Freezing of gait (FOG) is one of the most debilitating symptoms of Parkinson’s disease, characterised by sudden, brief episodes in which the feet appear to be glued to the floor despite the intention to walk. FOG typically occurs at doorways, when turning, when approaching a destination, or under conditions of cognitive or emotional stress.
How Common Is Freezing of Gait?
FOG affects approximately 47% of people with Parkinson’s disease overall, rising to around 80% in those with more advanced disease. It is strongly associated with falls — people with FOG have a significantly increased risk of falling compared to those without.
Why Does Freezing Happen?
Current models suggest that FOG arises from a breakdown in the automatic execution of gait, forcing reliance on a compromised basal ganglia system that cannot generate the rhythmic motor programme required for continued walking. Cognitive load, anxiety, and fatigue all exacerbate this breakdown.
Cueing Strategies
The most well-evidenced physiotherapy intervention for FOG is the use of external cues — auditory, visual, or somatosensory stimuli that bypass the deficient internal cueing system. Auditory cueing using a metronome or rhythmic music has been shown to improve gait speed, step length, and cadence, and to reduce the frequency of FOG episodes. Visual cues such as lines on the floor or laser light devices provide a visual target for step initiation. The RESCUE trial demonstrated significant improvements in gait and FOG with a cueing training programme delivered by physiotherapists.
References
Nieuwboer, A. et al. (2007). Cueing training in the home improves gait-related mobility in Parkinson’s disease: the RESCUE trial. Journal of Neurology, Neurosurgery & Psychiatry, 78(2), 134–140. https://doi.org/10.1136/jnnp.2006.097923
Nutt, J.G. et al. (2011). Freezing of gait: moving forward on a mysterious clinical phenomenon. Lancet Neurology, 10(8), 734–744. https://doi.org/10.1016/S1474-4422(11)70143-0
Lim, I. et al. (2005). Effects of external rhythmical cueing on gait in patients with Parkinson’s disease: a systematic review. Clinical Rehabilitation, 19(7), 695–713. https://doi.org/10.1191/0269215505cr906oa
Thaut, M.H. et al. (1996). Rhythmic auditory stimulation in gait training for Parkinson’s disease patients. Movement Disorders, 11(2), 193–200. https://doi.org/10.1002/mds.870110213
