Affiliated Faculty

Marla Steinbeck

Marla J. Steinbeck, M.T.(ASCP), Ph.D.

Visiting Research Professor, School of Biomedical Engineering, Science & Health Systems


Curriculum Vitae

Dr. Steinbeck is a Research Associate Professor at Drexel University’s School of Biomedical Engineering, Science, and Health Systems. Her research includes the inflammatory based biological failure modes of total joint replacements of the elbow, spine and hip. Dr. Steinbeck is currently investigating the production of reactive oxygen species (ROS) and nitrogen (RNS) by macrophages after ingestion of UHMWPE wear debris and the role of ROS/RNS in promoting aseptic osteolysis. As an Assistant Professor at Thomas Jefferson University, her research included the association of myeloperoxidase expression and product formation in osteoarthritic patients, oxidative stress promotion of idiopathic arthrofibrosis following total knee replacement, and the involvement of hydrogen peroxide in osteoclast differentiation. As a Postdoctoral Fellow and Instructor at Harvard Medical School, Dr. Steinbeck identified NADPH-oxidase expression and the involvement of reactive oxygen species production in osteoclast-mediated bone resorption in addition to developing a method to quantify singlet oxygen production by neutrophils and macrophages in response to phagocytic stimuli.

Dr. Steinbeck is a member of many professional societies, including American Association for the Advancement of Science, American Society for Matrix Biology, and American Society of Bone and Mineral Research. She also reviews articles for journals including Biochemica Biophysica Acta, Journal of Biological Chemistry, and Clinical Orthopaedics and Related Research.

  • Ph.D., Immunobiology, Iowa State University, 1987
  • M.S., Molecular Cell Biology, Iowa State University, 1983
  • M.T., Medical Technology, St.Lukes Medical Center, 1976
  • B.S., Medical Technology/Chemistry, Wayne State College, 1976
Judd Day

Judd Day, Ph.D.

  • Part-time Research Assistant Professor, School of Biomedical Engineering, Science & Health Systems
  • Managing Scientist, Exponent Inc., Philadelphia Office


Dr. Day is a seasoned biomedical engineer with a broad knowledge base in Medical Device R&D. Dr. Day specializes in both biomechanical testing and computational preclinical evaluation of implantable medical devices, with a special emphasis in orthopaedic devices and the musculoskeletal system. He has experience in regulatory and legal aspects of medical device development including products liability and intellectual property considerations. His research interests include biomechanics of the implant/tissue interface, specifically bone remodeling and the relation between bone strength and its structure. Dr. Day characterizes the in-vivo performance of retrieved medical devices including total joint arthroplasty and cardiovascular implants. He routinely consults in the area of radiographic and medical imaging at both the macro and micro scales, as well as in medical image processing.

Dr. Day is an active member of the Orthopaedic Research Society and is the Task Force Chair for the ASTM Total Shoulder Test Methods for the Arthroplasty Subcommittee. He currently holds an appointment as part time Research Professor for the Department of Biomedical Engineering and Health Systems at Drexel University. Prior to joining Exponent, Dr. Day was a researcher at the Erasmus Medical Center in Rotterdam, The Netherlands, at Rush University in Chicago, IL and at both the Institute for Experimental Clinical Research and the Orthopaedic Research Laboratory of Aarhus University in Denmark.

  • Ph.D., Medical Science, Erasmus University, 2005
  • M.S., Mechanical Engineering, Queens University, Canada, 1997
  • B.S., Mining Engineering, Queens University, Canada, 1992
Richard Underwood

Richard Underwood, Ph.D.

Associate, Exponent Inc., Philadelphia Office


Dr. Underwood specializes in the tribological performance of mechanical systems and has worked on tribology and failure analysis projects in the bearing, steel, power distribution, power generation, automotive, and medical device sectors. His areas of expertise include measurement of wear, measurement, and analysis of surface topography, wear mechanisms, contact mechanics, and failure analysis. He has experience in the area of tribological testing and the design of test apparatus.

Dr. Underwood spent two years as the London Implant Retrieval Centre tribologist and established the protocols for the measurement of wear of explanted metal-on-metal hip components. He has measured the wear and investigated the cause of failure of over 250 explanted (retrieval) hip resurfacings and total hip replacements. He has developed a method for measuring the wear of the taper junctions of modular large head metal-on-metal hips and has investigated the causes of tribocorrosion and wear. His research has focused on the effect of design, manufacturing, lubrication mechanisms, wear mechanisms, and surgical and patient factors on the in-vivo performance of hip systems.

Prior to joining Exponent, Dr. Underwood worked as a researcher at the Tribology Group at Imperial College London. In 2008 he completed a Ph.D. on the effects of lubricant contamination on the performance of rolling element bearings. During his time at the tribology group Dr. Underwood worked on projects investigating failure of high voltage switch equipment, environmental degradation of lubricants, bearing failure in marine water jet propulsion system, and bearing failure in pump equipment on a liquid natural gas carrier. He has measured and analyzed the surface topography for projects as diverse as food technology, gas engine crankshafts, corrosion investigations, and machining trials.

  • Ph.D., Mechanical Engineering Tribology, Imperial College London, 2008
  • M.Eng., Mechanical Engineering, Imperial College London, 2003