Choosing a Manual Wheelchair
There are three different types of wheelchair on the market: self-propelled, electric and those that are designed to be pushed solely by someone else, i.e. attendant - propelled.
This factsheet concentrates on the last category but other types of chair are referred to so that the user can make an informed choice from the wide range of chairs available.
The first section considers the user's basic needs in relation to the features of attendant propelled wheelchairs, while the second contains specific advice on the different types of attendant-propelled chair and options that will influence the user's choice of one model as opposed to another. This is followed by notes on general 'using' issues such as maintenance. The final section deals with the various ways in which wheelchairs and their accessories can be obtained depending on the circumstances.
Just because some users have to rely on other people to move their chairs around, perhaps because they have poor grip or are unable to manage alone, it does not necessarily follow that they will use an attendant-propelled wheelchair. These chairs, with the small back wheels which are slightly lighter than most standard self- propelled chairs, may best meet the needs of 'occasional' users and those who use their chairs for short periods of time. But for those users who spend most of their time in their chairs (full time users) and who rely on someone to push them, the versatility and manoeuvrability, especially over rough ground and kerbs, of the self-propelled (large rear wheels) chairs may make them worth considering. Active user chairs, the lightest wheelchairs on the market, are increasingly being used as attendant-propelled chairs, as they have large rear wheels that can be positioned slightly further forward than those on a standard wheelchair, so that weight is redistributed and less effort is needed to push them. (For further details, see DLF factsheet Choosing an active user wheelchair).
A stable seating base
Even though these users do not need to propel the wheelchair over any great distance, a stable seating base will enable them to carry out daily living tasks as independently as possible. It is much easier to eat, use a communication aid, and transfer to and from the wheelchair from a stable symmetrical seating base than from one that does not give much support.
Some wheelchair users may never fully develop the ability to sit unaided. Others may gradually lose the ability, perhaps as the result of a progressive disabling condition. For people with mild to moderate seating difficulties, the correct size and positioning of the wheelchair seat unit components may be all that is needed to provide the user with a stable seating base. Users with severe seating disabilities may need a specialised seating system.
The following factors need to be considered:
Maximum stability will be achieved if the
user's body fits comfortably into the chair seat. If his/her weight is evenly distributed over the largest area possible, this will also provide pressure relief.
If the seat is too wide, users often sit asymmetrically in order to feel supported. If the seat is too narrow, it will be uncomfortable and increase the risk of pressure sores.
If the seat is too short, the full length of the
thighs will not be supported and too much pressure will be transferred onto the buttocks.
If the seat is too long, a pressure area may develop behind the knee, and the user may not get adequate support from the backrest.
Active user chairs are often supplied with a range of seat depth adjustments and some have frame extenders if necessary.
Shape and angle of seat
The seat needs to be level. A sagging wheelchair seat canvas will cause users to sit asymmetrically or with their thighs and knees rolled together. This may cause undue pressure and 'shearing' - the term used when the outer layer of skin is pulled in a certain direction while distorting and restricting the underlying blood vessels. This may lead to pressure sores.
When maintaining a good seating posture the angle between the thighs and the trunk is critical as it determines the stability of the pelvis. An angle of 90° is considered best for most people for daily activities. Using a contoured or ramped seat or cushion, ie very slightly lower at the back to accommodate the shape of the buttocks, is the easiest way of achieving this.
All wheelchair users should be sitting on a cushion which has been chosen at the same time as the wheelchair and fits its seat. Full-time wheelchair users will probably need a pressure relief cushion; occasional users may only need one for comfort. (For further details, see DLF factsheet 'Choosing pressure relief equipment'.)
To fully stabilise the lower body, the foot support needs to be considered next.
If an angle of 90° between the user's thighs and hips is achieved, most people will be comfortable if their knees are also at an angle of approximately 90°.
The height of the footrests on the wheelchair should be set so that they support the legs and feet and, in turn, the underside of the thighs. This will reduce further pressure on the buttocks. If the footrests are too high or the seat too low, the user's knees will be higher than the hips so that pressure under the buttocks is increased.
If the footrests are too low, or the seat too high, the user's knees will be lower than the hips and pressure will build up under the
For users with long legs, some wheelchairs have footrests that are set out at a wider angle in front, so that the leg length can be accommodated without hindering activities such as kerb climbing. Some active user wheelchairs have a choice of two or three footrests, each of which is set at different angles.
The angle of some footplates (i.e. the flat plate at the end of the footrest on which the feet are placed) can sometimes be adjusted. Feet can be very strong stimulators of muscle contractions of the whole body, may cause extension patterns, or tremor spasms in the legs. This is a common problem experienced by users with MS (multiple sclerosis). By making the footrest/footplate angle less than 90° the user's feet are prevented from slipping forwards and down off the footplates. This also stretches the calf muscles and may inhibit extension patterns and spasms.
The upper body is stabilised by the support from the backrest, which should be high enough to stabilise the upper lumbar region. Above this level, the backrest height is a matter of individual need and/or personal preference.
Some users find that if they have a stable seating base they only need a backrest that comes halfway up their back, but the disadvantage of a wheelchair with a large backrest is that the pushing handles are often too low for an attendant to push comfortably. Some active user chairs have adjustable height or tall removable push handles to overcome this problem.
Backrest shape and angle
Most users will benefit from a backrest with an appropriately shaped lumbar area. This, combined with a suitable backrest angle, should provide support and balance for the upper body.
In theory, if someone has a stable seating base, then he/she should not need armrests. Armrests should not to be used to help someone to stay in the chair - if this is the case, the user's seating base should be reassessed. A more sophisticated seating system may be necessary.
However, armrests provide useful rest and stabilising positions for users who tire rapidly and/or those who have weakness or upper limb neck muscles.
When armrests are properly adjusted they should support the user's forearms comfortably with the elbows at 90°. If they are too high, the user's shoulders will be hunched; if they are too low, the user will tend to slump to one side.
Armrests also provide users who stand up directly from their wheelchairs with an appropriate surface to push down on.. However, they do make approaching tables and work surfaces difficult and often have to be removed for transfers.
Having sorted out the seating base on the wheelchair, the next thing to consider is the type and set up of the wheelbase. For occasional and short term users, a lightweight, standard, attendant-only propelled wheelchair may be quite sufficient to meet the needs of both user and the person who is pushing. However, for full time wheelchair users, or for those people who are pushed for long periods out of doors, it may be worth considering an active user wheelchair with large rear wheels.
A chair that is easy to manoeuvre
The ability to be able to tip the front of the wheelchair so that the front castors clear the ground has an important effect on manoeuvrability. This helps the attendant to negotiate small obstacles such as an uneven surface or grids. 'Tippiness' is the term used to describe the ease with which this can be done.
The position of the wheels affects the ease with which a chair can be tipped. The wheels on standard wheelchairs tend to
be set quite far back, so that more leverage and therefore more energy, is needed to lift the castors than is the case with an active user chair on which the wheels are set further forward under the user's body. This not only affects the leverage but also the distribution of weight over the wheels which, in turn, affects the
'tippiness' of the chair. The higher the percentage of weight placed over the back wheels, the easier it is to lift the front castors off the ground. When the rear wheels of an active user wheelchair are moved forward, more weight is placed over them. Standard wheelchairs have a weight distribution of 40:60 front to back wheel ratio; active user wheelchairs have a 30:70 ratio.
This weight distribution also affects the rolling resistance, i.e. how much energy is lost during pushing. This can be calculated by dividing the weight of the wheelchair by the area of the wheel which is in contact with the ground. The area of large rear
wheels in contact with the ground is approximately twice as much area as that of small front castor wheels (e.g. 10mm:5mm).
The average active user wheelchair weighs 12kg and the weight is distributed
30:70 front to back wheel. Using the above calculation, it can be seen that it has a rolling resistance of 1.5.
If a standard, self-propelled wheelchair weighs 18kg and the weight is distributed
40:60 front to back, again using the above calculation, it can be worked out that this type of wheelchair has a rolling resistance of 2.5.
If a standard, attendant-propelled wheelchair (with small wheels and therefore small area back and front) weighs 15.5kg, the above calculation will show that it has a rolling resistance of 3.1.
The above shows that the larger the wheel, the less energy is needed to move it. Also, to achieve the minimum rolling resistance, as much weight as possible without compromising stability needs to be
placed over the larger back wheels. This is why many people prefer to use a wheelchair with large rear wheels as an 'attendant'-propelled chair. From the point of view of the person pushing, the large rear wheels are easier to manoeuvre up and down the kerbs as well as over rough and uneven ground.
An energy conserving chair
A wheelchair should be easy to move around so that an attendant has to expend as little energy as possible. This is especially important if he/she has to push the person in the wheelchair for most of the day.
The length of the wheelbase also affects how much energy is needed to manoeuvre a chair. As the wheelbase is decreased, the turning circle is also shortened, with the result that less energy is needed to turn. Active user wheelchairs have adjustable wheel axle plates which allow the rear wheels to be moved forward to decrease the wheelbase. Moving the rear wheel forward also has the effect of making the chair tip more easily, so a compromise position needs to be found.
A chair that is easy to steer
If a wheelchair's rear wheels can be cambered (i.e. angled towards the chair at the top), the effort required to propel it across a slope in a straight line will be reduced dramatically. Anyone who pushes regularly outdoors and has to tackle pavements will therefore benefit from cambered wheels.
Cambered wheels also increase the ease with which the user can turn the wheelchair. For everyday use, camber up to 5° is acceptable; beyond this the chair often becomes too wide to go through doorways and into small rooms. Wheelchairs with small rear wheels cannot be cambered.
A chair that is easy to transport
Most people using an attendant-propelled wheelchair will rely on someone else to lift and carry it around. Wheelchairs can be cumbersome and heavy to lift into a car. Chairs with a cross bracing mechanism underneath can be folded and can be made lighter by removing the legrests and armrests and quick release wheels, where possible. There are the few 'compact' chairs that fold forwards into a 'golf bag' shape. These are easier to transport since they form a compact package. (See DLF factsheet Out and about with your wheelchair).
A chair that is versatile/adaptable
The body shape of a person, size and his/her disabilities do not always remain static. As changes occur, wheelchair requirements may also change. Chairs which have interchangeable components or those which are adjustable can be altered to meet changing needs.
A chair that meets the carer's needs
If the person who is pushing the wheelchair is also the carer, it is especially important that the wheelchair meets as many of the carer's needs as possible. Reducing energy expenditure and increasing the chair's manoeuvrability and transportability will make life easier for the carer as well as helping to minimise the risk of back injury.
In addition, it should be possible for the carer to take the wheelchair user to a great many places that had previously seemed either difficult to get to, or even inaccessible.
A chair that makes the user look good and feel confident
A chair that is energy efficient and looks aesthetically pleasing will inspire confidence in the user.
ATTENDANT PROPELLED WHEELCHAIRS
WHAT FEATURES SHOULD YOU CONSIDER WHEN CHOOSING A NEW WHEELCHAIR?
Steel - strong, cheap but heavy.
Aluminium - lighter and not too expensive.
Enables wheelchair to be folded flat for easier storage and transporting.
Compact folding frame
Folds to a smaller size than the average folding frame so can be stored in small places.
Enable an attendant to assist in kerb climbing.
An attendant-propelled wheelchair may have four fixed pneumatic wheels or wheels at the back and two castors at the front.
Pneumatic wheels provide better shock absorption than static wheels. If the wheels are fixed they are more difficult to manoeuvre as the chair has to be tipped onto its back wheels, to raise the front wheels off the ground, in order to turn the chair.
Offer better shock absorption than solid ones but may puncture.
Hard-wearing but may provide a rougher ride.
Wide profile tyres tend to provide better shock absorption than narrow profile tyres
Rear wheels Pneumatic/solid
Most brakes rely on pressure against the tyre - a few press against the hub which has the advantage that the brakes work even if the tyres are quite flat. Rear operated brakes can be an option if users could harm themselves on wheel- mounted brakes - the standard brake levers are removed and replaced with attendant-operated foot or hand controls at the rear of the chair.
Can get in the way when transferring.
Reduce size and weight of the wheelchair for storage and transportation.
Can be moved out of the way for transferring.
For users who need to have their legs raised for long periods.
To stop the user's feet from sliding off the back of the footplate and getting caught in the wheels.
Allow access to work surfaces, but do not offer much arm support.
To provide maximum support.
May be more convenient for someone who needs to transfer sideways than detachable ones which can be mislaid.
Reduce size/weight of wheelchair for storage and transporting.
Backrest and seat
It is important that users are accurately assessed for the right sized seat and
correct height backrest, as these features will determine posture and comfort.
A lighter weight wheelchair is usually an advantage as it is easier for the carer to push and lift.