Asymmetrical arm swings may signal Parkinson's disease

Parkinson's disease is a neurodegenerative illness that can have devastating effects on motor skills, including walking. A new study found that arm-swing asymmetry while walking may be one of the first signs of the disease.

In this small study, researchers from University of North Carolina at Chapel Hill and Pennsylvania State University did a gait analysis among 12 older people with early stage Parkinson's disease, and eight people without the disease, who served as a control group. Before gait analysis tests, those in the Parkinson's group tapered off their Parkinson's medication so test results wouldn’t be swayed.

Each participant had the movement of their arms, pelvis and lower extremeties analyzed via a 3-D motion capture system as they walked three ways: at a normal gait, at a fast gait and on their heels, the last to minimize push-off.

The Parkinson's group showed more arm-swing asymmetry than the control group in the normal and fast walking variations. But trunk rotation was basically the same for both groups, showing that it didn't factor into the arm-swing asymmetry. Arm-swing magnitude was the same for both groups as well.

"Our data suggests that this could be a very useful tool for the early detection of Parkinson's," Xuemei Huang, associate professor of neurology at Pennsylvania State Hershey College of Medicine, said in a news release. Huang, the study's co-author, added: "There are wide scale efforts to find drugs that slow cell death. When they are found, they could be used in conjunction with this technique to arrest or perhaps cure the disease because they could be given before great damage has occurred."

The study appears in the current issue of the journal Gait and Posture.

-Jeannine Stein

Photo credit: Don Emmert / AFP/Getty Images