Wheelchairs

views updated Jun 11 2018

WHEELCHAIRS

The wheelchair is made from many components ideally chosen to meet the needs of the person using the chair. The reasons to choose a wheelchair and the options available are as varied at the people who will use them. The most important thing before purchasing or renting a wheelchair is to make sure it will best fit the needs of the individual who will be using it. The best way to do this is to work with a wheelchair specialist (e.g., occupational therapist or physician) who can advise on many issues.

Cost

One point to remember is that the most economical chair is not always the cheapest chair. An inexpensive chair can be costly not only in the monetary sense (i.e., repairs and replacement), but to the individuals health, comfort, and safety. Getting advice from and experienced practitioner will allow you to choose the most appropriate and economical chair for yourself or your loved one.

Frames

Frames can be solid or folding. Folding frames make for easy transport and storage. The folding mechanism is flexible and gives the chair a smooth ride when negotiating uneven surfaces by allowing all four wheels to stay in contact with the ground more of the time. Rigid frames are strong and light. They usually require little maintenance, which can reduce long-term costs. They have a more responsive feel and allow for more precise alignment of the wheels. This latter feature is often desirable to the young or very active user. When choosing a frame it is important to consider the vehicle that will be used to transport the chair and where the chair will be kept (i.e., in the trunk versus the back seat). How the components break down or fold for transport will be important.

Seats

The seat supports the upper legs and the buttock region. The seat base can be of a sling or rigid type. The hammock or sling type base (Fig. 2) is the least expensive and folds easily with the chair. This is appropriate if a person is only using the chair on an occasional basis. If an individual is spending a great proportion of the day in a wheelchair a firmer base is needed. On the seat base a cushion will be placed. Every wheelchair should be fitted with a removable cushion for pressure distribution, shock absorption, and positioning. The types of cushions are innumerable but are most often foam, gel, air, or combination cushions. A proper cushion helps to decrease pressure by distributing it over as great an area of the persons legs and gluteal region as possible. For example, if the seat depth is too short it will decrease the weight that can be carried under the thighs and could cause dangerous increases in pressure in the gluteal areas leading to skin breakdown. It is generally recommended that users have one to two inches of space between the cushion edge and the back of the knees. On the other hand, if a cushion is too long it can create pressure behind the knees and interfere with the legs when used to assist in propelling the wheelchair. Sometimes cutouts or contours are made to the cushion so that a person can use the legs to assist in propelling.

The seat height can be lowered for people who can use their feet to move their wheelchair. Foam cushions can be contoured. For example, in a person with thigh spasms, a central hump or pummel can help keep the legs properly positioned. People with poor sensation are at even higher risk for pressure damage to the skin. Air or gel cushions may be recommended in such people to further reduce pressure. The cushion cover is important too. It should be removable for laundering, and if incontinence is a problem waterproof or water-resistant covers may be desirable. The dimensions of the compressed cushion will affect many of the wheelchair dimensions, such as backrest and arm rest heights, and thus the decision on the type of cushion should be made early.

Backrest

The backrest supports the spine and can extend to include support of the head if needed. The height will depend on the persons needs, but a proper back should support normal posture, prevent pain and fatigue, and allow maximal mobility. The hammock or sling back, like the sling seat, folds easily with the chair but does not provide a great deal of back support. More rigid backs provide increased support and there is a wide range of shapes and styles depending on what is needed. Those who are able to propel their own chairs using their arms benefit most from a backrest that ideally should not extend higher than about two inches below the lower angle of the shoulder blade. This allows easy propulsion and avoids rubbing or irritation of the arms during wheeling. A higher back rest may be needed for proper support by someone who does not propel themselves, has weaker trunk support, or uses a power wheelchair negating the need to propel themselves. A high backrest or headrest may be needed if a tilting or reclining feature is being used on the chair. These features are often used in the more physically impaired person for repositioning and pressure relief to protect the skin.

Push handles can be part of the frame or the back rest and are generally added if the individual will need someone to assist them in propelling the chair all or part of the time.

Arm rests

The armrests support the arms and shoulders in comfortable positions and are often used to push off of for transferring from sitting to standing or held on to for balance. Desk-length armrests are shorter than standard length rests and are often chosen so that a person can pull up to a desk or table for easier access. The shorter length of these armrests is undesirable if the wheelchair user needs to use them to assist pushing into a standing position. In this case a full-length armrest would be preferred. Greater support may be needed if an arm is significantly impaired, as in the case of a person with an arm paralyzed from stroke or a person with a high-level spinal cord injury. The armrests in this situation may be padded and may be a trough-like configuration to assure proper support and protection of the limb. Armrests should always be removable to assist in sideways transfers. Wrap around armrests attach to the back of the frame instead of the side and can be used to help keep the width of the chair to a minimum. This can be helpful for easier mobility through doorways or other tight spaces.

Clothing guards

Clothing guards protect clothing from the wheels. They are optional and can be part of the armrest itself or a separate removable part.

Footrests

The footrest and legrest support protect the lower leg and feet. If they are too high they decrease the weight carried through the back of the thighs and can cause increased pressure over the buttock region. If they are two low they can cause pressure over the posterior thighs and cause problems with clearing barriers in the environment such as incline transitions. The suggested height of the footrest from the floor is two inches. Removable footrests are helpful for transferring users in and out of the chair. One may wish to remove one or both of the footrests at different times. A good example for such a need is when assisting a person who has had a stroke. They may want to leave a footrest on to support a weak or paralyzed leg and keep the other footrest off so that the strong leg can assist in propelling the chair. A person with an amputation or a person who chooses to use both feet to propel a chair may also wish to remove the footrests. It is important to remember in these situations that the footrest does help provide balance to the wheel chair and can act as a safety guard against forward tipping. Elevating footrests can be useful for controlling swelling or to temporarily support an injured limb. With the footrest in this position the chair becomes longer and therefore can be harder to maneuver. The elevated footrest can also create balance problems and an increased risk of tipping accidents and therefore should be used with caution.

Wheels

In the manual chair the usual size of the rear wheel ranges from twenty to twenty-six inches in diameter. A larger wheel increases the height of the seat off the ground and decreases the rolling resistance, thus easing the effort of pushing. The rear wheels can be solid or pneumatic. Solid wheels have a low rolling resistance and are very easy to maintain. They are ideal for use in institutional settings or for indoor use in noncarpeted areas. Pneumatic wheels have better grip on carpeted surfaces and are better if there is going to be significant outdoor use, but they run the risk of flats and require higher maintenance. The flat tire problem can be circumvented by the use of a foam insert that can prevent leaks. Wire spokes are lighter in weight but higher in maintenance. Most older persons will select large plastic spokes referred to as mag wheels. The wheels can be offset posteriorly to decrease the risk of tipping backwards.

Hand rims are used to propel the chair. The materials used in hand rims vary from steel to aluminum, and the rims are often coated with rubber or plastic materials to assist grip and protect hands. Modifications to hand rims such as lugs (knobs) can be added to assist the person with a weak grip in pushing the wheelchair. Most wheelchairs are meant to be propelled with two hands, however, one-arm drive mechanisms are available. The front wheels are called the casters. These are usually eight inches in diameter, but like the rear wheels vary in size. These allow turning of the wheelchair. One needs to assure that the casters and footrests are properly positioned so as not to interfere with each other.

Safety

Safety is a paramount concern. This starts with assuring that a wheelchair user works with the proper individuals, not only in purchasing a chair, but also in assuring that the caregivers and/or the wheelchair user knows how to operate the chair properly. There are 51.3 wheelchair deaths and 36,559 nonfatal wheelchair accidents per year reported in Umat and Kirbys 1995 article on wheelchair related injuries. Being safe in the chair includes having a chair that fits the user properly to avoid pressure and other injuries. It also includes knowing how to transfer, reach, balance, and propel safely so that the wheelchair becomes an aid to independence and not a threat to health and well-being. The best way to assure safety and prevent injury is to make sure a trained individual teaches the wheelchair user and any involved caregivers how to properly and safely use the wheelchair.

Safety components may include brakes, anti-tippers, grade aids, and belts.

There are numerous brake systems available. The most common form is the push handle style (Fig. 2); the lever on this style can be lengthened to assist someone who is weak or who does not have the strength or reach to apply the conventional style. It is essential that the caregiver and wheelchair user are able to apply and disengage them properly.

Anti-tippers are another safety feature. These prevent backward tips in situations such as when wheeling up a grade. As mentioned earlier the footrest can act as a forward anti-tipper. Grade aids decrease the work of propelling up hill. They also prevent the individual from rolling backwards in such a situation. Belts at the chest or waist level can help a person to safely maintain position in their chair. However, at the same time a user must be careful because they decrease the ability to shift position and if not placed or applied properly can run the risk of slipping or choking. In addition to the components, safe use of a wheelchair lies in the proper set up of a chair for a person to maximize balance and minimize tipping.

Power mobility

When an individual is not physically capable of propelling a manual chair or if endurance is a problem, then power mobility is an option. The individual can use power mobility, if they have the cognitive ability and some form of motor controlwhether through head, hand, or mouththat can be used to operate the chair. If the individual does not have the cognition to operate a power chair independently, power mechanisms can be used to assist the caregiver in pushing or positioning the individual. Power chairs can be an expensive option and a user or caregiver should avoid entering a purchase agreement without consultation with a wheelchair specialist.

Wheelchairs have become an increasingly important intervention in the older adult. The options are endless and when combined properly can help maximize a persons independence, health, and well-being.

Christine Short

See also Arthritis; Home Adaptation and Equipment; Rehabilitation; Walking Aids.

BIBLIOGRAPHY

Buschbacher, R.; Adkins, J.; Lay, B.; and Braddom, R. Prescription of Wheelchairs and Seating Systems. In Physical Medicine and Rehabilitation. Edited by Randall L. Braddom and W. B. Saunders Co., 1996. Pages 381400.

Currie, D. M.; Hardwick, K.; and Merburger, R. Wheelchair Prescription and Adaptive Seating. In Rehabilitation Medicine: Principles and Practice, 3d ed. Edited by Joel A. DeLisa and Bruce M. Gans. Philadelphia: Lippincott-Raven Publishers, 1998. Pages 763788.

Kirby, R. L. Principles of Wheelchair Design and Prescription. In Neurologic Rehabilitation. Edited by Richard B. Lazar. New York: McGraw-Hill Health Professions Division, 1998. Pages 465481.

Kirby, R. L. Manual Wheelchairs. In PM and R Secrets. Edited by Mark A. Young and Steven A. Steins. Philadelphia: Hanley and Belfus, Inc., 1996. Pages 117120.

Ummat, S., and Kirby, R. L. Nonfatal Wheelchair-related Accidents Reported to the National Electronic Injury Surveillance System. American Journal of Physical Medicine and Rehabilitation 73, no. 3 (1994): 163167.

wheelchair

views updated May 17 2018

wheel·chair / ˈ(h)wēlˌche(ə)r/ • n. a chair built on wheels for an invalid or disabled person, pushed by another person or propelled by the occupant, or motorized.