Apr 3 2005
Take the kinds of movie techniques that allow animation with true-life action, throw in an anatomically-based muscle, ligament, tendon, bone and soft-tissue geometries dataset, and add individual patient MRI or CT scan data.
What you have is a powerful tool to direct and then check surgical procedures, with the potential to study the effects of drug therapy and disease on a specific physiological system and throughout the body.
In the knee/patella area, researchers at the Auckland University Bioengineering Institute developed a patella articulation knee computer model that successfully showed reductions in kneecap strain that matched earlier literature. Two studies involved corrective procedures to reduce cartilage stress and another assessed literature on surgical outcomes of muscle length changes for children with cerebral palsy.
The work done by Justin W. Fernandez and Peter J. Hunter in Auckland, New Zealand is part of the International Union of Physiological Sciences (IUPS) Physiome Project, which helped develop the modeling framework to investigate soft tissue and general musculo-skeletal problems. Using the physical geometries and characteristic responses of tissues to loading, computers calculate the forces and contact stresses at the joints, a patient-specific profile is generated using morphing techniques based on the individual’s magnetic resonance or computed tomography data.
*Paper presentation: “An anatomically based patient specific model of patella articulation: Towards a diagnostic tool,” 12:30 p.m.-3 p.m. Tuesday April 5, Physiology session/abstract: 902.15; board #A15. On view 7:30 a.m. - 4 p.m. Hunter is presenting the research at the 35th Congress of the IUPS in San Diego, March 31 - April 5, 2005. Prior to the IUPS Congress, the Physiome Project will hold a satellite meeting in San Diego, March 28-30, “Computational physiology: from genome to physiome.”
Reducing cartilage stress points: toward future applications in diagnosis
The two model procedures being reported in San Diego involved reducing cartilage stress. High joint stress can lead to general knee pain and osteoarthritis. That logically leads to the next step with this approach which is to serve as a diagnostic tool, surgical aid and clinical outcome measurement. Those steps would link the current modeling framework at the organ level with the underlying cell level microstructure overlaid with still digital and moving images of the individual patient.
“Eventually, modeling across spatial scales will allow us to extend the model’s scope to investigate the effects of disease and drugs and their effects on the whole body,” Hunter said.
In the other main application so far, “Our full knee model has also been used to assess literature describing muscle length surgery for children with cerebral palsy,” Fernandez noted. “Our model presents virtual simulation of a subject walking, showing joint angles and muscle lengths, while comparing this with the normal population.”
Funding: The Fernandez-Hunter research was funded by a Bright Future scholarship and a New Zealand New Economy Research Fund grant. Fernandez is now a research fellow at the Department of Mechanical and Manufacturing Engineering, University of Melbourne, Australia.