Postural instability is typical in the later stages of the disease, leading to impaired balance and frequent falls,[1] and secondarily to bone fractures, loss of confidence, and reduced mobility.[39] Instability is often absent in the initial stages, especially in younger people, especially prior to the development of bilateral symptoms.[40] Up to 40% of people diagnosed with PD may experience falls and around 10% may have falls weekly, with the number of falls being related to the severity of PD.[4]