Instrumental or Physical-Exercise Rehabilitation of Balance in Parkinson's Disease? (IPER-PD)

We hypothesized that rehabilitation specifically addressing balance in Parkinson ́s disease patients might improve not only balance, but locomotion as well. Two balance training protocols (standing on a moving platform, and traditional balance exercises) were compared by assigning patients to two groups: moving platform (n=15) and balance exercises (n=17). Platform moved periodically in antero-posterior, latero-lateral and oblique direction, with and without vision in different trials. Balance exercises were based on Otago Exercise Program. Both platform and exercises sessions were administered from easy to difficult. Outcome measures were: a) balancing behaviour, assessed both by index of stability (IS) on platform and by Mini-BESTest, b) gait, assessed both by baropodometry and by Timed Up and Go (TUG) test. Falls Efficacy Scale-International (FES-I) and Parkinson's Disease Questionnaire (PDQ-8) were administered. Both groups exhibited better balance control, as assessed both by IS and by Mini-BESTest. Gait speed at both baropodometry and TUG also improved in both groups. Scores of FES-I and PDQ-8 showed a marginal improvement. A four-week treatment featuring no gait training, but focussed on challenging balance tasks produces considerable gait enhancement in mildly to moderately affected patients. Walking problems in PD depend on postural instability and are successfully relieved by appropriate balance rehabilitation.

The importance for training balance in connection with rehabilitation aimed at improving gait is easily stressed by considering the complex motor behaviour underpinning more challenging conditions than linear walking, as walking-and-turning, where the turn-related changes in feet, trunk and head movements are integral part of he kinematics of the steering body (Courtine and M. Schieppati, 2003; Crenna et al, 2007). It is no wonder that freezing of gait and increased risk of falling (Schlenstedt et al., 2016) is associated with abnormal bilateral coordination and turning. Hence, the present investigation somehow diverges from the theory of the task-specific training (Bayona et al., 2005), but considers instead the relevance for locomotion enhancement of training balance control, by hypothesising that specific balance rehabilitation might be sufficient for gait improvement. Here, we trained PD patients with two different treatments, both specifically addressing balance. A platform onto which subjects stood moved in antero-posterior, latero-lateral and diagonal direction in the horizontal plane. A simpler moving-platform protocol had been previously exploited for testing and enhancing balance capacities in patients with PD and with vestibular deficit (Nardone et al., 2010; De Nunzio 2007). This platform protocol challenges both the anticipatory and the reactive capacities to the ongoing postural perturbations, thereby training dynamic balance control, aiming at the balance problems encountered during every day activity. The outcome of the platform treatment was compared to that obtained in another group of matched patients with PD by standardized and validated exercises aimed at training balance and dynamic balance (Renfro et al., 2016). Of note, these exercises contained no dynamic component (i.e. gait-related exercises) of balance training, contrary to Conradsson et al. 2017. Both treatments (platform and exercises) were tailored to the patient individual capacities, and their difficulty gradually increased all along the duration of the treatment (Conradsson et al., 2017). In this context, we estimated any improvement in balance control by indexes of dynamic stability during a balance perturbation test on the mobile platform and by clinical scores related to dynamic balance control. Gait improvement was both evaluated instrumentally and assessed by a functional clinical test.