One of the most disabling features of Parkinson's disease (PD) is represented by the gait disturbances. Some systematic reviews and meta-analysis have showed that conventional physical therapy might improve gait as well as balance, mobility and functional reach in subjects affected by PD. In addition, several studies and reviews support the effectiveness of external sensory cueing, by means of rhythmic auditory or visual cues, in improving kinematic parameters of gait (gait cadence, stride length, velocity, and postural stability) and the functional performance in people with PD, at least in the short-term. Specifically, cueing refers to the use of temporal or spatial stimuli to regulate movement and facilitate functional performance for individual with motor dysfunction. Basal ganglia act as internal triggers of neuronal activity in the supplementary motor area for well-learned, automatic movement sequences, such as locomotion. This mechanism is damaged in individuals with PD, and external cues may act as an attention resource to compensate the deficient internal rhythm due to basal ganglia dysfunction. Subjects can be coached in concentrating their attention on gait by specific self-prompting instructions or by cues stimulation or a combination of these. Movements generated by the presence of external sensory cues are prompted to use alternative (cortical, parieto-premotor) neuronal pathways which have not been damaged by neuronal degeneration of PD, bypassing the automatic basal ganglia network. Recent studies have provided preliminary evidence that visual cueing based on laser shoes and laser canes may reduce freezing, an established risk for falls, with improvement that can be observed for a variable period of time after rehabilitative intervention. In light of the evidence of effectiveness of cueing, developing wearable devices able to generate cues that match with step and that are effective, easy to use and low cost, would be challenging but very appropriate. The aim of this study was to investigate the non-inferiority of a wearable device producing visual cues (Q-Walk system, QUICKLYPRO s.r.l., Bergamo, Italy) in order to improve gait and balance PD patients, compared to a conventional training (stripes on the floor).

All patients consecutively referred to the Neurorehabilitation Unit of HABILITA between 1st November 2019 and 31th December 2021 were screened. Patient were admitted for outpatients rehabilitation. All particpants could walk independently without walking device. All patients were taking oral administration of levodopa, dopamine agonists, or both, and were evaluated in ON phase.

All the patients gave their written informed consent to take part in the study. The study was approved by the Local Ethics Committee of Bergamo (Reg. Sper. n. 178/19, 11/10/2019) and was carried out in accordance with The Code of Ethics of the World Medical Association (Declaration of Helsinki) for experiments involving humans.

Inclusion Criteria:

• diagnosis of idiopathic PD (defined by the UK Brain Bank Criteria);
• absence of cognitive impairment (Mini-Mental State Examination score ≥ 24);
• Hoehn & Yahr stage II-IV; mild to severe gait disturbance with score ≥2 at the Unified Parkinson's Disease Rating Scale (UPDRS) motor section III;
• stable drug usage since at least 3 weeks.

Exclusion Criteria:

• past history or current presence of neurological conditions other than PD;
• orthopedic or visual disturbances severely impairing walking ability;
• previous deep brain stimulation or other neurosurgery;
• participation in a rehabilitation program within 2 months before the trial and previous use of cues for gait rehabilitation.