MONTREAL, Quebec, Canada — With a modified iPod Touch and a special app that tracks their steps, patients with Parkinson's disease (PD) can significantly improve arm-swing and gait disorders using a musical reward system designed to rewire their brains, researchers at the University of Calgary in Alberta, Canada, reported here at the 3rd World Parkinson Congress (WPC).
The result is significant improvement in freezing of gait, a hallmark symptom of PD, senior investigator Bin Hu, MD, PhD, professor of translational neurosciences at the Hotchkiss Brain Institute, told Medscape Medical News.
"A natural strategy like this may not be the ultimate silver bullet, but it's easy, and it's effective. Of course it needs to be confirmed in a larger population," said congress program chair Serge Przedborski, MD, PhD, who was not involved in the research, during an interview.
"This reward-based training addresses freezing, the fear of falling, the lack of arm-swing and shortness of step or gait, and the reason why this is so important is that levodopa often does not improve these features of PD and we don't have good treatment," said Dr. Przedborski, professor of neurology, pathology and cell biology and co-director of the Center for Motor Neuron Biology and Disease at Columbia University, New York, New York.
The training system, called Ambulosono, uses fourth-generation iPod motion-sensing technology and an application called Gait Reminder, designed by Dr. Hu's team. The iPod can be strapped to a leg or arm and triggers music to play or stop depending on whether the patient's pace, stride-length, and arm-swing are adequate and synchronized.
"As you use it, it is associated with a high degree of physiologic arousal and therefore a heightened kinesthetic sense and motor awareness," said Dr. Hu.
"Walking is no longer a boring exercise, but becomes a pleasurable habit. Over time we hope this will not only help patients regain their automatic gait control but also facilitate the compensatory reorganization and plasticity changes in the sensory and motor control networks."
Reward-Based Learning
Unlike most gait training exercises, which bypass the basal ganglia, the Ambulosono system focuses specifically on this area of the brain, which is particularly sensitive to behavioral shaping and reward-based learning, said Dr. Hu.
"The basal ganglia and thalamus are very sensitive to practice, so when you practice there is substantial improvement. And what is interesting is this effect lasts: one patient actually stopped the training for 4 months and the freezing didn't return."
In a pilot study of 46 patients who used the system for 320 days, daily walking time improved from an average of 6.3 to 20.4 minutes, and significant improvement was seen in stride length (10% to 30%) and walking speed (10% to 20%).
"Significant improvements were also reported in terms of gait awareness and the amplitude of arm swings during walking," he reported. "More importantly, a subgroup of subjects reported a marked reduction in fear of falling and increase in confidence."
Dr. Hu's team has also adapted the training system into a clinical tool to quantify the severity of gait disorder and freezing.
The concurrent arm swing-stepping (CASS) test uses the Ambulosono technology to instruct patients in concurrently stepping and swinging their arms on the spot — a divided-attention task that often reveals deficits in movement initiation and coordination.
"Freezing episodes can be difficult to catch during clinic visits especially those triggered by environmental conditions such as narrow hallways or elevators, or when patients are on medication," said Dr. Hu. "Patients can tell you they may freeze under certain conditions, but you rarely have first-hand knowledge about how badly they freeze. The CASS test can help us to detect and quantify the severity of freezing to identify potential candidates for intervention, preferably early in the disease progression."
In a pilot study of 33 patients with PD (mean age, 66.6 years; mean disease duration, 8.1 years), the CASS test used a scoring system to measure arm-leg coordination and gait hesitation while the Falls Efficacy Scale- International (FES-I) was used to assess fall-related self-efficacy.
After controlling for age, sex, and disease duration, the study showed that hesitation/freezing, but not coordination, was a significant predictor of FES-I score (P < .01), reported Dr. Hu.
"Our results indicate that CASS can be used as a simple clinical test to reveal dual task-related movement incoordination, gait hesitation and/or freezing, as well as their relationship with self-reported functional efficacy in PD patients."
The CASS test can give physicians, nurses, and therapists "a more standard and reliable way of assessing freezing and its severity for patients during their clinic visits," he concluded. "We are now in the early stage of implementing CASS at our site."
Dr. Hu says in addition to the University of Calgary location, 2 additional Ambulosono trial sites are currently being set up in Alberta, at the Universities of Edmonton and Lethbridge, with a fourth trial site at the University of British Columbia. Neurologists and physiotherapists can send an email for information about participating.
Individual patients can also email about getting the training system. "We are working to implement a network support system with the Michael J. Fox Foundation and local PD support groups," he said.
Dr. Hu developed the Ambulosono technology but declared no financial conflicts of interest. The University of Calgary handles the patent, from which there is no profit. Patients who are currently enrolled in the Alberta and British Columbia trials are provided with the device and services free of charge. Funding for the study was provided by the Canadian Institutes of Health Research, Alberta Innovations Health Solutions, the Hotchkiss Brain Institute, the Parkinson's Society of Alberta, Alberta Health Services, and the Foothills Movement Disorders Clinic. Dr. Przedborski has disclosed no relevant financial relationships
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