Balance

Balance: Definition

Balance is a multidimensional process and is the result of interactions between the individual, the task, and the environment. —ANNE SHUMWAY-COOK

Normal Postural Control (Balance)

Balance requires keeping the “Center of Mass” (COM) over the “Base of Support” (BOS) during static and dynamic situations.

Neural components of postural control: Sensory processes

visual, vestibular, somatosensory Central processing

a higher-level integrative process Effector component

sometimes referred to as the neuromuscular component

postural alignment, ROM, muscle force, power & endurance

This system has 3 categories of sensory inputs into our brain to provide spatial orientation cues: Visual: (from the eyes).

Vestibular: Two types of sensors in the inner ear. Rotation sensors in the semicircular canals, provide our sense of head turning. Gravity sensors in the otolith organs, provide our sense of which way is straight down, like a plumb line.

Somatosensory (body sense): Pressure and muscle sense from the skin and extremities.

How Common is Visual impairment?

Impaired vision is highly prevalent and commonly

unreported in the elderly population

Keane EM, O’Connor M, Coakley D, Walsh JB. Eye screening in the elderly. Ir Med J 1997; 90: 141–2.

In a screening study of the senior citizens in the community, the visual acuity was measured with a standard Snellen’s chart.

Nearly 72% had impaired vision. There was a significant association between visual

impairment and female sex, history of diabetes or glaucoma, cataract, infrequent eye examination

Wun YT, Lam CC, Shum WK. Impaired vision in the elderly: a preventable condition. Fam Pract 1997; 14: 289–92.

A North London Study of 1547 people showed that 30% of the sample population aged 65 years and older were visually impaired (less than 6/12) in both eyes and

More than 72% of this bilateral visual impairment could potentially be improved by surgery or spectacles

Reidy A, Minassian DC, Vafidis G et al, Prevalence of serious eye disease and visual impairment in a North London population: population-based, cross sectional study. BMJ 1998;316: 1643-1646

In a recent study visual acuity was measured in population based nationwide samples of British elderly people.

Such measurements were carried out in the context of the national diet and nutrition survey (NDNS) of people aged 65 years or over.

NDNS participants were visited at their home by a nurse who measured visual acuity at 3 meters, using the Glasgow acuity card (GAC) method.

Prevalence of visual impairment increased significantly with age (65–74 years 3.1%; 75–84 years 11.6%; 85 years + 35.5%, ( p-0.001).

Visual Impairment and Fall