Vestibular Functions and Parkinson's Disease

Efficacy of Osteopathic Manipulative Treatment on postural control in Parkinsonian patients with Pisa syndrome: A pilot randomized placebo-controlled trial

BACKGROUND

Pisa syndrome (PS) is a clinical condition frequently associated with Parkinson's disease (PD). It is characterized by a trunk lateral flexion higher than 10 degrees and reversible when lying. One pathophysiological hypothesis is the altered verticality perception, due to a somatosensory impairment. Osteopathic Manipulative Treatment (OMT) manages fascial-system alterations, linked to somatic dysfunctions. Fascial system showed to be implicated in proprioceptive sensibility.

OBJECTIVE

The aim of the study was to assess OMT efficacy on postural control in PD-PS patients by stabilometry.

METHODS

In this single-blinded trial we studied 24 PD-PS patients, 12 of whom were randomly assigned to receive a multidisciplinary physical therapy protocol (MIRT) and sham OMT, while the other 12 received four OMT plus MIRT, for one month. The primary endpoint was the eye closed sway area assessment after the intervention. Evaluation of trunk lateral flexion (TLF) with DIERS formetrics was also performed.

RESULTS

At one month, the sway area of the OMT group significantly decreased compared to placebo (mean delta OMT - 326.00±491.24 mm2, p = 0.01). In the experimental group TLF showed a mean inclination reduction of 3.33 degrees after treatment (p = 0.044, mean d = 0.54). Moreover, a significant positive association between delta ECSA and delta TLF was observed (p = 0.04, r = 0.46).

DISCUSSION

Among PD-PS patients, MIRT plus OMT showed preliminary evidence of postural control and TLF improvement, compared to the control group.

The Effect of Virtual Reality on the Ability to Perform Activities of Daily Living, Balance During Gait, and Motor Function in Parkinson Disease Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

The study aimed to evaluate the effect of virtual reality on balance, motor function, gait, and the ability to perform activities of daily living in patients with Parkinson disease.

METHODS

We searched Cochran Central Register of Controlled Trials, Embase, PubMed, Wanfang Data, VIP Database, and China National Knowledge Infrastructure from their inception to June 2019. Two authors independently screened articles for inclusion, extracted data, and evaluated quality.

RESULTS

Twelve randomized clinical trials involving 360 patients were included. It demonstrated that virtual reality can improve balance, measured by the Berg Balance Scale (fixed model weighted mean difference = 2.28, 95% CI = 1.39 to 3.16, P < 0.00001); strengthen motor function, assessed by the Timed Up and Go test (fixed model weighted mean difference = -1.66, 95% CI = -2.74 to 0.58, P = 0.003); enhance gait ability, assessed by the 10-Meter Walk Test Time (fixed model weighted mean difference = 0.13, 95% CI = 0.02 to 0.24, P = 0.02) in patients with Parkinson disease. It also showed that virtual reality can improve individuals' ability to perform activities of daily living, assessed by modified Barthel Index (fixed model weighted mean difference = 2.93, 95% CI = 0.8 to 5.06, P = 0.007).

CONCLUSIONS

The findings suggest that virtual reality rehabilitation may be valuable in improving the balance, motor function, gait, and ability to perform activities of daily living in patients with Parkinson disease.

Role of caloric vestibular stimulation in improvement of motor symptoms and inhibition of neuronal degeneration in rotenone model of Parkinson's disease - An experimental study

Objective

Parkinson's disease (PD) is a progressive neurodegenerative disorder. In order to explore a noninvasive treatment of PD, in the current study the authors evaluated the neuroprotective efficacy of caloric vestibular stimulation (CVS) using the rotenone-induced rat model of PD. The rotenone models of PD are gaining attention due to high reproducibility. It is also considered to be an improved model to exhibit the pathogenesis of PD and test the neuroprotective effect of various therapeutic interventions.

Materials and methods

Rotenone was i.p. injected (3 mg/kg body weight) to male Wistar albino rats for 21 days to induce PD. As PD is chronic and progressive in nature, the efficacy of chronic CVS intervention was evaluated for 30 days after inducing PD in rats. Motor symptoms were evaluated by assessing locomotor activity in actophotometer, whereas movement analysis was done using Ludolph test and motor coordination was evaluated using rotarod apparatus. The neurochemical and neuropathological changes were also observed in the corpus striatum of rats.

Results

Rotenone administration showed decreased locomotor activity, motor coordination and general movement associated with significant (P < 0.05) reduction in dopamine content in the corpus striatum. The immunohistochemical analysis revealed a marked decrease in tyrosine hydroxylase (TH) immunoreactivity in striatal neurons indicating the significant loss of dopaminergic neurons in substantia nigra (SN) following rotenone injection. However, chronic treatment with CVS restored the nerve terminals in the striatum from rotenone damage. CVS treatment improved the dopaminergic system function by restoring dopamine content in the striatum. CVS also improved the motor deformities clearly suggesting the neuroprotective function.

Conclusion

The results of the present study suggested CVS to be a safe and simple neuroprotective measure against neurodegenerative changes in PD and a promising noninvasive technique to overcome the motor symptoms associated with it. The findings could be useful for further investigations and clinical applications of CVS in the treatment of PD.

Quantitative Evaluation of a New Posturo-Locomotor Phenotype in a Rodent Model of Acute Unilateral Vestibulopathy

Vestibular pathologies are difficult to diagnose. Existing devices make it possible to quantify and follow the evolution of posturo-locomotor symptoms following vestibular loss in static conditions. However, today, there are no diagnostic tools allowing the quantitative and spontaneous analysis of these symptoms in dynamic situations. With this in mind, we used an open-field video tracking test aiming at identifying specific posturo-locomotor markers in a rodent model of vestibular pathology. Using Ethovision XT 14 software (Noldus), we identified and quantified several behavioral parameters typical of unilateral vestibular lesions in a rat model of vestibular pathology. The unilateral vestibular neurectomy (UVN) rat model reproduces the symptoms of acute unilateral peripheral vestibulopathy in humans. Our data show deficits in locomotion velocity, distance traveled and animal mobility in the first day after the injury. We also highlighted alterations in several parameters, such as head and body acceleration, locomotor pattern, and position of the body, as well as “circling” behavior after vestibular loss. Here, we provide an enriched posturo-locomotor phenotype specific to full and irreversible unilateral vestibular loss. This test helps to strengthen the quantitative evaluation of vestibular disorders in unilateral vestibular lesion rat model. It may also be useful for testing pharmacological compounds promoting the restoration of balance. Transfer of these novel evaluation parameters to human pathology may improve the diagnosis of acute unilateral vestibulopathies and could better follow the evolution of the symptoms upon pharmacological and physical rehabilitation.

Visual self-motion cues are impaired yet overweighted during visual-vestibular integration in Parkinson's disease

Parkinson's disease is prototypically a movement disorder. Although perceptual and motor functions are highly interdependent, much less is known about perceptual deficits in Parkinson's disease, which are less observable by nature, and might go unnoticed if not tested directly. It is therefore imperative to seek and identify these, to fully understand the challenges facing patients with Parkinson's disease. Also, perceptual deficits may be related to motor symptoms. Posture, gait and balance, affected in Parkinson's disease, rely on veridical perception of one's own motion (self-motion) in space. Yet it is not known whether self-motion perception is impaired in Parkinson's disease. Using a well-established multisensory paradigm of heading discrimination (that has not been previously applied to Parkinson's disease), we tested unisensory visual and vestibular self-motion perception, as well as multisensory integration of visual and vestibular cues, in 19 Parkinson's disease, 23 healthy age-matched and 20 healthy young-adult participants. After experiencing vestibular (on a motion platform), visual (optic flow) or multisensory (combined visual-vestibular) self-motion stimuli at various headings, participants reported whether their perceived heading was to the right or left of straight ahead. Parkinson's disease participants and age-matched controls were tested twice (Parkinson's disease participants on and off medication). Parkinson's disease participants demonstrated significantly impaired visual self-motion perception compared with age-matched controls on both visits, irrespective of medication status. Young controls performed slightly (but not significantly) better than age-matched controls and significantly better than the Parkinson's disease group. The visual self-motion perception impairment in Parkinson's disease correlated significantly with clinical disease severity. By contrast, vestibular performance was unimpaired in Parkinson's disease. Remarkably, despite impaired visual self-motion perception, Parkinson's disease participants significantly overweighted the visual cues during multisensory (visual-vestibular ) integration (compared with Bayesian predictions of optimal integration) and significantly more than controls. These findings indicate that self-motion perception in Parkinson's disease is affected by impaired visual cues and by suboptimal visual-vestibular integration (overweighting of visual cues). Notably, vestibular self-motion perception was unimpaired. Thus, visual self-motion perception is specifically impaired in early-stage Parkinson's disease. This can impact Parkinson's disease diagnosis and subtyping. Overweighting of visual cues could reflect a general multisensory integration deficit in Parkinson's disease, or specific overestimation of visual cue reliability. Finally, impaired self-motion perception in Parkinson's disease may contribute to impaired balance and gait control. Future investigation into this connection might open up new avenues of alternative therapies to better treat these difficult symptoms.