Over 64,000 Australians have Parkinson’s disease (PD) – and this number is rising along with our aging population. A major problem for patients with PD is postural instability – impairment of the reflexes that maintain upright stance. Most patients with PD will develop postural instability, which causes falls and impairs quality of life. Unfortunately, postural instability is often refractory to treatment including medication and conventional forms of deep brain stimulation.
Deep brain stimulation is a rapidly evolving therapy, where electrical stimulation is applied to specific brain regions via implanted electrodes connected to a battery – akin to a heart pacemaker. A new form of deep brain stimulation, targeting a brainstem structure called the Pedunculopontine Nucleus (PPN), has been found to help gait disturbance in PD. PPN stimulation is also proposed to help postural instability – but the impact is uncertain.
To clarify if PPN stimulation can help patients with postural instability, we have recently conducted a multicentre experimental study. We assessed patients with PD implanted with PPN stimulation (for gait disturbance) – and measured the impact on postural control using objective neurophysiological measures. Postural control was assessed both off and on PPN stimulation and compared to controls. Funding from the Brain foundation will allow us to apply mathematical modelling to this data – to characterise postural instability and assess whether PPN stimulation improves it. These findings could be rapidly ‘translated’ to help patients.