Safety on stairs
Investigator
Constantinos Maganaris, Manchester Metropolitan University
Team
Vasilios Baltzopoulos, Manchester Metropolitan Universtiy
Consultant
Mike Royce, British Research Establishment
Background
Falls are a major problem in old age, and the majority of falls occur during stair descent. This is because the downward movement of the body has to be halted every time the foot hits the step and our ability to do this depends on many factors, including muscle strength, joint mobility and our sense of balance, all of which deteriorate with age.
Older individuals may be unable to generate the muscle forces required to support the body on the upper step or to control the motion when landing on the lower step, especially if the step-rise is high.
On the other hand, if the step-going is small (as is often the case in older homes), the ball of the foot of the lead leg will be placed towards the front edge of the step during descent, risking a slip.
Motor control and balance deteriorations with old age could amplify the problem and a systematic study of stepping errors and how they vary in younger and older participants as the rise and going are changed is required.
One other approach for minimising the risks of falls is to improve the competence and confidence of the individual so that they can cope better with the demands of the built environment. Muscle strength and joint flexibility can be significantly improved by specific training at all ages, as so can balance and motor skills.
However, wide-scale training programmes may not translate into improvements in tasks such as stair descent and a more effective approach would be to design targeted training programmes based on individual specific needs.
Aims and objectives
The overall aim of this programme was to understand the role played in stepping performance by musculoskeletal and sensory functions and their deterioration with ageing and to find ways of improving the ability of older people to descend stairs.
To achieve this, the specific objectives were
to quantify the impact that factors such as deteriorating muscle strength, joint flexibility, balance and motor control have on the ability to safely descend stairs in old age
to identify the optimum design of stairs for safe negotiation by elderly people
to determine the extent to which the identified biomechanical and physiological constraints on stair descent can be minimised with “tailor-made” exercise interventions.
Design
Methods
Three studies addressed these points.
Study 1 identified the contribution that biomechanical factors such as muscle strength and range of motion make to safe stair descent. Study 2 examined the design of stairs to see if changing the going and rise matches better the capabilities of elderly people and improves safety when they negotiate stairs. This study also identified individuals who may have biomechanical limitations and those where motor control and coordination are the main problems. The final Study 3, took subjects, identified in Study 2 as having either biomechanical limitations or problems with balance and coordination, and provided appropriate training to see how effective this is and to what extent it might be used on a larger scale.
Fifty older participants (>65 y), including individuals with a history of falls, and fifty younger participants ( < 40 y) were tested on a staircase with adjustable step-going and step-rise, previously used by our consultant at the BRE.
For Study 1, the staircase was implemented with force plates, and kinematic data was recorded with an optoelectronic system. The measured joint angles and the calculated forces during the descent tasks were compared with values of maximum force and maximum range of motion in isolated tests, so that indexes of muscle strength and joint mobility reserves can be quantified.
In Study 2, the optimum combination of step-rise and step-going was identified from analysis of the kinematic data, quantifying stepping errors such as missteps, hesitations, use of handrail and glances at feet. Fear of falling was assessed from questionnaire scores.
In Study 3, older individuals for whom an increased step-rise causes difficulties were identified. They were considered as having mainly musculoskeletal problems and they underwent eight weeks of knee and ankle muscle strengthening and ankle joint flexibility.
Older individuals with difficulties in reduced step-going values were considered as having mainly motor control and balance problems and they performed eight weeks of balance training and stair descents with corrective feedback and supervised practice.
The two exercise groups were re-tested on the BRE stairs after completion of their training using stair settings identified as “challenging” when first tested to see whether the “tailor-made” interventions were effective.
Outcomes
At the end of the project, we could recommend the optimum combination of going to rise for older people. Such recommendations could become part of the general building regulations and have a significant impact on the physical safety and the confidence of older people.
The outcome of Studies 1 and 2 identified the relative importance of a range of biomechanical and physiological factors that adversely affect stepping performance. This information informed the nature of the interventions outlined in Study 3.
Study 3 indicated the extent to which training for strength, flexibility, balance or motor skills can improve performance. This information is essential for any cost/benefit analysis of possible future large-scale population-based interventions.
Policy implications
Falls, and fear of falling, are major factors affecting the mobility and quality of life for the elderly, and it is descending steps and stairs in the home, gardens, public spaces and on public transport, where problems occur most frequently.
The aim of our project was to find ways of improving the competence and confidence of older people when descending steps and stairs.
Our programme of work met the primary NDA objective to “develop practical policy and implementation guidance along with novel scientific, technological and design responses to help older people enjoy better quality lives.”
We addressed a major problem for older people. Our approach to this question was novel and multidisciplinary in that it touched on the perceptions and fears of falling, and examined the involvement of biomechanical and motor control factors, as well as stair-design aspects.
Our findings may lead to the implementation of policy in the shape of new building regulations through our connections with British Research Establishment (BRE) and recommendations about the efficacy of training programmes.
Beneficiaries
The project will be of direct benefit to:
The older people and their quality of life. The fear and actuality of falling, especially when descending steps and stairs, severely limits the mobility in the elderly and leads to social isolation and poor quality of life. Our proposal aimed at improving the safety of people on stairs, finding ways of optimising the stair-design and enhancing the competence and confidence of older users.
The National Health Service (NHS). Most accidents of older people on stairs result in fractures, which often require surgical treatment and hospitalisation. The annual cost of fracture treatment to the NHS is ~ £1 billion. Reducing the incidence of accidents by improving the locomotory performance of the elderly on stairs will reduce the cost of fracture treatment and allow redirection of scarce resources to other critical areas of NHS treatment.
The academic community and science. The project enhanced our understanding of the exact mechanisms underlying the high incidence of falls on stairs, providing knowledge on the causes of functional deterioration with ageing and the adaptability of the motor system to exercise training in old age.
Health professionals and clinicians dealing with older people, because they will be provided with specific information and advice for effective interventions aiming at improving the safety of individuals with mobility problems in old age.
Organisations and professionals concerned with stair design and building construction standard and policies, because they will be provided with specific recommendations for safer stair designs for vulnerable groups in buildings and public spaces.
To achieve the above targets, the results of the project were disseminated to the scientific community through publications in peer-review academic journals and presentations in scientific meetings.
Dissemination also involved the publication of articles in magazines and local newspapers and leaflets for the non-academic community, local community, GR surgeries and physiotherapy clinics, the University of Third Age (U3A) and relevant charitable organisations working with older people (eg, Age Concern).