Hampstead Heath this morning was beautiful but treacherous and all of a sudden, as is usual with such things, I fell over on the ice. One minute I was walking along chatting and the next minute I was on my bottom as my wrist, forearm, shoulder and buttock took a bash. I slid sideways fast in the fall, thereby distributing the blow to several parts of my body and reducing its impact, entirely by luck. So I escaped joining the legions of people who, over the UK Christmas festivities, suffered a fall as the weather managed to concoct a particularly tricky combination of sub-zero temperatures and sharp showers.

Falls are an increasing concern as the population of many countries gets older and not just in periods of cold and frosty weather. Our ability to maintain balance is something we take for granted since we learned to walk but it relies on a series of complex skills and abilities which are subject to the changes which come with age. In elderly people falls can become a significant problem, causing injuries and fractures which need costly medical and surgical care and eventually threatening independence. Medical systems all over the world are feeling the expense and the clinical load which results from falls.

The management of our physical equilibrium under challenging conditions demands a number of mental and physical skills to be kept sharp. With age the muscle strength of the limbs reduces steadily and they employ a smaller and smaller joint range of movement in gait. This develops into the typical gait of an older person with the increased frequency of shorter steps and decreased excursion of the leg joints with smaller movements. If suddenly required to accomplish a much larger movement to hold balance they either may have lost the joint movement for this or are unable to make the movement occur within the required time.

Proprioception or joint position sense is a vital ability which continually informs our brains about where the limb and trunk segments are and if they are moving at what speed and in which direction. This unrecognised ability is vital in our holding postures and moving about accurately. Loss of proprioceptive input or more generalised feeling from the whole or part of a limb prevents the brain obtaining crucial information about where the limb is, making it unable to successfully plan moving it somewhere else. The loss of joint position sense or of sensation is of greater importance to function than muscle weakness as gait is possible with weakness as long as position sense is good.

There are several central nervous system capabilities which impact strongly on the ability to keep balance during movement, including the balance organs, vision, mental abilities such as logical thought and awareness and vision. The ability to see well makes us aware of the alterations in the surfaces we face and allows a judgment about which way to move and then to monitor the movement for effectiveness in achieving what we desire. Our balance is greatly worsened by closing our eyes and if we have poor vision and loss of some position sense then this may allow us to be vulnerable to falls.

The balance and coordination pathways in the brain also have to be working well if we are going to react appropriately, with the balance organs in the ears contributing as well as our eyes. If our organs of equilibrium in the ears are affected, perhaps reduced in accuracy or giving us feelings of giddiness when turning our head, then losing our balance can be more likely. A general age-related reduction in the effectiveness of our neural abilities can also affect the cerebellar pathways which deal with coordination.

An important ability in preventing falls is our awareness and our ability to make correct judgments for the conditions. Being aware of what is around us allows us to make early preparations for the challenges to our balance whether they be icy ground, water, unexpected obstacles or other people moving in particular ways. Keeping ourselves alert and mentally active allows us to process all these complex inputs and make the appropriate decisions to maintain our balance at all times.

Jonathan Blood Smyth, editor of the Physiotherapy Site, writes articles about Physiotherapy, back pain, orthopaedic conditions, neck pain, injury management and Leeds Physiotherapists. Jonathan is a superintendant physiotherapist at an NHS hospital in the South-West of the UK.