Triggers for Freezing of Gait in Individuals with Parkinson’s Disease: A Systematic Review

Background Freezing of Gait (FOG) is a motor symptom frequently observed in advanced Parkinson’s disease. However, due to its paroxysmal nature and diverse presentation, assessing FOG in a clinical setting can be challenging. Before FOG can be fully investigated, it is critical that a reliable experimental setting is established in which FOG can be evoked in a standardised manner, but the efficacy of various gait tasks and triggers for eliciting FOG remains unclear. Objectives This study aimed to conduct a systematic review of the existing literature and evaluate the available evidence for the relationship between specific motor tasks, triggers, and FOG episodes in individuals with Parkinson’s disease (PwPD). Methods We conducted a literature search on four online databases (PubMed, Web of Science, EMBASE, and Cochrane Library) using the keywords “Parkinson’s disease,” “Freezing of Gait,” and “triggers.” A total of 128 articles met the inclusion criteria and were included in our analysis. Results The review found that a wide range of gait tasks were employed in gait assessment studies on PD patients. However, three tasks (turning, dual tasking, and straight walking) were the most frequently used. Turning (28%) appears to be the most effective trigger for eliciting FOG in PwPD, followed by walking through a doorway (14%) and dual tasking (10%). Conclusions This review thereby supports the use of turning especially 360 degrees as a reliable trigger for FOG in PwPD. This could be beneficial to clinicians during clinical evaluations and researchers who wish to assess FOG in a laboratory environment.