First they strap on tiny electronic markers -- very precisely placed on the knees and hips.
A receiver hanging from the ceiling picks up signals as people just walk.
"I am going to have you walk here all the way to the far set."
A little difficult to determine any alteration in gait -- until you look at the computer generated image here.
Dr. Kharma Foucher, biomechanics researcher, Rush University Medical Center: "We want to get a sense of what the muscles are doing. We want to get a measurement of what motions the joint is actually doing."
With each step there is force from the ground up through the knees and hips.
Dr. Kharma Foucher: "Your foot hits the ground, your body has to respond, and that's the wear and tear on your joints."
At 48, Kathy Foulser was just beginning to feel the effects.
Kathy Foulser, rush gait study participant: "I was having a little bit of hip pain, not serious enough that it motivated me to go to the doctor."
But that was the perfect time to come to Rush University Medical Center's gait analysis lab where Dr. Kharma Foucher is trying to back up the process of hip osteoarthritis to see what triggers pain and possibly how to prevent it.
Dr. Kharma Foucher: "We are hoping to learn whether there are subtle things in the way that people walk or the way that you move your hips or the way the muscles fire around the hip joints that can tell us whether you might have osteoarthritis, if you have osteoarthritis, how severe it is and down the line if there is specific therapy or type of exercise that might be able to help you."
With more than 300,000 hip replacements every year, Dr. Foucher says she's hoping to prolong activity and surgery for patients.
Dr. Kharma Foucher: "So if we can develop this dynamic functional test and validate that for detecting hip osteoarthritis or detecting these flavors of hip osteoarthritis, then we could provide better care for these patients."
She has noticed a slight hesitation in step at the onset of hip problems, and since x-rays can't tell the real story, this functional figure can.
Dr. Kharma Foucher: "There could be many flavors of osteoarthritis. Some people respond to physical therapy, some people need a completely different intervention. Having that might help us decide what treatment would work for what person to give to prolong the time before they might need a hip replacement to help them maintain their desired level of activity."
Rush researchers are looking for 60 people to join their study. If you'd like to learn more about the study, call (312) 942-5422 or go to the Human Motion Laboratory at Rush University Medical Center: