplasty. (C) 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

MOSBY-ELSEVIER2018

3D modeling of the human upper limb including the biomechanics of joints, muscles and soft tissues

The challenge in virtual human modeling is to achieve the representation of the main human characteristics with as much realism as possible. Such achievements would allow the simulation and/or analysis of many virtual situations involving humans. Simulation is especially useful to derive information from the models so as to predict and/or reproduce the behaviors that would be observed in real situations. Computer methods in visualization and simulation have thus great potential for advances in medicine. The processes of strength generation and motion coordination are some of these phenomena for which there is still much remaining to be understood. The human shoulder is also probably the articulation of the human body which deserves more than any other to be named "terra incognita". Investigations towards the biomechanical modeling and simulation of the human upper limb are therefore presented in this study. It includes thorough investigation into the musculoskeletal anatomy and biomechanics of the human upper limb, into the biomechanical constitutive modeling of muscles and soft tissues, and into the nonlinear continuum mechanics and numerical methods, especially the incremental finite element methods, necessary for their simulation. On this basis, a 3-D biomechanical musculoskeletal human upper limb model has been designed using the Visible Human Data provided by the U.S. National Library of Medicine, and applied to the dynamic musculoskeletal simulation of the human upper limb. This research has been achieved in the context of the EU ESPRIT Project CHARM, whose objective has been to develop a comprehensive human animation resource database and a set of software tools allowing the modeling of the human complex musculoskeletal system and the simulation of its dynamics, including the finite element simulation of soft tissue deformation and muscular contraction. An investigation towards the application of this knowledge for the realistic modeling and animation of the upper limb in computer animation is then presented. The anatomical and biomechanical modeling of the scapulo-thoracic constraint and the shoulder joint sinus cones are proposed and applied to the realistic animation, using inverse kinematics, of a virtual skeleton and an anatomic musculoskeletal body model.

EPFL1999

3D modeling of the human upper limb including the biomechanics of joints, muscles and soft tissues

EPFL1999

A statistical shape model to predict the premorbid glenoid cavity

Daniel Abler, Steve Michel Berger, Philippe Büchler, Alain Farron, Alexandre Terrier

MOSBY-ELSEVIER2018