Sudesh Sivarasu

Bio: Sudesh Sivarasu is an academic researcher from University of Cape Town. The author has contributed to research in topics: Knee Joint & Stress shielding. The author has an hindex of 6, co-authored 60 publications receiving 158 citations. Previous affiliations of Sudesh Sivarasu include VIT University.

Novel Approach for Designing a Low Weight Hip Implant Used in Total Hip Arthroplasty Adopting Skeletal Design Techniques

Abstract: Aseptic loosening is the major cause of failure of hip implants after total hip arthroplasty. Stress shielding of the femur is known to be the principal factor involved in the aseptic loosening of hip implants. Solid stems are found to have a greater rigidity; therefore, they transfer less load proximally, which results in greater stress shielding of the proximal femur. A stem of low stiffness alone would not suffice in achieving a reduced or optimal stress shielding. The femoral stem of the light weight hip implant has a skeletal design with a hexagonal base and neck cross-section. This novel design would ameliorate the implant fixation, aid in optimal rigidity, enhance the medullary revascularization, and offer better mobility to the patient.

Subject-specific shoulder muscle attachment region prediction using statistical shape models: A validity study

Abstract: Subject-specific musculoskeletal models can predict accurate joint and muscle biomechanics thereby helping clinicians and surgeons. Current modeling strategies do not incorporate accurate subject-specific muscle parameters. This study reports a statistical shape model (SSM) based method to predict subject-specific muscle attachment regions on shoulder bones and illustrates the concurrent validity of the predictions. Augmented SSMs of scapula and humerus bones were built using bone meshes and five muscle attachment (origin/insertion) regions which play important role in the shoulder motion and function. Muscle attachments included Subscapularis, Supraspinatus, Infraspinatus, Teres Major and Teres Minor on both the bones. The regions were represented by subset of vertices on the bone meshes and were tracked using vertex identifiers. Subject-specific muscle attachment regions were predicted using external set of bones not used in building the SSMs. Validity of predictions was determined by visual inspection and also by using four similarity measures between predicted and manually segmented regions. Excellent concurrent validity was found indicating the higher accuracy of predictions. This method can be effectively employed in modeling pipelines or in automatic segmentation of medical images. Further validations are warranted on all the muscles of the shoulder complex.

Mechanical performance of Ilizarov circular external fixators in comparison with other external fixators : Newest knowledge of external skeletal fixation devices

Abstract: The fundamental difference of the Ilizarov fixator is the type of pins used for bone fixation, i.e., Kirschner wires 1.5 mm and 1.8 mm in diameter, pretensioned from 50 to 130 kg before being affixed to the rings that are connected and fixed by threaded rods. The mechanical characteristics of external fixators may influence the biologic environment at the fracture site and ultimately decide the outcome of a surgical procedure. Thus, knowledge of the mechanical properties of the Ilizarov fixator is essential to a surgeon using it in clinical practice. The main objective of this study was to quantitate the mechanical behavior of the standard Ilizarov fixator under different loading conditions and fixator frame/wire configurations

Proximal Humerus Fractures: Evaluation and Management in the Elderly Patient:

Abstract: Introduction:Proximal humerus fractures are common in the elderly. The evaluation and management of these injuries is often controversial. The purpose of this study is to review recent evidence and...

Mastering CAD/CAM

Abstract: Part I: Using CAD/CAM Systems 1 Introduction 2 3D Modeling and Viewing 3 Modeling Aids and Tools 4 Engineering Drawings 5 CAD/CAM Programming Part II: Geometric Modeling 6 Curves 7 Surfaces 8 NURBS 9 Solids 10 Features Part III: Computer Graphics 11 Graphics Display 12 Transformations 13 Visualization 14 Computer Animation Part IV: Product Design and Development 15 Mass Properties 16 Assembly Modeling 17 Finite Element Method 18 Product Data Exchange 19 Collaborative Design Part V: Product Manufacturing and Management 20 Engineering Tolerances 21 Process Planning 22 Part Programming 23 Product Lifecycle Management Appendix A Bibliography Appendix B Linear Algebra Appendix C ANSI and ISO Tolerance Tables

Privatisation in Developing Countries: What Are the Lessons of Recent Experience?

Abstract: This paper reviews recent empirical evidence on privatisation in developing countries. Particular emphasis is placed on new areas of research such as the distributional impacts of privatisation. Overall, the literature now reflects a more cautious and nuanced evaluation of privatisation. Thus it is found that private ownership alone does not automatically generate economic and employment gains in developing economies; pre-conditions (especially the regulatory infrastructure) and the process of privatisation are important to attain a positive impact. Such factors include well-designed and sequenced reforms; the implementation of complementary policies; the creation of regulatory capacity; attention to poverty and social impacts; and strong public communication; a list which is often challenging in developing countries. However, the studies do identify scope for efficiency-enhancing privatisation which also promotes equity in developing countries.