Patients with Parkinson’s disease who were scheduled to undergo DBS surgery at Beijing Tiantan Hospital were recruited prospectively from October 2019 to April 2021. Inclusion criteria included: (i) diagnosis of idiopathic Parkinson’s disease according to the UK brain bank criteria; (ii) clinical FOGs can be successfully induced as confirmed by at least one experienced movement disorders neurologist; (iii) FOG reached moderate severity as attested by a Freezing of Gait Questionnaire score >10; and (iv) aged between 50 and 80 years. Patients were excluded if they (i) were unable to walk independently in the OFF-medication condition; (ii) demonstrated severe cognitive impairment making cooperation impossible; or (iii) had prominent tremors [any item of the MDS-Unified Parkinson’s Disease Rating Scale (UPDRS) 3.15–3.18 ≥ 3]. Overall, 16 patients were included in this study. This study was in agreement with the Declaration of Helsinki, approved by the IRB of Beijing Tiantan Hospital (KY 2018-008-01), registered in the Chinese Clinical Trial Registry (ChiCTR1900026601) and conducted under the supervision of an authoritative third party (China National Clinical Research Center for Neurological Diseases). All patients signed written informed consent.
