Vets Take Joint
Look at Horse Knees
Veterinary teaching module will give students
a 3-D view of equine injuries to aid in diagnosis
Profs. Ludovic Bouré, Clinical Studies, Jeff
Thomason, Biomedical Sciences, and John Runciman, Engineering,
have joined forces to develop a novel veterinary teaching
module designed to give students a three-dimensional virtual
look at a horse's knee.
Equine knee ailments are a common and costly affliction,
says Bouré, who studies laparoscopy and minimally
invasive techniques in large-animal surgery. "It's
a joint that gets a lot of injury. It's frequently injured
in racing horses."
Yet those injuries are notoriously difficult to diagnose
correctly. Holding a skeletal knee, Bouré points
out the intricately detailed grouping of small bones. The
problem is compounded for veterinary students learning to
read a two-dimensional X-ray: Is that hairline a fracture
or just a shadow?
The Guelph team's answer: Why not model that 3-D puzzle
in three dimensions? And rather than stop at the bones,
why not model the surrounding tissues all the way to the
Working with Victor Sprenger, a master's student in biological
engineering, the researchers are developing just such a
3-D computer model, one that Bouré plans to use as
a module in teaching surgical anatomy and arthroscopic principles
to veterinary students.
Work on the module began in 2002 with a two-year $100,000
grant from CANARIE. By fall 2004, the module will be used
along with conventional diagnostic images to help students
learn to pinpoint ailments accurately, Bouré says.
Beyond that, the 3-D computer model might help in surgical
training or be used by vets in planning arthroscopic surgery.
He believes building images and simulations of joint injuries
is less a clinical problem than an engineering challenge.
For his part, Runciman says biological engineers need to
have "a little piece of the clinician inside us"
to understand the nature of problems like this one. "That's
why these collaborative projects work so well."
He and other biomechanical engineers at Guelph have worked
with faculty in OVC and the Department of Human Biology
and Nutritional Sciences on a number of studies.
In the current project, Sprenger is designing the 3-D computer
module, including integrating the structures to enable a
user to virtually dissect a horse's knee joint. Also involved
are University of Montreal professor André Desrochers
and Montreal 3-D artist Félix Roy, who will use colour
and texture to make the image surfaces more realistic. (The
software for the project was also used to produce animations
for the movie The Lord of the Rings.)
On the screen of Sprenger's laptop, a gold-tinted 3-D image
shows the joint's bones and ligaments down to a resolution
of half a millimetre. He built that image by marrying MRI
data acquired at the Lawson Institute in London with information
from a technique developed by the Mississauga firm Applied
Precision and used mostly by carmakers to provide co-ordinates
of millions of points in space down to tenths of millimetres.
Called polarized white light scanning, the technique gave
the Guelph researchers a picture of the surface contours
of the joint and enabled them to map the motion of individual
bones as well as cartilage and ligaments. Undergraduate
engineering student Mark Kwiesinski helped process the MRI
images and scanning data to pull out useful 3-D information.
They ended up with more data than needed. "It has
to look realistic, but it doesn't have to be too realistic,"
He notes that no surgical simulations exist for equine knees.
"Surgical simulators for human knees were one of the
first to be developed because arthroscopic surgery on that
joint is so common."
As an undergraduate, he worked on 3-D motion analysis in
Runciman's biomechanical engineering design course, intended
to give students a look at the science of medical implants
and tools. Sprenger says that work gave him even greater
appreciation of the intricacies of biomechanics, especially
those of the human body - "the greatest engineering
marvel of all."
He's intimately acquainted with the ability of the body
to withstand various forces as a former two-time All-Canadian
wrestler. On the way to winning the Canadian university
championships in 1999 and silver in 2001, he earned his
own share of injuries, including torn ligaments in his ankles
Sprenger planned to become a doctor when he entered U of
G in 1996 as a President's Scholar. Drawn instead to engineering,
he is combining both interests in biological engineering.
Glancing at the image on his screen, he says this project
has given him a different view of biomechanics. "It's