Source: UBC Okanagan campus.

UBC researchers Jenn Jakobi and Gareth Jones, both Health and Exercise Sciences professors at UBC’s Okanagan campus, recently completed a study that examined the methods used to monitor the progressive advancement of Parkinson’s disease (PD)–a degenerative disease that affects the central nervous system.

The study compared results from electromyography assessments of leg and arm muscles to basic physical performance tests such as gait speed, balance and hand-grip strength. The results were surprising.

“It became very clear that the hand-grip test was one of the functional tests that proved to be a reliable and valuable test measure,” says Jakobi. “The hand-grip test is an easy and conclusive way to test muscle strength decline in this group of people.”

The study involved 23 men and women with PD and 14 people without the disease, all 50 years or older living independently in Kelowna. The participants wore a portable monitoring device to measure muscle activity with the device recording electrical activity of muscles in the arms and legs for approximately eight hours. Participants also underwent three physical function tests–hand-grip, gait and balance–each morning and afternoon.

Jones says the data gleaned from the three physical tests was as conclusive and as informative as the lengthy recordings of muscle activity. And the tests were easier for participants and those administering the experiments.

“The hand-grip dynamometer is a tool that is easily accessible, easy to use, and is reliable,” says Jones. “In addition they are readily available to health professionals such as family doctors, community therapists and physiotherapists.”

“It seems these devices have come full circle and are back being used by clinicians,” adds Jakobi. “It’s a tool that is ideal for Parkinson’s patients as you can easily record a decline in an individual’s physical strength and function as the disease progresses.”

Patients with PD suffer symptoms like uncontrollable shaking, slowness of movement, and eventually difficulty with balance, coordination and walking. It’s important for health care professionals to track early functional decline of Parkinson’s patients, says Jakobi. In this way, individual health can be monitored and future falls related to the disease prevented.

According to Statistics Canada more than 67,000 Canadians are living with Parkinson’s today, and it is mostly diagnosed in men over the age of 45.

The study was recently published in the journal Archives of Physical Medicine and Rehabilitation.

Funding: Funding provided by Canadian Institutes of Health Research, Institute of Neurosciences, Mental Health and Addiction, Parkinson Society Canada.

Source: Patty Wellborn – UBC Okanagan Campus
Image Source: NeuroscienceNews.com image in the public domain.
Original Research: Abstract for “Handgrip Strength Related to Long-Term Electromyography: Application for Assessing Functional Decline in Parkinson Disease” by Gareth R. Jones, Kaitlyn P. Roland, Noelannah A. Neubauer, and Jennifer M. Jakobi in Archives of Physical Medicine and Rehabilitation. Published online November 5 2016 doi:10.1016/j.apmr.2016.09.133

Abstract

Handgrip Strength Related to Long-Term Electromyography: Application for Assessing Functional Decline in Parkinson Disease

Objective
To determine which clinical measures of physical function (ie, gait, balance, and grip strength) best represent long-term electromyography in persons with Parkinson disease (PD) compared with those without PD.

Design
Cross-sectional study.

Setting
Local community.

Participants
A sample (N=37) of men and women with PD (n=23) and those without PD (n=14), living independently at home, older than 50 years of age, from the local community.

Interventions
Not applicable.

Main Outcome Measures
Measures of gait, balance, and grip strength were completed, and electromyography was examined in biceps brachii, triceps brachii, vastus lateralis, and biceps femoris during a 6.5-hour day. Muscle activity was quantified through burst in electromyography (>2% of the normalized maximum voluntary exertion with a continuous activity period of >0.1s). Stepwise multiple regression models were used to determine the proportion of variance in burst characteristics explained by clinical measures of physical function in PD.

Results
Grip strength was the best predictor of muscle activity in persons with PD (R2=.17–.33; P<.04), whereas gait characteristics explained muscle activity in healthy controls (R2=.40–.82; P<.04).

Conclusions
Grip strength could serve as an effective clinical assessment tool to determine changes in muscle activity, which is a precursor to functional loss in persons with PD.

“Handgrip Strength Related to Long-Term Electromyography: Application for Assessing Functional Decline in Parkinson Disease” by Gareth R. Jones, Kaitlyn P. Roland, Noelannah A. Neubauer, and Jennifer M. Jakobi in Archives of Physical Medicine and Rehabilitation. Published online November 5 2016 doi:10.1016/j.apmr.2016.09.133