Balance

Unfortunately many adults are the victims of falls as they get older; in fact over 150,000 falls are reported in England and Wales every year – and the number is growing. Those falls often result in serious injuries such as fractures that require hospitalisation.  The overburden of costs from falls including rehabilitation and social care are enormous. Additionally the human costs include pain, distress, loss of confidence and independence.

As many as 90% of those with fractured hips never regain their previous level of mobility and independence.

Although there can be a variety of reasons as to the cause of a fall, problems with balance control is often a major contributing factor.

What is balance?

Balance is achieved via the correct interaction of a number of complex anatomical systems including sensation, nerve reaction times and muscle strength and control.

The following chart summarises the different components involved in achieving good standing and walking balance.

balance diagram - independent mobility

Basically you need good quality sensory information from your vestibular system (eyes and ears) as well as nerve sensors in your joints and muscles.

Then you need quick decisions by the brain and spinal cord to instruct the muscles to respond appropriately.

This continues in a constant cycle where you respond to your movement again.

 

How do we balance?

Balance is defined as the body’s ability to maintain its centre of mass (COM) within its limits of stability as determined by its base of support (BOS). When the body’s COM is within its stability limits, the body’s position can be maintained without changing its BOS. Conversely, if the body’s COM moves outside its limits of stability, its BOS must be changed in order to restore stability otherwise balance will be lost and this could ultimately result in a fall.

                  STABLE BALANCE                                                                   UNSTABLE BALANCE

stable and unstable balance diagram

 

 

posture control

 

Improving Balance

*        Balance is affected by the aging process. As we get older, walking becomes slower and in some people, by as much as 15% by the age of 70. The head and torso become morestooped and the shoulders become more rounded. Stride length and arm swing reduce. The body becomes stiffer and there is less rotation at the hips knees and ankles. The base of support reduces and the amount of time spent in ‘double support’ when walking (i.e the amount of time that both feet are in contact with the ground) increases. This is more commonly known as ‘shuffling’. All of these factors reduce balance and increase the risk of a fall.

*        Although exercise to improve muscle strength, balance and functional fitness is known to help prevent falls, many older adults are unable to exercise effectively. WBV can improve muscle strength and balance.

 

References

*        Patient Safety First – NHS

*        McMillan I (2012) “ A passion for preventing falls” in Frontline – the Voice of Physiotherapy, 18(5) p24-7

*        Gillespie L, Robertson M, Gillespie W, Lamb S, Gates S, Cumming R, Rowe B. (2010) Interventions for preventing falls in older people living in the community (Review). The Cochrane Library. 10.

*        Tinetti ME, Speechley M, Ginter SF. (1988) Risk factors for falls among elderly persons living in the community. New England Journal of Medicine; 319:1701–7.

*        Woollacott M & Shumway-Cook A. (1990) Changes in posture control across life span – A systems approach. Physical Therapy. 70 (12): 799-807.

*        Narcís G, Armando Raimund, Alejo Leal. (2006) Low-frequency vibratory exercise reduces the risk of bone fracture more than walking: a randomized controlled trial. BMC Musculoskeletal Disorders;7:92

*        Kovacs C, (2005) Age-related changes in gait and obstacle avoidance capabilities in older adults:  A review. Journal of Applied Gerontology.  24: 21-34.