Mobility Info - Canada
Buying Guide For Wheelchairs
Broadly speaking, wheelchairs can be divided into three main categories: self-propelled, attendant-propelled and electric or power chairs. Self-propelled chairs are pushed by the occupant, who rotates rims on the rear wheels. These wheels tend to be large, which facilitates propulsion and kerb-climbing.
The chairs themselves are lighter and easier to transport and maintain than power chairs, but the user must have sufficient arm and upper body strength to turn the wheel rims. Nevertheless, many self-propelled chairs also have handles that allow an attendant to push them when required.
Self-propelled chairs come in standard or active user versions. The latter are very adjustable to cater for the user’s specific needs; they are useful for playing sports and should also be considered by those who spend most of their time in a wheelchair. Although this guide specifically addresses self-propelled chairs, much of the advice relates equally to the other types of wheelchair.
Considerations Before Purchase
It is a good idea for anybody getting a wheelchair for the first time to have a medical assessment beforehand from an occupational therapist or similar. The user’s age, strength, size and degree of disability will need to be taken into account, as well as any specific mobility problems. Consider when and where the chair will be used and, if possible, try out the chair in that environment before you buy.
The wheelchair’s seat should be stable and symmetrical, comfortably accommodating the user’s body with their weight distributed evenly over the widest possible area – this will aid pressure relief. If the seat is too wide, the occupant will tend to sit asymmetrically whereas a too narrow seat risks pressure sores. A seat that is too short will leave the thighs not sufficiently supported and put undue pressure on the buttocks; one that is too long will put pressure on the back of the knees and encourage a gap between the user’s back and the backrest.
If the seat is not level but sags in the middle, the thighs and knees will tend to roll together, causing “shearing”. This is where the skin is pulled in one direction, restricting the blood vessels beneath and leading to pressure sores. The angle between the thighs and torso should ideally be 90 degrees.
A cushion, if used, should be chosen at the same time as the wheelchair. A contoured seat or cushion that is lower at the back may help the occupant to maintain the ideal angle between torso and thighs. People who need to sit all the time will benefit from a pressure relief cushion; others may opt for one to improve comfort.
Footrests, supporting the legs and feet, should ideally keep the knees at a 90 degree angle. Too high, and they will put pressure under the buttocks; too low, and pressure will be felt under the thighs. Footrests can be set at a wider angle for those with longer legs so that they do not impede the user when climbing kerbs, for instance. The angle of the footplates on which the feet rest can usually be adjusted to prevent the feet from slipping forwards or inwards and thus stretching the muscles unnecessarily. Foot straps can also help in this regard.
The wheelchair’s backrest should be high enough to provide upper lumbar support; higher backrests are a matter of individual need or personal preference. If the configuration of the seat is stable and well adjusted, the backrest need not be overly large, although pushing handles, if used, might be low down on a low backrest.
Armrests are not essential on a self-propelled wheelchair; indeed, some users will find them more of a hindrance. However, they can provide useful rest and stabilisation for the arms, as long as they support the elbows at a 90 degree angle. If they are set too low, the occupant might lean to one side; too high, and the shoulders will be hunched. Armrests can be useful for people who stand up from their chair, though they may also hinder access to tables and work surfaces.
The size and positioning of the wheels are important considerations, since these factors affect the weight distribution and the chair’s rolling resistance, having a significant bearing on the manoeuvrability and the effort needed to propel the chair. Indeed, the ability of the user to tip the chair backwards – in order to negotiate kerbs and other obstacles – is governed primarily by the position of the wheels. The further forward they are set, the greater is the percentage of weight placed over them and the easier it is for the occupant to carry out this manoeuvre. Furthermore, the most energy-efficient means of propulsion is achieved when the rear wheel axles are set directly below the user’s shoulders.
Most standard self-propelled wheelchairs have 20 to 22 inch rear wheels, though some can be as much as 26 inches. Larger wheels mean reduced rolling resistance, making the chair easier to propel. A shorter wheelbase decreases the turning circle, so less energy is expended in turning.
Another factor that makes turning easier and reduces the effort needed to propel the chair, especially on slopes, is the camber of the wheels. This is when the rear wheels are not perpendicular to the ground but lean in at an angle of up to 5 degrees. This feature is particularly prevalent on chairs used for sports. The only possible drawback to a chair with a wide camber on the wheels is that the increased width makes it less likely to fit through narrow doorways.
Depending on when and where the chair will be used, ease of transportation might well be a key consideration, as some can be cumbersome and heavy to lift. To make transportation simpler, some wheelchairs fold using an X frame mechanism. Others have detachable parts such as footrests, armrests and even wheels. In certain models, the backrest can be folded down to reduce the height.
If the wheelchair user’s level of disability or size are likely to alter over time, it might be prudent to procure a chair that is adaptable, with interchangeable component parts. In this regard, an active user chair is more likely to fit the bill than a standard self-propelled chair.
inally, any carer’s needs should not be overlooked. While the whole point of a self-propelled chair is that the user propels it, there may be occasions when a helper needs to push or has to load the chair into a vehicle. If a chair is efficient to push, manoeuvrable and transportable, it will be easier for both user and helper.
Wheelchair Components And Features
The wheelchair’s frame will usually be made of steel or aluminium. Steel is strong and inexpensive but aluminium is lighter. A rigid frame makes the chair lighter and stronger than one with a folding frame, though the latter will be easier to transport. Tipping levers on the frame can assist a helper when climbing kerbs, whereas anti-tip levers prevent the user from tipping back too far.
Pneumatic tyres offer good shock absorption and a more comfortable ride than solid tyres, as long as they are kept well inflated. Solid tyres are more hard-wearing and do not carry the risk of puncture that the pneumatic kind do.
Footrests can either be fixed – which can get in the way when transferring – or they can be detachable or swing-away to simplify this procedure. Elevating footrests are used for raising the leg(s) or for keeping them straight, such as when a leg is in plaster. Similarly, armrests are often detachable; the benefit of those that merely fold up or down or swing away is that they cannot be misplaced. Desk-style armrests allow access to a work surface. The angle and height of the backrest affect the occupant’s posture, so an adjustable backrest can be useful.
Some self-propelled wheelchairs come with pushing handles already fitted; others have them as an optional extra. As with the backrest, those whose height can be adjusted are most convenient
Beyond the basic self-propelled chair is a wide range of chairs with special features. Comfort wheelchairs are chairs that have extra improvements for comfort and support, such as contoured seats or a reclining backrest. A semi or fully reclining backrest is of benefit for those with a weak or stiff back who need to change position frequently, or for those whose treatment demands a recumbent position. This will obviously take up more space and make propulsion less manageable.
One-arm drive wheelchairs are for people who have the use of one arm only, or strength in only one side. In these chairs, the axles are linked and attached to a double hand rim on the favoured side. To move forwards, both hand rims are turned together; use of either one independently will turn the chair. It is worth noting that strength and coordination are required to operate such chairs, and that it is extremely difficult to propel them up slopes and hills.
Low-seat wheelchairs are propelled and steered using one or both feet. A footrest can be fitted for the weaker leg if only one leg is used. As this type of chair does not encourage good seating posture, it is not ideal for prolonged use. An alternative for indoor use is a castor chair, which is smaller and lighter than a standard wheelchair.
Lever-propelled chairs are operated by a push/pull action on one or two levers located beside the seat, rather than by turning the wheel rims. As with one-arm drive wheelchairs, this demands strength and coordination.
On chairs with a tilt-in-space unit, the seat and backrest tilt backwards while maintaining the angle between them. A stand-up mechanism enables the seat and backrest to flatten out, lifting the user to a vertical position. Because the occupant can reach things high up and can interact with other people on their level, it is good for them psychologically; physically it is beneficial too, as it improves digestion and blood circulation and gives pressure relief. Stand-up mechanisms are not suitable for everyone however; people with weak legs may struggle to support their own weight comfortably, and those who rarely stand may feel faint on doing so.
An elevating seat is a compromise that would allow the user to reach a higher level without standing upright. This consists of a unit, powered electrically or mechanically, that can replace the existing seat. Made to measure chairs can be customized to suit the individual, but will cost more than standard wheelchairs.
Active User Wheelchairs
These are more versatile than standard self-propelled chairs as they have flexible and adjustable components that can be tailored to the user’s specific needs. For people who spend most of their day in a wheelchair, an active user chair maximizes mobility and offers more independence. While they are ideal for the young and sporty, older users can derive just as much benefit from them.
Active user wheelchairs are lighter than standard chairs, typically weighing around 12kg. Some have titanium or carbon fibre frames, which are strong and light and will not rust. The rear wheels can be brought forwards to alter the weight distribution, making the chair easier to propel and manoeuvre. A multi-adjustable axle plate, found on many of these chairs, enables the wheels to be set at different positions – higher, lower, further forward or back. In addition, many chairs incorporate quick-release wheels.
Options available with active user chairs include a variety of frame sizes and a range of seat depths. The tension of the seat canvas can even be adjusted on some models. Backrest angle plates allow the backrest to be angled forwards by a few degrees to help maintain good posture. Sometimes a choice of footrests set at different angles can be fitted, as well as a variety of braking solutions.
Chairs used specifically for sports often have additional features. They almost always have a rigid frame and the camber of the wheels can exceed the usual 5 degrees maximum found on other chairs. This wide camber makes the chairs very quick and easy to turn. Wheels are often of a composite type, with around six large spokes that are simple to clean and give a sporty appearance. Sports tyres have hardly any tread so that they meet with less resistance. However, this also means they can wear out quickly. The front castors tend to be small and solid but are not suitable for outside use.
Active user chairs can double as good attendant-propelled chairs, because the same features that make them easy for the occupant to operate also make them easy for a helper to push.
