Michael L. Boninger

Laura McClure

Rory A. Cooper

Mark Schmeler

Rosemarie Cooper

Freedom of movement is an essential component of human independence. In the Institute of Medicine model on the enablement/disablement process (1), a wheelchair and its components are fundamental for altering the interaction a person with a mobility limitation has with the environment. Not surprisingly, studies in various populations and cultures have repeatedly shown that mobility is closely tied to quality of life (2, 3, 4, 5, 6). It is therefore critical that the physiatrist takes an active role in the wheelchair prescription process. Fundamental to this role is knowledge related to the understanding of the complex components that make up seating and wheelchairs.

Seating and wheelchair technology has become increasingly complex. In this chapter, the readers will find information to help them gain an understanding for differentiation among various types of manual and power wheelchairs, and seating systems. In addition, newer hybrid wheelchairs, such as power add-on units, are discussed. The importance of the wheelchair-user interface, ride comfort, durability, selection of accessories, and powered-wheelchair control devices is also stressed. The readers are introduced to wheelchair and seating measurements and a variety of cushions and postural supports.


Team Approach

The complexity of wheelchair and seating components combined with the nuances of individuals and various disease processes make it virtually impossible for a single clinician to act independently when prescribing assistive technology for mobility. For this reason, it is important to involve an interdis-ciplinary team in the decision-making process (7). The most important team member is the patient. The opinions and desires of the patient are critical to a successful fitting but must be assessed in terms of their level of knowledge and insight. Some patients have been using a wheelchair for years and know exactly what they are looking for. For these individuals, team members act to provide unbiased information. Alternatively, a novice patient may have little knowledge of what is available and the trade-offs of each decision. For this individual, the team will need to be more directive. The family and caregiver should also provide input, as they will be the next most affected by the choice of wheelchair.

The assessment team can consist of a variety of rehabilitation professionals (Table 78-1). Currently, Medicare and the majority of private insurance companies require a face-to-face physician assessment focused on mobility before providing a wheelchair. Given the training on function and mobility, a physiatrist can be the most appropriate physician to complete this assessment. Often an occupational or physical therapist working with the physician will conduct an evaluation. Ideally, the therapist will be certified by The Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) as an assistive technology practitioner (ATP). Other professionals who can be certified and may be part of the team include a rehabilitation engineer, an Assistive Technology Supplier (ATS), or Certified Rehabilitation Technology Supplier (CRTS, National Association of Rehabilitation Technology Suppliers).

Those involved in the wheelchair selection process should have knowledge about the technology available on the market. Magazine articles and commercial database sources such as ABLEDATA (http://www.abledata.com/) and SpinLife (www.spinlife.com) are good places to research devices or to direct patients who want to educate themselves. (As with any medical advice, patients should be cautioned that information gathered from TV, internet, magazines, etc., should be confirmed with their physician, therapist, or technology supplier.) People choose their seating and mobility devices based on the features available that will facilitate activities or address needs (8); therefore, it is important to be aware of the user’s preferences and the features of various devices.

Patient History

The interview process is largely the same as any standard history conducted with a patient. The necessary information such as age, past medical history, and current medical diagnosis needs to be gathered. The assessment process involves obtaining critical information about the user and his or her environment, family support, and past use of assistive technology. It is essential to determine if the individual’s physical impairment is changing rapidly or is stable. It is important to establish the diagnosis that requires the wheelchair and to assure that there are no ongoing medical problems or complications that can affect the wheelchair prescription and the patient’s health.

To properly specify a wheelchair, it is important to understand both the intentions and the abilities of the user (9). It is essential that the clinician takes into account the characteristics
of the intended user and potential caregivers to ensure that the wheelchair will be accepted and used by the user. Access to a range of heights might be important to reach objects in the home and other environments. To support vocational needs, specific requirements may exist for mobility within a laboratory, operating room, courtroom, or machine shop. Leisure activities, pursued in such places as community centers, restaurants, movie theaters, and recreational environments, often place the most demands on the wheelchair. For some users, many of the desired tasks may be accomplished simply and with existing off-the-shelf technology. Others will require custom products, and some will not be able to achieve all of their goals with existing technology.

TABLE 78.1 Members of the Seating and Assessment Team


Rehabilitation engineer

Occupational therapist

Physical therapist

Rehabilitation technology supplier

Speech and language pathologist

Rehabilitation physician

Additional necessary information includes type of insurance, physical capabilities and if the individual is able to transport a wheelchair. Also, if the patient has been using a chair, historical information about his or her current chair should be addressed, including problems he or she may be having. The wheelchair model chosen should also be compatible with the user’s public and private transportation needs (such as a bus, train, car, van, or airplane) and home/Activities of Daily Living (ADL) environment.

The surface conditions may impose restrictions on the type of wheelchair that is most appropriate. The regularity of the surface and its firmness and stability are important in determining the tire size, drive wheel location, and wheel diameter. The performance of the wheelchair is often dictated by the need to negotiate grades, as well as height transitions, such as thresholds and curbs. The clearance widths in the environment will determine the overall dimensions of the wheelchair. A scooter may not fit around a corner in an average person’s home but might perform well outdoors on a sidewalk. The need to be able to operate in snow, rain, and other weather conditions are important considerations as well.

Physical Examination

With an understanding of the individual’s need or desire to perform different activities, the next step is examining the user. The history likely provided significant insight related to his or her physical abilities. To verify this, a physical examination should focus on aspects of the patient that will help (a) justify the wheelchair and seating system, (b) determine the most appropriate wheelchair and seating system, and (c) assure that medical issues are appropriately addressed. Based on the interview of the patient, it may be possible to omit some portions of the examination listed below.

Often individuals require a wheelchair because of cardiopulmonary disease. For these individuals it is important to document a heart and lung examination. Attention should be paid to dyspnea on exertion and changes in vital signs with activity. These findings can be used to justify a power wheelchair, as the energy cost of wheelchair propulsion is not less than walking (10). Other common reasons for requiring a wheelchair are musculoskeletal and neurologic deficits. The clinician should document the neurologic and musculoskeletal deficits in a methodical fashion. In a patient with a stroke, for example, an examination to check for neglect or visual field deficit is important because it will impact on the ability to independently drive a chair.

Obvious examination items include strength and range of motion. For individuals with chronic arthritis problems, the examination should document the painful, swollen, or malaligned joints. When no strength deficit is seen, it is important to document issues with coordination, tone, and proprioception. For example, a study by Fay et al. found that many individuals with multiple sclerosis were unable to effectively propel manual wheelchairs due to increased tone and decreased coordination (11). Participants showed an inability to maintain a speed comparable to community walking speed (1 m/s). This type of finding can provide justification for the device selected.

While completing the examination, the physician should be thinking about how the individual will control the wheelchair. If there is poor hand coordination, head control or switch control may be needed. In certain cases, a foot joystick may be possible.

For some individuals, the examination and history will not necessarily establish a clear need for a wheelchair. In these cases, it is important to consider alternative options that meet the individual’s functional needs.

It is important to establish how long the individual will be using the chair. If from the history and examination it is determined that the deficit will be transient, then a rental chair may be appropriate. Medicare will rent chairs for their beneficiaries. This is a good option if the duration of use will be short and the device does not need to be customized. If during the history and physical examination medical issues that require intervention are identified, it may be appropriate to delay wheelchair prescription so that changes in the patient status do not necessitate changes in the prescription. In such case a rental may provide short-term mobility.

Stability can be assessed by observing the individual in the current wheelchair or by asking him or her to sit unsupported on a mat table. Ask the patient to perform simple reaching tasks to determine the lateral and forward stability of the trunk, hand and arm strength, and hand fine motor skills. The presence of kyphosis, scoliosis, or other fixed deformities should be determined. Critical point to evaluate is hip and knee range of motion because contractures may need to be accommodated. Poor stability usually indicates the need for special attention to seating and position. Appropriate seating can enhance reach and stability, thus improving the performance of manual activities from the wheelchair. It is well known that various groups of wheelchair users, such as individuals with tetraplegia and cerebral palsy, will develop kyphosis or scoliosis over time (12).
What is less well known is whether spinal deformities can be prevented with appropriate seating. Even if prevention is not a goal, accommodation is needed for comfortable seating.

TABLE 78.2 Medicare Recommended Documentation Items


Related diagnoses


How long the condition has been present

Clinical progression

Interventions that have been tried and the results.

Past use of walker, manual wheelchair, scooter, or power wheelchair and the results

Physical exam


Impairment of strength, range of motion, sensation, or coordination of arms and legs

Presence of abnormal tone or deformity of arms, legs, or trunk

Neck, trunk, and pelvic posture and flexibility

Sitting and standing balance

Functional assessment

Any problems with performing activities including the need to use a cane, walker, or the assistance of another person

Transferring between a bed, chair, and wheelchair

Walking around their home—to bathroom, kitchen, living room, etc.—provide information on distance walked, speed, and balance

Finally, a thorough check of the individual’s skin is important. This may not be needed for individuals with cardiopulmonary disease, but it is essential for individuals with neurologic deficits or those with previous history of pressure sores. The examination should include not only the buttocks but also the feet and calves, which can be affected by pressure against a leg rest. Attention should be paid to bony prominences and previous scars. This examination will help with cushion selection and wheelchair setup. Large, previously untreated ulcers are sometimes discovered, ultimately leading to treatment before seating plans can be implemented.

For many people a few simple measurements can be used to determine the proper dimensions for a wheelchair (13). Body measurements are typically made with the consumer in the seated position. Probably the most obvious body measurements are the consumer’s height and weight. The consumer’s weight is critical to obtaining a wheelchair that is sufficiently strong as many wheelchairs are only rated to hold up to 113 kg (250 lb). The height of the wheelchair user provides information about the person’s size and can be used to check the final wheelchair measurements. For example, the sum of the sitting height, sitting depth, and lower-leg length should be close to the person’s supine height. Additional measurements and definitions are used when specialized seating and postural support systems are required. These measurements may be completed by any one of the team members.


Providing appropriate and quality wheelchairs requires well organized and often extensive documentation. At the very least, a prescription and various insurance forms must be provided. For more expensive and complex interventions, a letter of medical necessity (LMN) is required. Table 78-2 list Medicare recommended assessment findings for power wheelchair provision. This letter can consist of two components: a cover letter and the “client/patient evaluation and intake form.” The cover letter summarizes the person’s disability, problems with existing equipment or method of mobility, evaluation procedures, conclusions, explanation of why lower-cost alternatives will not work, risks of not providing the equipment, and a line-item justification for each of the various components being recommended. The “client/patient evaluation and intake form” guides the evaluation process and captures in-depth information of the evaluation findings required to support recommendations of the appropriate seating and mobility interventions. Often, a part of this exam will be completed by an occupational or physical therapist. The therapist will perform clinical trials and simulations, which allow the patient to try many different devices.

The prescription process should include a home assessment to make sure the device selected will work in the home environment. A home assessment conducted by the supplier is required by Medicare. This requirement highlights the importance of working with qualified suppliers such as those with the ATS credentials. If a home visit is conducted, documentation of the visit should be included in the LMN.

In order for any health insurance provider to approve coverage for a wheelchair and seating system, the practitioner must establish and document medical necessity. Each funding source may have its own definition of “medically necessary,” however; in general, when it comes to wheelchairs, it is necessary to accommodate or replace a malfunctioning body part (i.e., paralysis or weakness of the lower extremities) or to reduce or manage disability. Many funding sources also require
the recommended intervention to be the least costly, reasonable alternative. Therefore, as part of an evaluation, it is helpful to document that lower-cost alternatives have been tried and were unsuccessful, and to cite specific reasons for the higher-cost choice. It is also helpful to document the potential outcomes if the person is not provided with the equipment. Examples of these risks include falls and fractures, development of pressure sores, joint contractures and musculoskeletal deformities, increased pain and discomfort, loss of function, and ultimately being more restricted to a bed or chair.

The final letter is reviewed by both the therapist and physician and cosigned. It is not appropriate for a physician or a therapist to sign the LMN for a client/patient if he or she has not evaluated the person for the device prescribed.


It is important that the delivery and the final fitting of the device is documented and verified by a follow-up visit with the team or one of the team members. This visit provides the client with the support of the team to be comfortable with the final acceptance and approval of the device and supports the supplier with appropriate clinical delivery documentation. Finally, this visit can be used to refine the patient’s wheelchair driving skills to enable safe operation.


Manual wheelchairs offer many advantages over powered mobility. Manual wheelchairs are much easier to transport because of their lighter weight. No special equipment is needed to place a manual wheelchair in a backseat, and individuals with paraplegia and tetraplegia are often capable of transporting their wheelchairs independently without additional technology. In addition, manual wheelchairs generally require less maintenance than power devices, and there are no concerns related to batteries or controllers. Finally, manual wheelchairs offer a degree of physical exercise that can benefit the wheelchair user.

Depot and Attendant-Propelled Wheelchairs

The depot or institutional wheelchair is essentially the same wheelchair that was produced in the 1940s. This type of chair corresponds to the Medicare category of K0001 and, despite its numerous shortcomings, is the default chair for many insurance companies and Medicare. Today’s depot wheelchairs may be a bit lighter than the 1940s models, but the basic frame design is unchanged. Depot wheelchairs are intended for institutional use, where many people may use the same wheelchair. These wheelchairs are typically used in airports, hospitals, and nursing care facilities. They are inappropriate for active people who use wheelchairs for personal mobility, including older persons in nursing homes. Depot wheelchairs are designed to be inexpensive, to accommodate large variations in body size, to be low maintenance, and to be attendant propelled. Unlike the attendant-propelled chairs described below, depot chairs are designed neither for the comfort of the person being transported nor for the person pushing the chair. A typical depot wheelchair will have swing-away footrests, often removable armrests, a single cross-brace frame, and solid tires (Fig. 78-1). Depot wheelchairs have sling seats and back supports, which are uncomfortable and provide little support. Swing-away footrests add weight to the wheelchair; however, they make transferring into and out of the wheelchair easier. Armrests provide some comfort and stability to the depot wheelchair user and can aid in keeping clothing off the wheels. Depot chairs typically fold to reduce the area for storage and transportation. Solid tires are commonly used to reduce maintenance. Solid tires typically dramatically reduce ride comfort, increase rolling resistance, and add weight. There is very little, if anything, that can be adjusted to fit the user on a depot chair. Typically, only the leg-rest length is adjustable. Depot chairs are available in various seat widths, seat depths, and backrest heights.

FIGURE 78-1. K0001 depot-style wheelchair.

Attendant-Propelled Chairs

Not all wheelchairs are propelled by the person sitting in the wheelchair. In many hospitals and long-term care facilities, wheelchairs are expected to be propelled by attendants. In addition, some individuals with severe disabilities are unable to propel a wheelchair or control a power wheelchair. For children who use attendant-propelled chairs, it is necessary to continually reassess if they may be able to use independent mobility. The primary consideration in the attendant-propelled chair is that the wheelchair has two users: the rider and the attendant. If the wheelchair is propelled solely by attendants with no assistance from the rider, then there may be no need for the larger drive wheels (Fig. 78-2). To keep the attendant comfortable, the weight of the chair should be kept as light as possible and the push handles adjusted to the height of the attendant. If the occupant will be sitting in the chair for prolonged periods of time, then attention must be paid to comfort. For this reason, attendant-propelled chairs often have tilt-in-space as an option.

FIGURE 78-2. Attendant-propelled wheelchair with tilt-in-space.

A variant of the attendant-propelled wheelchair is sometimes called a “Gerry” chair in reference to geriatric users. This type of attendant-propelled wheelchair is typically designed to make transfer out of the chair difficult. The rider is seated in a large recliner-type wheelchair. The soft padding, reclined position, small wheels, and large size make it impossible for the rider to move the wheelchair and difficult for most riders to exit the wheelchair. This helps long-term care facility to exercise control over their clients with cognitive dysfunction. There has been considerable discussion about the appropriate use of attendant-propelled chairs that significantly restrain the rider’s independence.

Lightweight and Ultralight Wheelchairs

The terms lightweight and ultralight wheelchairs are derived from the Medicare categories K0004 and K0005, respectively. K0004 wheelchairs must weigh less than 34 lb without footrests or armrests, and K0005 must weigh less than 30 lb without foot or arm supports. K0004 wheelchairs have very limited adjustability (Fig. 78-3). Like depot chairs, they can be sized to the user, but many of these chairs do not offer features such as adjustable axle plates, quick-release wheels, or a method to change the seat to back angle of the wheelchair. Because of the way Medicare reimbursement works, manufacturers attempt to build the best wheelchair possible under a certain Medicare reimbursable cost. Unfortunately, this practice of cost engineering does not necessarily lead to improvements in design. In addition, this Medicare policy may cause dealers to push wheelchair users toward K0001 and K0004 chairs which have higher profit margins.

The ultralight wheelchair is the highest-quality chair that is designed specifically as an active mobility device (Fig. 78-4). These chairs, which can easily cost more than $2,000, are usually highly adjustable and incorporate numerous design features made to enhance the ease of propulsion and increase the comfort of the wheelchair user. When made of titanium or high strength aluminum, this chair can easily weight less than 20 lb. At present, it is necessary to justify the need for a K0004 or K0005 wheelchair instead of a standard K0001. Unfortunately, the process of getting prior authorization—meaning the vendor is guaranteed ahead of time to be reimbursed for the wheelchair—is cumbersome. As a result; vendors are unwilling to take the risk that a $2,000 item will be rejected by Medicare and become their problem. Currently, Medicare allows vendors to ask for preauthorization of these chairs; however, few vendors take advantage of this opportunity.

FIGURE 78-3. K0004 lightweight wheelchair with folding cross-brace design.

FIGURE 78-4. K0005 ultralightweight wheelchair with cantilever design.

Ultralight wheelchairs usually have a number of options and adjustments that can be made to appropriately fit the user. Following is list of many of the components of chairs and options that are available. It is important to remember that every component adds weight to the chair. A balance must be reached between providing the optimal equipment to make the individual as functional as possible and to keep the chair as light as possible. Some of these options are also available on lightweight and depot type chairs; however, the components used on ultralight chairs are generally lighter and better in quality.


There are two basic frame types: folding and rigid. Within these two frame types, there are a number of different varieties. The most common type of manual wheelchair frame is the folding cross-brace frame (see Fig. 78-3). When viewed from the back of the frame, the cross members form an X with a hinge located in the middle of the X. The chair is folded by pulling upward on the seat upholstery. Cross-member folding mechanisms are simple and easy to use. However, the wheelchair may collapse when tilted sideways, and the frame becomes taller when folded. Some chairs incorporate snaps or over-center locking mechanisms to reduce the problem of frame folding while on a side slope.

The most common rigid chair is the box frame. The box frame is named for its rectangular shape and the frame tubes that form a “box” (9). Box frames can be very strong and very durable. These frames can also be collapsed to relatively small dimensions. The backrest usually folds forward, and when used with quick-release wheels, the chair becomes a rather compact shape. An alternative to the box frame is a cantilever frame that can act a suspension element (i.e., there is some flexibility purposely built into the frame). These cantilever frames may also have fewer tubes and fewer parts and thus be more aesthetically pleasing (see Fig. 78-4).

Some manufacturers offer suspension elements on the frame. This is in part a response to evidence that vibration exposure in wheelchair users is excessive (14). Hinges are placed at the front of the seat, and elastic elements are placed at the back of the seat. The elastic elements act to provide some suspension. The flexible element for the suspension can use either metal springs or polymer dampeners. Elastic elements have not necessarily resulted in lower levels of vibration being transmitted to the user (15). In addition, the shock absorption can result in lost energy during propulsion. This can occur because the force generated by the wheelchair user during propulsion goes toward compressing the elastic elements rather than forward motion. Therefore, the decision to purchase a suspension wheelchair should depend on whether the patient prefers the drive, feel, and comfort of the wheelchair.


A number of components can be attached to both manual and power wheelchairs. The following list is focused on manual wheelchairs, but many of the components are found on power wheelchairs as well.


Most wheelchair users require support for their feet and lower legs. This support is provided by footrests. Footrests may be fixed, folding, swing-away (see Fig. 78-2), or elevating. The footrests must provide sufficient support for the lower legs and feet, and must hold the feet in proper position to prevent foot drop or other deformities. It is essential to assess limitations in knee and foot range of motion. Some users have very tight hamstrings, requiring that the feet be positioned closer to or under the front edge of the seat. This is difficult to accomplish in most configurations. Extending the knees out to accommodate the standard design of the footrest position in front of the seat results in a sitting posture with a posterior pelvic tilt and a tendency to slide forward in the seat. This is commonly seen in elderly people in nursing homes using depot-type wheelchairs.

The feet must remain on the footrests at all times during propulsion, and therefore some type of cradle is recommended. Some wheelchairs (primarily those with swing-away footrests) use foot stirrups behind the heels of each foot (see Fig. 78-2). However, for other wheelchairs, it is best to use a continuous strap behind both feet because the rider’s feet sometimes come over the stirrups during active use. The frame should be selected and configured so that the feet sit firmly upon the footrests, with shoes on, without lifting the upper legs from the seat cushion. Footrests are commonly placed between 25 and 50 mm (1 to 2 in.) from the ground to ensure that sufficient ground clearance is maintained. Often, the footrests are the first part of the chair to come in contact with an obstacle (such as a door, wall, or another chair), so they must be durable.

Rigid wheelchairs often use simple tubes across the front of the wheelchair. By using a tubular rigid footrest, the wheelchair becomes stiffer and stronger (see Fig. 78-4). Rigid footrests are used during sports activities and work well for people who are very active in their wheelchair. Forward antitip rollers can be mounted to rigid footrests. This is helpful for playing court sports and reducing the risk of some forward-tipping accidents. Folding wheelchairs often use footrests that fold up and leg rests that swing out of the way to ease in transfers. Swing-away leg rests are not as durable as rigid ones. In some cases, manufacturers design swing-away leg rests that will flexibly bend on impact. This helps to absorb the energy of the impact and possibly prevent serious injury to the wheelchair rider. Elevating leg rests can be used for people who can not maintain a 90-degree knee angle or who need their legs elevated for venous return. Elevating leg rests make the wheelchair longer and heavier. This also has the effect of making the wheelchair less maneuverable by increasing the turning radius. Therefore, if elevating leg rests are needed, a power wheelchair should be strongly considered.

Armrests and Clothing Guards

Armrests provide a form of support and are convenient handles to hold onto when the rider leans to one side or the other.
Armrests are also helpful when attempting to reach higher places. For example, some people use their removable armrests as a tool to nudge items off high shelves. Armrests are commonly used to perform a “push-up” to assist with seat pressure relief. However, this is not the preferred method of pressure relief because of the significant stress it puts on the upper extremity (16).

There are three basic styles of armrests: wraparound, full-length, and desk-length. Wraparound armrests mount at the back of the wheelchair onto the frame below the backrest in most cases. The armrest comes up along the back of the backrest supports and wraps around to the front of the wheelchair. The major advantage of this design is that the armrest does not increase the width of the wheelchair like the other types of armrests. Wraparound armrests are popular among active wheelchair users. The most significant drawback of this design is that the armrest does not serve as a side guard to keep the rider’s clothing away from the wheels; although a removable piece of plastic called a clothing guard can be attached to the wheelchair frame to prevent clothes from getting caught in the wheels.

Full-length and desk-length armrests are similar in design, the main difference being the length of the armrest. Full-length armrests provide support for nearly the entire upper arm. They are popular on electric-powered wheelchairs because they provide a convenient and functional location for a joystick or other input device. Full-length armrests make it difficult to get close to some tables and desks. This is why manufacturers produce shorter desk-length armrests. Both of these types of armrests include clothing guards to protect clothing from the wheels. These types of armrests are mounted to the side of the wheelchair and may add as much as 5 cm (2 in.) to the width of the wheelchair.

Armrests can be fixed or height adjustable. Heightadjustable armrests may move up and down to accommodate the length of the rider’s trunk and arms. Most armrests can be moved in order to provide clearance for transferring in and out of the wheelchair and to allow a person to lean over the sides of the wheelchair. Armrests are either removed or flipped back. Both styles commonly use a latch, which is operated by the user. It is important to have secure latches on the armrests because armrests form convenient places for people to hold onto when attempting to provide assistance. If the armrests and latches are designed properly, two people can lift the rider and wheelchair by holding onto the armrests. In some cases, armrests are designed to pull out if any upward force is applied to them. These are not intended to be used for lifting the chair. It should be noted that armrests could alter the way in which a person propels a wheelchair. The hands and arms must clear the armrest in order to reach the push rim. This can force the user into excessive abduction at the shoulder, which could be a risk factor for injury.

Wheel Locks

Wheel locks act as parking brakes to stabilize the wheelchair when the rider transfers to other seats and when the rider wishes to remain in a particular spot. When locked, they keep the wheelchair stable to allow the rider to push things from the chair. There are a variety of wheel locks used to restrain wheelchairs when transferring or parking. High-lock brakes, which are located near the front corner of the seat, on the upper tube of the wheelchair’s side frame, are most common; however, location can vary. High-lock brakes require the least dexterity to operate. Extension levers can be added for people with limited reach or minimal strength. Wheel locks are standard equipment on wheelchairs, and they are simple to mount if the wheelchair does not come equipped with locks from the manufacturer.

Wheel locks may be push-to-lock or pull-to-lock. Most people prefer push-to-lock because wheel locks are more difficult to engage than to disengage. Riders often find it easier to push with the palm than pull with the fingers. Low wheel locks are usually mounted to the lower tube of the wheelchair’s side frame. Low wheel locks require more mobility to operate. They also alleviate the common problem that is seen with high wheel locks of the user hitting his or her thumb against the lock. This problem can be addressed for high wheel lock users by selecting retractable (i.e., scissors or butterfly) wheel locks. The retractable type of wheel lock helps to prevent jamming the thumbs and can also accommodate a wide variety of camber angles. The major drawback of retractable wheel locks is that they are more difficult to use than other types of wheel locks. The wheel lock must be positioned properly with respect to the wheel in order to operate effectively. If the wheels are repositioned, then the wheel locks must be repositioned. Tire pressure also affects the locking grip of these wheel locks. Many active manual wheelchair users will choose not to use armrests or wheel locks. Although these devices can be convenient, any equipment added will increase the overall weight of the chair, making propulsion more difficult.


A variety of options exist with respect to tires. The most common type of tire is pneumatic. These tires are lightweight and provide cushioning against impact and vibration from rolling over surfaces. This cushioning may increase rider comfort and improve wheelchair durability. Pneumatic tires are recommended for outdoor usage. The main downside of pneumatic tires is that they require maintenance and they can puncture. Tire pressure needs to be kept at a predetermined level because it is critical to rolling resistance, which can be related to risk of secondary injury associated with manual wheelchair use. A study has shown that when propelling on tires that were deflated by 50%, energy expenditure increased by 25% (17). Clinicians involved with wheelchair users should squeeze their patients’ tires to assure that they are keeping up with this important regular maintenance issue.

An alternative to pneumatic tires is solid inserts. These foam inserts fit into the pneumatic tire and replace the air-filled inner tube that would normally be there. They add some weight to the chair and may slightly worsen performance but are a good alternative for individuals who do not want to be
responsible for maintenance of air pressure. A less viable alternative is solid tires. These tires require no maintenance and are low in cost. Unfortunately, they make for an uncomfortable ride as all ground shocks are transmitted to the wheelchair user.

Additional Features

Many additional features are available that are unique to manual wheelchairs.


Antitippers are often placed on wheelchairs to assure they do not tip over backward. These can inhibit the ability to climb curbs, but they do offer a measure of safety. It is suggested that these be ordered for all wheelchairs and then have the user take them off when they are comfortable with the stability of the chair. A new antitipper is currently being developed but not yet commercially available that allows the wheelchair user to perform a wheelies and other skills. This device is folded up to allow the wheelchair user to perform his or her necessary wheelchair mobility skills, however; if the wheelchair user falls too far backward, the antippers will extend and prevent the wheelchair user from falling backward (18).

Push Rims

A number of different push rims are currently available, and new styles are likely to be introduced into the market. Anodized aluminum rims are the current standard on most K0004 and K0005 chairs. Less expensive chairs may come with plastic push rims. For individuals with difficulty gripping the rim, alternative rims should be considered. These can include vinyl-coated rims, rims with projections (Fig. 78-5), and rims wrapped with surgical tubing. All of these rims have the advantage of increased friction, making it easier to push the chair forward. Unfortunately, this increased friction can lead to burns when the wheelchair user attempts to slow down the chair. There is ongoing research into advanced ergonomic push-rim designs that allow for easier propulsion as well as braking (19). For individuals who have good hand function, a push rim called the “Natural-Fit” (Three Rivers, LLC, Mesa AZ) (see Fig. 78-4) is an ergonomically designed hand rim that has been shown to decrease stresses placed on the upper extremity during wheelchair propulsion (19).

FIGURE 78-5. Wheelchair push rims: (left) quad-knob or projection rim, (center) vinyl-coated rim, (right) anodized aluminum rim.

May 25, 2016 | Posted by in PHYSICAL MEDICINE & REHABILITATION | Comments Off on Wheelchairs

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