Why humans fall: the next step to successful balance

Falls are a major health problem in our aging population. Since balance
deficits are the most important risk factor for falls, it is not surprising
that in the population of Parkinson and stroke patients, in whom balance
deficits are very common, the problem of falls is paramount. For the rational
development of therapeutic and fall-prevention strategies it is essential to
understand the complex regulation of balance and the underlying
(patho)physiological mechanisms. In postural control studies, the
state-of-the-art method is to investigate responses to externally applied
balance perturbations. Previous studies usually focused on feet-in-place
balance recovery responses, whereas in real life, it are the stepping responses
that are critical for successful recovery after a perturbation. With the new
*Radboud Falls Simulator* we are able to assess human postural control,
including reactive stepping responses, at the very limits of stability. On the
basis of these assessments we expect to much better understand critical
mechanisms of postural control, and to be able to predict fall risk in daily
life.

In the proposed project we aim to predict falls in daily life and to identify
both aging- and disease-related impairments that underlie impaired postural
control and an increased risk of falling in daily life.

Prospective cohort study

Participants undergo an intake, consisting of a physical examination and a
familiarization session on the RFS, and a balance assessment. During the
balance assessment participants will be exposed to balance perturbations by
sudden translations of the support surface. The risks of participating in the
balance assessment are very small, since rails are mounted around the balance
platform and participants wear a safety harness. After the assessment on the
RFS, participants (in the older and patient groups) will be followed for one
year to monitor their falls in daily life. In addition, their fear of falling
and activity level (recorded by an ambulant registration system) will be
measured every three months during follow-up. A possible benefit for individual
patients may be that we will be able to identify treatable balance impairments.
In this case, patients will be offered appropriate rehabilitation.