Photo courtesy of the Motion Analysis Lab

Maya walks in the Motion Lab, outfitted with reflective markers that allow a biomechanics instrument to collect data for evaluating a cerebral palsy gait.

U.Va. motion lab yields new data on muscle function

By Catherine Seigerman

Walking is an ability most people take for granted, but it is a complex action that medical researchers are only beginning to understand. At U.Va.'s Motion Analysis and Motor Performance Laboratory, health care personnel are helping children with cerebral palsy improve their walking skills, using new computerized imaging technology, and gaining insights into other muscle problems.

"For the first time, we have the technology to measure the walking patterns of patients with cerebral palsy and musculoskeletal disorders," said Dr. Mark Abel, pediatric orthopedic surgeon and medical director of the motion analysis lab, housed at the Kluge Children's Rehabilitation Center. The information from the technology aids the physicians and therapists in refining patient treatments, including surgery, braces and physical therapy.

The U.Va. Motion Analysis Lab is one of the best-equipped centers of its kind in the United States, Abel said. Its computers record a patient's walking pattern through six high-speed video cameras. Floor-mounted force plates measure pressure from different parts of the foot, and reflective markers hooked to electrodes are taped to the patient. The resulting computer screen image looks like a three-dimensional skeleton walking on graph paper.

"The lab can produce a picture using all the factors that make each person's walking pattern unique, including the angles, pressure and speed of limbs," Abel said.

The lab also measures muscle strength. Lab co-director and physical therapist Diane Damiano has developed individualized muscle strengthening programs for cerebral palsy patients based on information from the lab's special equipment. Damiano's strengthening program is now included in fitness materials she produced with the United Cerebral Palsy Association and the Centers for Disease Control and Prevention.

"For decades therapists never strengthened children with spastic muscles because they believed the muscles would get stiffer," Damiano said. "But we challenged that and did two research studies that showed muscle strengthening improves motor function among children with cerebral palsy to the same degree as surgery."

Three U.Va. studies funded by the National Institutes of Health are focusing on cerebral palsy patients in the motion laboratory. The cerebral palsy studies are also giving U.Va. researchers insights into muscle problems in healthy adults. One adult study is investigating low back pain among loading dock workers.

"Just as children with cerebral palsy have muscle spasms and twitches, the same is true of people with low back pain," Abel said. "If we can measure how the spinal vertebrae and back muscles work and why they wear down, a spine therapist will be able to target those areas better."

Another study is investigating muscle fatigue in women athletes. Abel said the muscle measurement techniques for this study grew out of the lab's research on muscle capacity in children with cerebral palsy.