Tribology Laboratory

Faculty working on a new invention

The Tribology Laboratory of the Department of Orthopedic Surgery is focused on understanding the friction, lubrication, and wear of natural and artificial joints. To do this, we use mechanical testing machines that simulate the forces and fluid environment our joints experience as we move.

Our work

Osteoarthritis is caused by the slow degradation of protective cartilage on articular bone. This chronic disease affects millions of Americans, and in many advanced cases, requires a replacement of the natural with an artificial joint to regain mobility and decrease pain. By studying how cartilage reacts when it becomes damaged, and by simulating how artificial joint materials (metals, polymers, ceramics) behave in the body, our researchers seek to gain new insights into the progression of osteoarthritis, and how implant materials can be improved.

Currently our group is involved in the following:

  • Total knee arthroplasty wear simulation and modeling
  • Wear characterization of surgically-retrieved knee implants
  • Wear-testing of ankle joints
  • Development of new methods to measure polymer wear of artificial joints
  • Characterizing taper tribocorrosion of hip joints
  • Understanding the tribochemical process of fretting corrosion on metals
  • Observing the biochemical response of cartilage tissue from simulated wear
  • Using experimental results to improve computer models of implant wear


tribology lab reseacher working

The Tribology Lab has the capability to run several wear tests concurrently. Some of our equipment includes:

  • Two knee/ankle motion simulators by EndoLab GmbH
  • A multifunction spine and hip simulator from EndoLab GmbH
  • Ortho-POD pin-on-disc simulator from AMTI, Inc.
  • Custom four-station hip joint simulator
  • Custom fretting corrosion simulator
  • Custom cartilage damage impactor
  • Custom cartilage wear simulator
  • High-pressure material aging chamber
  • Ti-950 nanoindenter from Hysitron, Inc.
  • Cary 670 FTIR spectrometer from Agilent Technologies
  • NewView 6300 3D optical surface profiler from Zygo Corporation
  • Flash 250 SmartScope laser coordinate measuring machine from OGP, Inc.

Key publications

Liao, Y., Pourzal, R., Wimmer, M.A., Jacobs, J.J., Fischer, A., and Marks, L.D. (2011) Graphitic tribological layers in metal-on-metal hip replacements. Science 334:1687-90

Schwenke, T., Wimmer, M.A. (2013) Cross-shear in metal-on-polyethylene articulation of orthopaedic implants and its relationship to wear. Wear 301(1-2):168-174

Knowlton, C.B. Wimmer, M.A. (2013) An autonomous mathematical reconstruction to effectively measure volume loss on retrieved polyethylene tibial inserts. J Biomed Mater Res- Part B101(3):449-57

Zahedmanesh, H., Stoddart, M., Lezuo, P., Forkmann, C., Wimmer, M.A., Alini, M., Van Oosterwyck, H. (2014) Deciphering mechanical regulation of chondrogenesis in fibrin-polyurethane composite scaffolds enriched with human mesenchymal stem cells; a dual computational and experimental approach. Tissue Engineering (Part A) 20:1197-212.

Ngai, V., Wimmer, M.A. (2015) Variability of TKR knee kinematics and relationship to gait kinetics: Implications for total knee wear. Biomed Res Int, 2015: 284513

Mathew, M.T., Nagelli, C., Pourzal, R., Fischer, A., Laurent, M.P., Jacobs, J.J. and Wimmer, M.A., 2014. Tribolayer formation in a metal-on-metal (MoM) hip joint: An electrochemical investigation. Journal of the mechanical behavior of biomedical materials, 29, pp.199-212

Laurent, M.P., Pourzal, R., Fischer, A., Bertin, K.C., Jacobs, J.J. and Wimmer, M.A., 2011. In Vivo Wear of a Squeaky Alumina-on-Alumina Hip Prosthesis. J Bone Joint Surg Am, 93(7), p.e27

Laurent, M.P., Johnson, T.S., Crowninshield, R.D., Blanchard, C.R., Bhambri, S.K. and Yao, J.Q., 2008. Characterization of a highly cross-linked ultrahigh molecular-weight polyethylene in clinical use in total hip arthroplasty. The Journal of arthroplasty, 23(5), pp.751-761

Pourzal R, Knowlton CB, Hall DJ, Urban RM, Laurent MP, Wimmer MA. How does Wear Rate compare in Well-Functioning Total Hip and Knee Replacements? A Postmortem Polyethylene Liner Study, Clinical Orthopaedics and Related Research, DOI 10.1007/s11999-016-4749-8

Lundberg HJ, Ha NQ, Hall DJ, Urban RM, Levine BR, Pourzal R. Contact Mechanics and Plastic Deformation at the Local Surface Topography Level after Assembly of Modular Head-Neck Junctions in Modern Total Hip Replacement Devices, ASTM International (2015), STP 1591: 59-82

Pourzal R, Cichon R, Mathew MT, Pacione C, Fischer A, Hallab NJ, Wimmer MA. Design of a tribocorrosion bioreactor for the analysis of immune cell response to in-situ generated wear products (2014), Journal of Long Term Effects of Medical Implants, 24(1): 65-76

Lundberg HJ, Wimmer MA. Computational Framework for Determining Patient-Specific Total Knee Arthroplasty Loading, Journal of Medical Devices, 7(4):040904-1, 2013 Dec PMCID: PMC4023849.

Lundberg HJ, Knowlton C, Wimmer MA. Fine Tuning Total Knee Replacement Contact Force Prediction Algorithms using Blinded Model Validation. Journal of Biomechanical Engineering, 135(2):021015, 2013 Feb. PMCID: PMC3627216.

Lundberg HJ, Foucher KC, Andriacchi TP, Wimmer MA. Direct Comparison of Measured and Calculated Total Knee Replacement Force Envelopes during Walking in the presence of Normal and Abnormal Gait Patterns. Journal of Biomechanics, 45(6):990-996, 2012 Apr. PMCID: PMC3310338.

Lundberg HJ, Ngai V, Wimmer MA. Comparison of ISO Standard and Total Knee Replacement Patient Axial Force Profiles during the Stance Phase of Gait. Proceedings of the Institution of Mechanical Engineers, Part H, Journal of Engineering in Medicine, 226(3):227-234, 2012 Mar. PMCID PMC3384520.


Our work is made possible by funds from the National Institutes of Health, corporate, and philanthropic research grants and the Department of Orthopedic Surgery.

  • NIH R01-AR059843
  • NIH R03-AR064005
  • NIH R03-AR066829
  • NIH R01-AR066635
  • Orthopaedic Research Education Foundation

Our team

Visiting scholars

  • Alfons Fischer, Prof. Dr.-Ing., University of Duisburg-Essen, Germany
  • Joachim Kunze, Dipl.-Ing., Hamburg University of Technology, Germany
  • Mathew T. Mathew, PhD, University of Illinois, College of Medicine at Rockford

Graduate students

  • Robert Trevino, Graduate College, Rush University
  • Chris Knowlton, Department of Bioengineering, University of Illinois Chicago
  • Steven Mell, Graduate College, Rush University
  • Jacqueline Simon, Graduate College, Rush University

Visiting students

  • Daniel Janssen, Industrial Engineering, University of Duisburg-Essen, Germany
  • Diane Sakarovitch, General Engineering, Ecole Centrale Lyon, France
  • Taylor Holcomb, Materials Science and Engineering, Cornell University

Contact us

For inquiries, please contact Spencer Fullam.