Jay R. Goldberg

A multicenter retrieval study of the taper interfaces of modular hip prostheses

A multicenter retrieval analysis of 231 modular hip implants was done to investigate the effects of material combination, metallurgic condition, flexural rigidity, head and neck moment arm, neck length, and implantation time on corrosion and fretting of modular taper surfaces. Scores for corrosion and fretting were assigned to medial, lateral, anterior, and posterior quadrants of the necks, and proximal and distal regions of the heads. Neck and head corrosion and fretting scores were found to be significantly higher for mixed alloy versus similar alloy couples. Moderate to severe corrosion was observed in 28% of the heads of similar alloy couples and 42% of the heads of mixed alloy couples. Differences in corrosion scores were observed between components made from the same base alloy, but of different metallurgic conditions. Corrosion and fretting scores tended to be higher for heads than necks. Implantation time and flexural rigidity of the neck were predictors of head and neck corrosion and head fretting. The results of this study suggest that in vivo corrosion of modular hip taper interfaces is attributable to a mechanically-assisted crevice corrosion process. Larger diameter necks will increase neck stiffness and may reduce fretting and subsequent corrosion of the taper interface regardless of the alloy used. Increasing neck diameter must be balanced, however, with the resulting loss of range of motion and joint stability.

The electrochemical and mechanical behavior of passivated and TiN/AlN-coated CoCrMo and Ti6Al4V alloys.

The mechanical and electrochemical behavior of the surface oxides of CoCrMo and Ti6Al4V alloys during fracture and repassivation play an important role in the corrosion of the taper interfaces of modular hip implants. This behavior was investigated in one group of CoCrMo and Ti6Al4V alloy samples passivated with nitric acid and another group coated with a novel TiN/AlN coating. The effects of mechanical load and sample potential on peak currents and time constants resulting from fracture of the surface oxide or coating, and the effects of mechanical load on scratch depth were investigated to determine the mechanical and electrochemical properties of the oxides or coating. The polarization behavior of the samples after fracture of the oxide or coating was also investigated. CoCrMo had a stronger surface oxide and higher interfacial adhesion strength, making it more resistant to fracture than Ti6Al4V. If undisturbed, the oxide on the surface of Ti6Al4V significantly reduced dissolution currents at a wider range of potentials than CoCrMo, making Ti6Al4V more resistant to corrosion. The TiN/AlN coating had a higher hardness and modulus of elasticity than CoCrMo and Ti6Al4V. It was much less susceptible to fracture, had a higher interfacial adhesion strength, and was a better barrier to ionic diffusion than the surface oxides on CoCrMo and Ti6Al4V. The coating provided increased corrosion and fretting resistance to the substrate alloys.

Enhancing the engineering curriculum: Defining discovery learning at Marquette University

This paper summarizes the results of our investigation into the feasibility of increasing the level of discovery learning in the College of Engineering (COE) at Marquette University. We review the education literature, document examples of discovery learning currently practiced in the COE and other schools, and propose a Marquette COE-specific definition of discovery learning. Based on our assessment of the benefits, costs, and tradeoffs associated with increasing the level of discovery learning, we present several recommendations and identify resources required for implementation. These recommendations may be helpful in enhancing engineering education at other schools.

Active Learning in Capstone Design Courses [Senior Design]

There is a growing trend to encourage students to take a more active role in their own education. Many schools are moving away from the sage on the stage to the guide on the side model where the instructor is a facilitator of learning. In this model, the emphasis is more on learning and less on teaching, and it requires instructors to incorporate more active and student-centered learning methods into their courses. These methods include collaborative, cooperative, problem-based, and project-based learning.

Capstone Design Courses:Producing Industry-Ready Biomedical Engineers

The biomedical engineering senior capstone design course is probably the most important course taken by undergraduate biomedical engineering students. It provides them with the opportunity to apply what they have learned in previous years; develop their communication (written, oral, and graphical), interpersonal (teamwork, conflict management, and negotiation), project management, and design skills; and learn about the product development process. It also provides students with an understanding of the economic, financial, legal, and regulatory aspects of the design, development, and commercialization of medical technology. The capstone design experience can change the way engineering students think about technology, society, themselves, and the world around them. It gives them a short preview of what it will be like to work as an engineer. It can make them aware of their potential to make a positive contribution to health care throughout the world and generate excitement for and pride in the engineering profession. Working on teams helps students develop an appreciation for the many ways team members, with different educational, political, ethnic, social, cultural, and religious backgrounds, look at problems. They learn to value diversity and become more willing to listen to different opinions and perspectives. Finally, they learn to value the contributions of nontechnical members of multidisciplinary project teams. Ideas for how to organize, structure, and manage a senior capstone design course for biomedical and other engineering students are presented here. These ideas will be helpful to faculty who are creating a new design course, expanding a current design program to more than the senior year, or just looking for some ideas for improving an existing course. Contents: I. Purpose, Goals, and Benefits / Why Our Students Need a Senior Capstone Design Course / Desired Learning Outcomes / Changing Student Attitudes, Perceptions, and Awarenesss / Senior Capstone Des gn Courses and Accreditation Board for Engineering and Technology Outcomes / II. Designing a Course to Meet Student Needs / Course Management and Required Deliverables / Projects and Project Teams / Lecture Topics / Intellectual Property Confidentiality Issues in Design Projects / III. Enhancing the Capstone Design Experience / Industry Involvement in Capstone Design Courses / Developing Business and Entrepreneurial Literacy / Providing Students with a Clinical Perspective / Service Learning Opportunities / Collaboration with Industrial Design Students / National Student Design Competitions / Organizational Support for Senior Capstone Design Courses / IV. Meeting the Changing Needs of Future Engineers / Capstone Design Courses and the Engineer of 2020

Standards education in senior design courses

Medical device standards provide many benefits to manufacturers and users of medical devices. Compliance with these standards is necessary to allow companies to market their devices. Standards contain requirements that affect the way medical devices are designed, developed, and tested. Students in biomedical engineering senior design courses need to be made aware of these standards and understand their impact on the design process for medical devices. They need to appreciate the value of considering them early in the design phase of a project. This article discusses how medical device standards education can be incorporated into senior design courses.

The healthcare technologies management program

Developing an engineers awareness of factors that affect the cost of healthcare technology is discussed. It is concluded that the Healthcare Technologies Management Program offered by Marquette University and the Medical College of Wisconsin is a unique program that meets the unique needs of engineers and their employers. The program prepares new graduate engineers to work in hospitals, medical device companies, and consulting firms, and it provides experienced engineers with the training needed for career advancement. It provides several advantages over graduate business and technical degrees and many benefits to students and their employers. The emphasis of the program can play a role in the reduction of the costs associated with the development of healthcare technology.

Capstone Projects and National Student Design Competitions [Senior Design]

National design competitions that focus on solutions to problems in health care benefit students, faculty, academic institutions, medical device industry, and society [1]. They get students excited about becoming engineers and help focus student energy, enthusiasm, and talent on a specific real-world problem. They allow students to showcase the results of their senior-design (and other) projects, providing national exposure that can help when seeking employment after graduation and possible venture funding for promising new technologies.

Senior design - biomedical engineering/industrial design collaboration in senior design projects

To prepare biomedical engineering and industrial design students for potential future collaborations, it would be helpful for them to understand and appreciate the contributions each can make to the project team. This can be accomplished through the senior capstone design course by forming project teams that include biomedical engineering and industrial design students. Collaboration between biomedical engineering and industrial design students on senior design project teams provides many benefits. First, students learn how to communicate with people in other functional disciplines. Second, students learn that no individual person has all the skills and knowledge needed to complete a project, and they develop an appreciation for the complementary skills each member brings to the project. Third, students learn that there is more than one way to solve a problem. This helps them develop an appreciation for different approaches to problem solving and ways of thinking. Finally, the overall quality of product design increases when biomedical engineering and industrial design students work together.

Maintaining a Relevant, Up-­to-­Date Capstone Design Course [Senior Design]

Senior capstone design courses can be extremely helpful in preparing biomedical engineering students for careers in engineering and other fields. They allow students to develop communication, teamwork, and other transferable technical and nontechnical skills. They can also make students aware of the 1) legal, regulatory, economic, environmental, and social/political constraints of medical device design, 2) contemporary issues related to biomedical engineering and health care, and 3) the latest trends and tools in new product development and project management.