Comparison of Virtual Reality Therapy and Conventional therapy on upper limb function and Ocular Tracking on individuals with Parkinson's Disease : a single Blind Randomized Control Study

Abstract

Background: Parkinson's disease (PD) is a debilitating progressive neurological disorder. The main clinical features of PD are: rigidity, bradykinesia, akinesia, and resting tremor. People living with PD often present with impaired gross- and fine upper-limb motor control and ocular tracking. The impaired motor control associated with PD results in difficulty performing basic- and instrumental activities of daily living (BADLs and IADLs). Virtual reality (VR) therapy is an emerging treatment strategy used to address movement impairment in people with neurological diseases, but has not been extensively researched in the rehabilitation of people with PD. This study aimed to determine the effectiveness of VR therapy as a treatment modality for the rehabilitation of upper-limb function during BADLs and IADLs and ocular tracking for people with PD, when compared to conventional physiotherapy. Methods: A single blind randomised control trial was done. Participants were randomly allocated to either the conventional therapy (control) or VR therapy (experimental) groups using the concealed opaque envelope method. Twenty-two participants who gave informed consent were included, if they met the following criteria: Confirmed PD diagnoses; scored above 24/30 for the Mini Mental State Examination; and did not suffer from uncontrolled co-morbid diseases. The control- and experimental groups underwent twelve intervention session of 45 minutes. The control group participated in conventional physiotherapy sessions and the experimental group used the X-box Kinect© VR apparatus during treatment. Participants were assessed at baseline and post-intervention (directly following the 12 session) with the: 9 Hole Peg Test (9HPT), Test d'Evaluation des Membres Superieurs De Personnes Agees (TEMPA) and the King Devick Test. Results: The TEMPA was used to determine unilateral- and bilateral upper-limb function during IADLs and BADLs. Three of the four items of the TEMPA that assessed bilateral upper-limb function indicated statistically significant improvement when the difference between the control and experimental groups were compared post-intervention (Task1 p=0.611; Task 2 p=0.0043; Task 3 p=0.0078; Task 4 p=0.0002). Similarly, three of the four items of the TEMPA that assessed unilateral upper-limb function indicated statistically significant improvement for the experimental group, when compared to the control- group post-intervention (Task 5 p=0.0151; Task 6 p=0.4118; Task 7 p=0.0064; Task 8 p=0.0009). The 9HPT assessed in-hand manipulation and fine upper-limb function. Results from the 9HPT for the left- and right hands of both groups showed clinically significant improvements from baseline to post-intervention, but there was no statistically significant difference between the two groups. The King Devick test was used to assess ocular tracking. The comparison of change between the two groups from baseline to post-intervention on the King Devick did not indicate clinically- or statistically significant change. Discussion and Conclusion: The findings from the bilateral IADL and BADL tasks as measured with the TEMPA are similar to findings in the literature. The results show that VR therapy improve motor control of the upper-limb significantly when both hands work together and when the upper-limbs are moving unilaterally. VR therapy might be more effective than conventional physiotherapy because it allowed for repetitive practice of functional activities, which aided the development of limb control and functional muscle strength. The VR therapy also allowed task-oriented training to occur repetitively. Task-oriented training is known to aid neural plasticity and facilitate functional rehabilitation. The insignificant differences between the groups on the 9HPT is an indication that the task performed for this outcome measure is not specific enough to detect hand function and grip strength. The King Devick test did not indicate change for the control- or experimental groups, which indicates that specific ocular tracking exercises should be included in therapy to address this impairment.