An Open Invitation to the Musculoskeletal Modeling Research Community:

We would like to invite you to participate in the second "Grand Challenge
Competition to Predict In Vivo Knee Loads" to be held at the 2011 ASME
Summer Bioengineering on June 22-25 in Farmington, Pennsylvania

Thanks to funding provided by the National Institute of Biomedical Imaging
and Bioengineering at the National Institutes of Health, we will be hosting
the Grand Challenge Competition at the ASME Summer Bioengineering Conference
for four more years.

The goal of the competition is to evaluate quantitatively model-based
estimates of muscle and contact forces in the knee during gait using in vivo
tibial contact force data collected from subjects implanted with
force-measuring knee replacements. Competitors will use any musculoskeletal
(or other) modeling software and methods they desire to estimate medial and
lateral tibial contact forces for two specified gait trials WITHOUT knowing
the actual contact force measurements. Data files containing predicted
medial and lateral contact forces will be submitted with each competition
abstract. Abstracts will be judged using standard ASME Summer Bioengineering
Conference criteria along with two additional criteria: Accuracy and
Novelty. The highest scoring abstracts will be presented in a special
session at the conference. At the end of the session, the in vivo contact
force measurements will be revealed, and lessons learned by the competitors
will be discussed. The winner of the competition will be announced at the
conference awards ceremony.

The research team has updated the existing project
( to provide all of the necessary
information and data for the second competition. All data collection and
distribution have been IRB approved. Some in vivo contact force data are
included with the data sets to assist competitors in developing their
musculoskeletal models.

If you would like to stay informed about the competition, please sign up for
the "kneeloads-news" mailing list on the competition's project
(under Advanced->Mailing Lists). You will automatically be asked to join
this mailing list any time you download data or documents for the
competition (under Downloads). If you encounter any problems with the data,
or if you have any questions, we will be using the Public Forum feature of (under Advanced ->Public Forums->open-discussion) as a central
location for researchers to post their inquiries and for the research team
to respond.

Last year, research teams from six countries participated in the
competition. We hope to have even broader participation for the second
competition. We look forward to having researchers from around the world
take our challenge to see how well they can predict in vivo knee loads
during gait.


B.J. Fregly, Ph.D., University of Florida

Darryl D'Lima, M.D., Ph.D., Shiley Center at Scripps Clinic

Thor Besier, Ph.D., Stanford University

David Lloyd, Ph.D., University of Western Australia

Marcus Pandy, Ph.D., University of Melbourne