This study demonstrated that the visual and auditory sensor-equipped walker designed for patients with Parkinson's disease freezing of gait (PDF) improved walking and balance. The results showed improvement in the Tinetti Balance and Gait Assessment (TBGA) score and Functional Gait Assessment (FGA) score in the FOG group, while there was an increase in the Timed Up and Go Test (TUGT) time. In Parkinson's disease patients without freezing of gait (PDNF), improvement in the Functional Gait Assessment (FGA) score was observed, accompanied by an increase in walking time in this group.
The existing studies have separately evaluated auditory and visual stimuli in the PDF group, finding that both stimuli contribute to improving walking levels 28–31. Taking these studies into consideration, we have developed a walker for PH that provides these two stimuli and also reduces the risk of falling in daily life.
Technological advancements provide opportunities not only to change the way cues are delivered but also to adapt the content of cues. There is a study reporting that auditory cues are ineffective in individuals with Parkinson's disease experiencing freezing of gait if they do not mimic real walking sounds 32. Therefore, we aimed to provide both
In a study conducted with wearable sensor-equipped garments (smart verbal cues), it has been tested on patients with freezing episodes, indicating that these patients showed less gait deviation 33. However, it has been reported that patients do not particularly prefer to use this smart verbal cue system. Especially, it has been reported that the smart verbal cue system causes fatigue in patients 34. Similarly, in our study, although the cue was found to reduce the risk of falls in patients and increase their ability to adapt to different movements along with walking, it may have caused patients to slow down their walking speed, which could be a reason for them not to use this developed walker.
Postural control and balance 35 were affected more significantly in PD patients with FOG compared with non-FOG group. FOG often occurs when turning also suggests that the postural control impairment probably contributes to freezing. However, whether balance impairment is an accompanying symptom of FOG or a risk factor of FOG remains unclear. We found that the walker we developed reduced the risk of falls in both PDF and PDNF patients, where the risk of falling is a concern.
Janssen et al. (2020) reported that visual stimuli provided through virtual reality did not affect patients' freezing of gait (FOG) and even prolonged turning duration36. Our study similarly found that walking speed decreased in all Parkinson's patients, supporting this finding.
The effect of walking cues in patients with Parkinson's disease has been evaluated in the literature. However, there are few studies that assess the combined effect of both cues. One such study conducted by Suteerawattananon et al. (2004) reported that cues improved walking in Parkinson's disease patients, with visual cues alone improving step length, auditory cues alone improving walking pace, and the combination of both cues being much more effective than cues given individually1. However, this study was not conducted in patients with freezing. Another study conducted in patients with freezing37 evaluated walking by stimulating patients' feet with mechanical pressure applied to the sole, resulting in sensory feedback upon contact with the ground. This study indicated that peripheral stimulation improved walking parameters in patients with freezing.