When Christa Barr heard about an opportunity to do a summer research project with the professor who taught her favorite class, she jumped at the chance.

Barr, a fourth-year student in the six-and-a-half-year physical therapy program, had taken physical therapy professor David Wallace's Kinesiology class. Wallace selected Barr from a pool of applicants for the eight-week summer research grant program.

"It's a nice opportunity for students to get their hands on some research, an introduction to the world of research," Wallace said.

Their research involved evaluating how hip motion affects knee joint mechanics in patients with total knee replacements. First, they recruited 10 volunteers with normal knees, observing how they walked and the effect that a special hip strap had on the motion of their hips. Next, they needed subjects who had undergone total knee replacements, and could walk without a cane or walker.

For Barr, one of the most challenging aspects of the project was cold-calling potential subjects for the study. Because patients who have had this surgery are often older and not very mobile, it was difficult to convince people to volunteer. "A lot of people turned me down," Barr said.

Eventually, two subjects with total knee replacements signed up for the study. Wallace and Barr plan to recruit additional subjects when they continue their research during the academic year.

When a volunteer came into the motion analysis lab, Barr took measurements of the subject's height, weight and knees. They observed the subject walking with and without the hip strap. The data collection involved placing surface electrodes on the subject's muscles, as well as reflective markers on the knees and legs. With the aid of a computer program, they determined which muscles were firing and how much the knee was bending and rotating while the subject was walking.

Barr says that she enjoyed working one-on-one with Wallace. "He's wonderful to work with, very patient. He's always quick to explain what our research findings meant," Barr said.

It was also a great opportunity to work closely with subjects. "I really liked working with the patients and seeing how our research could benefit them," she said.

Their goal is to be able to present their findings at an American Physical Therapy Association conference and publish in a journal.