Changes of biomechanics induced by Equistasi® in Parkinson's disease: coupling between balance and lower limb joints kinematics

Axial disorders, including postural deformities, postural instability, and gait disturbances, are among the most disabling symptoms of Parkinson's disease (PD). Equistasi (R), a wearable proprioceptive stabilizer device, has been proposed as neurological rehabilitative device for this set of symptoms. To investigate the effects of the device on gait and balance, 24 participants affected by PD were enrolled in this crossover double-dummy, randomized, controlled study. Subjects were assessed four times before and after 8 weeks treatment with either active or placebo device; one-month wash-out was taken between treatments, in a 20-week timeframe. Gait analysis and instrumented Romberg test were performed with the aid of a sterofotogrammetric system and two force plates. Joint kinematics, spatiotemporal parameters of gait and center of pressure parameters were extracted. Paired T-test (p < 0.05) was adopted after evidence of normality to compare the variables across different acquisition sessions; Wilcoxon was adopted for non-normal distributions. Before and after the treatment with the active device, statistically significant improvements were observed in trunk flexion extension and in the ankle dorsi-plantarflexion. Regarding balance assessment, significant improvements were reported at the frequencies corresponding to vestibular system. These findings may open new possibilities on PD's rehabilitative interventions.