Penn State logoParkinson’s disease seems to have held the attention of researchers across the globe for years. Last month, we had reported about stomach hormones decreasing the growth of Parkinson’s. A new research by scientists from the Penn State University reveals that there could be one more indication of Parkinson’s disease namely an irregular arm swing.

Neurologists are of the opinion that irregular arm swings while walking could be early evidence of Parkinson’s disease. They believe that if the disease is detected early, it could help physicians apply treatments to decrease additional brain damage until they can avail of strategies to slow disease progression.

“The disease is currently diagnosed by tremors at rest and stiffness in the body and limbs. But by the time we diagnose the disease, about 50 to 80 percent of the critical cells called dopamine neurons are already dead,” mentioned Xuemei Huang, associate professor of neurology, Penn State Hershey College of Medicine.

For better understanding this criteria, Huang and her colleagues claim to be analyzing gait or the manner in which people walk. This may help them comprehend the physical signs that could be a very early marker for the onset of Parkinson’s. Apparently Huang’s clinical impression has been confirmed by them. It implies that people with Parkinson’s might exhibit asymmetrical arm swing. As a person walks, this means that one arm could swing much less than the other.

“We know that Parkinson’s patients lose their arm swing even very early in the disease but nobody had looked using a scientifically measured approach to see if the loss was asymmetrical or when this asymmetry first showed up,” added Huang. “Our hypothesis is that because Parkinson’s is an asymmetrical disease, the arm swing on one arm will be lost first compared to the other.”

As part of the research, the arm swing of 12 people diagnosed three years earlier with Parkinson’s was compared to eight people in a control group. To avoid influencing the test results, the Parkinson’s patients were required to stop all medication the night before. Armed with special equipment, the team measured movement accurately. This included a number of reflective markers on the participants along with eight digital cameras that captured the correct position of each body part during a walk.

“Images from the cameras were sent to a computer where special software analyzed the data” explained Huang. “When a person walks, the computer was able to calculate the degree of swing of each arm with millimeter accuracy.”

On analyzing the magnitude of the arm swing in addition to asymmetry and walking speed, the research suggested that people with Parkinson’s showed arm swing which had a remarkably greater asymmetry than people in the control group. One arm supposedly swung significantly less than the other in the Parkinson’s patients.

It was further observed that participants who walked at a faster speed exhibited augmented arm swing though the corresponding asymmetry between them was the same. People without Parkinson’s apparently showed slightly irregular arm swing, those suffering from the disease seem to display significantly larger asymmetry.

The findings appear in the current issue of Gait and Posture.