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Assistive Devices for Service Members With Disabilities

Chapter 26

ASSISTIVE DEVICES FOR SERVICE 

MEMBERS WITH DISABILITIES

RORY A. COOPER, PhD*; ROSEMARIE COOPER, MPT, ATP†; ERIK J. WOLF, PhD‡; KEVIN F. FITZPATRICK, MD, CPT§; 

GARRETT G. GRINDLE, MS¥; and JOHN J. COLTELLARO, MS, ATP¶

INTRODUCTION

WHEELCHAIRS: SELECTION, FITTING, AND SKILLS TRAINING

SEATING SYSTEMS

SPORTS AND RECREATION EQUIPMENT

TRANSPORTATION 

REHABILITATION ROBOTICS

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION

COMPUTER ACCESS

ELECTRONIC AIDS TO DAILY LIVING

VETERANS WITH DISABILITIES AND RECREATIONAL SPORTS EQUIPMENT

SUMMARY

*

Senior Career Scientist, US Department of Veterans Affairs, and Distinguished Professor, Department of Rehabilitation Science and Technology, University of Pittsburgh, 5044 Forbes Tower, Pittsburgh, Pennsylvania 15260

†

Assistant Professor, Department of Rehabilitation Science and Technology, University of Pittsburgh, Center for Assistive Technology, Forbes Tower, 

Suite 3010, 3600 Forbes Avenue, Pittsburgh, Pennsylvania 15213

‡

Research Engineer, Department of Physical Medicine and Rehabilitation, Walter Reed Army Medical Center, Building 2A, Room 146, 6900 Georgia 

Avenue, NW, Washington, DC 20307

§

Major, Medical Corps, US Army; Physiatrist, Department of Othopaedics and Rehabilitation, Walter Reed Army Medical Center, 6900 Georgia Avenue, 

NW, Washington, DC 20307

¥

Research Associate, Department of Rehabilitation Science and Technology, University of Pittsburgh, Human Engineering and Research Labs, 7180 

Highland Drive, Building 4, Second Floor East Wing 151R7-H, Pittsburgh, Pennsylvania 15206

¶

Clinical Instructor, Department of Rehabilitation Science and Technology, University of Pittsburgh Center for Assistive Technology, Forbes Tower, Suite 

3010, 3600 Forbes Avenue, Pittsburgh, Pennsylvania 15213
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Care of the Combat Amputee

INTRODUCTION

Assistive devices provide essential support for 

people with disabilities, allowing them to participate 

in community, vocational, and recreational activities 

and to perform activities of daily living (ADLs). A 

service member with a severe disability will likely 

rely on a variety of assistive devices to maximize 

function and independence. It is critical to properly fit 

the technology to the individual and train the user to 

effectively manipulate it. The availability of transportation (personal or public), accessible housing, personal 

assistance services, and assistive technology (AT) are 

among the most critical factors to be addressed once 

the acute rehabilitation phase has been completed.

A team approach is most effective when assessing 

an individual for AT. Ideally, the clinical team includes 

a physiatrist, therapists (physical, occupational, and 

speech), a rehabilitation engineer, a vocational rehabilitation counselor, and a rehabilitation technology 

supplier. The service member and family should be 

at the center of the team and ultimately decide on the 

most appropriate technology. This will often require 

patient education, but eventually many people with 

disabilities gain considerable knowledge about their 

AT needs.

The goal of AT is to allow the individual with the 

disability to perform activities as independently as 

possible in a variety of situations and environments. 

A thorough AT assessment includes evaluating the 

individual’s physical abilities (eg, strength, endurance, 

flexibility), cognitive abilities (eg, decision making, information processing, comprehension), sensory function (eg, vision, hearing, sensation), living environment 

(eg, home, work, school), support systems (eg, family 

assistance, paid assistance), and affect (eg, acceptance 

of disability, participation in process).

AT has been shown to be associated with successful rehabilitation outcomes. As injuries become more 

severe and the resulting disabilities greater, an individual’s need for AT grows. Social support becomes more 

important as the severity of the injury and disability 

increases. Although there are methods for severely 

injured service members to receive paid personal assistance, it is often family members who provide the 

bulk of their care, especially in the early years. AT provides independence and reduces the exertion placed 

on others. For example, powered wheelchair seating 

functions can allow an individual with a disability to 

change position to increase comfort or alter pressure 

without relying on the assistance of others.

When making recommendations for AT, consideration must be given to the home environment and fixed 

and movable features.1–3 Ramps, stair lifts, and widened doorways may be needed to allow effective use 

of some devices within the home. Moveable features, 

such as furniture, can be rearranged to allow access 

pathways through the home and, in some cases, may 

need to be replaced. For example, it is more difficult to 

get in and out of a soft low couch than a higher recliner 

with armrests. Community activities also need to be 

included in a thorough evaluation. Community-based 

tasks, such as shopping, using automated teller machines, and eating in restaurants, all provide important 

insight into AT needs and associated training. It is also 

important to provide exposure to integrated activities, 

such as skiing, hand cycling, swimming, and playing billiards, because they build self-confidence and 

help individuals adjust to a new self-image. It is easy 

to forget that travel is also an important community 

activity. Individuals with disabilities should be taken 

to events during their rehabilitation that require an 

overnight stay in a hotel so they can learn to perform 

tasks outside the structure of their homes.

Very severely injured soldiers and their families 

present with some unique needs and situations. Typically, severely injured soldiers must adjust to loss at 

a young age. These losses may include limbs, bodily 

functions, friends, and separation from the military 

unit that has served as a source of support. Losses may 

be complicated by the service members’ duty status 

(National Guard, reserve, active duty) and proximity 

to their duty stations or homes. Soldiers and their 

families have unique social support systems, such as 

their units, other soldiers, veterans’ service organizations, various Department of Defense programs, and 

the Department of Veterans Affairs. Each can make 

important contributions and bring resources to the 

severely injured soldier. It is also important to consider 

the preinjury socioeconomic status of the severely injured soldier, because this may impact the ability of the 

family to provide support and therefore influence the 

living environment. Soldiers have a unique occupation 

and even after sustaining severe injury, some want to 

return to active duty. AT may help some individuals 

pursue this career choice, while others may need to be 

guided toward other occupations.

Individuals with lower limb loss are likely to use 

multiple assistive devices, and the types of devices 

they use are likely to change over the individual’s 

course of rehabilitation and lifespan. Nearly all service members with lower-extremity amputations will 

start out using wheelchairs, often in combination with 

prosthetic limbs. The wheelchair will serve as their 

source of mobility as they learn prosthetic ambulation 

skills. Some people will progress to the point where 
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Assistive Devices for Service Members With Disabilities

they will only require the wheelchair on rare occasions 

(eg, people with unilateral transtibia amputations), 

whereas others may decide to use their wheelchairs as 

their primary means of mobility (eg, those with short 

bilateral transfemoral amputations). Over a lifetime, 

comorbid conditions may make it necessary to rethink 

the individual’s technology needs. For example, a 

manual wheelchair user may transition to an electricpowered wheelchair (EPW) because of severe shoulder 

pain from repetitive strain injury,4–9 or a prosthetic-limb 

user may transition to a manual wheelchair because of 

reduced metabolic capacity.10–14 A substantial challenge 

for service members to overcome is their own perceptions of disability and their potential to reintegrate into 

society, including active duty, and to return to an active 

lifestyle. Few service members have experience with 

disability, and many may base their views on popular 

perceptions and stereotypes. One goal of rehabilitation 

is to help the wounded, injured, or ill service member 

adapt and objectively evaluate the pros and cons of 

AT in pursuing their life goals. 

Like other areas of rehabilitation, AT services are best 

provided using a team approach.2,15–17 Individuals with 

disablities and their families are critical members of the 

rehabilitation team, and they should set the goals. The 

ideal prescription process includes six steps:

1. The clinical team assesses the user’s impairments, diagnosis, prognosis, residual abilities, extent of social participation, goals of 

wheelchair use, financial resources, priorities 

(trade-offs will invariably be necessary), and 

dimensions.

2. The clinical team and user develop a generic 

list of ideal AT features. 

3. The ideal-feature list is compared with items 

available from a reputable manufacturer and 

that can receive reliable service.

4. The user tests the device under consideration in 

the presence of a member of the clinical team.

5. Once the appropriate AT has been selected, 

the user is trained in its optimal use (including static indoor and outdoor challenges, or 

simulations thereof) and the results of training are documented.

6. After the AT has been used for a few months 

(and periodically thereafter), the situation 

should be reviewed and adjustments made.

Ideally, an AT team includes a physician, therapist, 

AT supplier, and rehabilitation engineer. Each professional has a unique but complementary role and, in 

cooperation with the end user, provides a comprehensive view of the AT needs. Physiatrists make the best 

physicians on AT teams because of their residency 

training and the opportunities that AT provides to 

benefit people with disabilities. The increasing complexity of AT selection, justification, fitting, tuning, 

and training requires specialized knowledge. Physical therapists are well qualified to assess physical 

capacities and limitations, especially as they affect 

mobility. Occupational therapists can assess functional capacity and deficits in performance of basic 

and instrumental ADLs. It is important to know how 

people perform tasks, where they are deficient, and 

how AT can compensate for the deficits in order to 

augment task performance. Rehabilitation engineers 

have an important role in understanding the capabilities and application of various technologies to assist 

in the selection process and product design. It is also 

important to include a qualified equipment supplier 

early in the rehabilitation process because the supplier 

will be familiar with the available devices and how 

they can be applied to solve problems. 

The Rehabilitation Engineering and Assistive 

Technology Society of North America (RESNA) acknowledged the need for consumers and insurers to 

recognize individuals with relevant experience and 

specialized knowledge. RESNA has created three 

levels of credentials to help enssure that consumers 

and insurers receive reliable information about AT. 

The AT supplier credential is intended for distributors and manufacturer representatives of AT. This 

is the most important credential offered by RESNA 

because it has started to bring order to an area of 

AT that was previously largely unregulated; before 

RESNA created the certification, there was no reliable 

credential for a supplier or manufacturer representative to demonstrate competency, and no way for 

consumers to readily identify qualified suppliers. The 

AT professional credential is geared toward therapists 

(physical, occupational, speech–language, counselors, 

and special educators). This credential recognizes 

qualified clinicians for their specialized knowledge 

and expertise. For decades, rehabilitation engineers 

provided clinical services without formal recognition 

of their expertise and, in many cases, their services 

were not reimbursed by insurance agencies. The rehabilitation engineering technology credential addresses 

the needs of rehabilitation engineers and provides 

other professionals and consumers a way to recognize 

them. To obtain the rehabilitation engineering technology credential, the engineer must also have obtained 

the AT professional credential. All of the RESNA 

credentials require proof of relevant experience and 

a passing score on a comprehensive examination. The 

credentials appear to have improved the quality of 

available AT services.
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Care of the Combat Amputee

WHEELCHAIRS: SELECTION, FITTING, AND SKILLS TRAINING

Mobility devices, in particular wheelchairs and 

scooters, make up a significant portion of the assistive 

devices in use today.2 Manual wheelchairs are mainly 

used by individuals who have the necessary upper 

body strength, function, and stamina for everyday propulsion.7,10,14,18 Comorbid conditions, such as excessive 

body weight, overuse of the upper limbs, long time 

living with a disability, and poor health and nutrition, 

can impair a user’s ability to independently propel a 

manual wheelchair, making EPWs more functional. 

For individuals who cannot use power wheelchairs, 

a manual wheelchair is prescribed and mobility is 

facilitated by an attendant or caregiver.

Only wheelchairs that comply with RESNA or International Standards Organization standards should 

be recommended. These criteria are intended to ensure minimal quality.19 Best results are often obtained 

through independent testing conducted within a 

reputable testing laboratory. 

Manual Wheelchairs

Design is critical to a manual wheelchair user’s 

mobility because upper body strength needs to be sufficient to bear the load of the wheelchair in addition 

to the individual’s bodyweight.4,5,7,9,19 Standard manual 

wheelchairs (typically used in hospitals and nursing 

homes) tend to be bulky, heavy, and generically sized. 

They have the benefit of folding, which allows for 

simple storage and transportation. However, the seat 

and backrests are sling upholstery, which provides 

little comfort and does not relieve pressure. These 

wheelchairs are not intended for long-term use, but 

rather for temporary use of less than a few hours a day. 

Strong, ultralight wheelchairs have been designed for 

individuals requiring long-term use.2,19–21 These wheelchairs can be customized to fit the user, allowing for 

better comfort and mobility. They are typically made of 

materials such as aluminum and titanium rather than 

the heavy steel used in standard wheelchairs (Figures 

26-1 and 26-2). Ultralight manual wheelchairs are often 

appropriate for soldiers, who tend to be very active.

The basic features of an ultralight wheelchair include adjustable seat height, width, and depth; backrest height; armrest height; seat and back angles; rear 

wheel camber; and rear axle position (Figure 26-3). 

Lightweight wheelchairs have limited adjustability 

and standard wheelchairs have no adjustability. Manual wheelchair frames are made of aluminum, highstrength steel alloy tubing, titanium, and lightweight 

composite materials. The frame structure affects durability, transportability, and storage. For example, rigid 

Figure 26-1. A standard manual wheelchair with a folding 

steel frame and sling seat.

Figure 26-2. An ultralight manual wheelchair with a rigid 

titanium frame.
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Assistive Devices for Service Members With Disabilities

Figure 26-3. Key dimensions of an ultralight manual wheelchair: axle position, seat height, seat depth, backrest height, 

and footrest length. 

frame chairs are one piece with removable wheels and 

foldable back supports for transport and storage, while 

cross-brace frames allow the wheelchair to collapse in 

the middle for storage. Some frames have suspension 

elements to decrease shock and vibration and make 

for a smoother overall ride.22

In some instances, none of the previously mentioned 

wheelchairs meets the needs of the user. For example, 

obese or overweight individuals need a larger, stronger wheelchair to support their weight. This class of 

wheelchairs is called heavy-duty or bariatric. They 

can support individuals ranging from 300 to 1,000 

pounds. 

Seat Height

Seats should be positioned so that leg length is accommodated, leaving about 50 mm under the footrest 

for obstacle clearance. Seat height needs to be at a level 

that allows the individual the necessary knee clearance 

to fit under tables, counters, and sinks.

Seat Depth

Seat depth provides support for the thighs. There 

should be about 50 mm behind the popliteal area of 

the knees. Improper depth may cause increased pressures on the thighs or buttocks. Shallow-depth seats 

increase sitting pressure because there is less contact 

between the thighs and seat, which may decrease the 

overall pressure distribution. If the seat depth is too 

great, pressure behind the knees and on the calves is 

increased.

Seat Width

The width of the wheelchair seat should be slightly 

larger than the user’s buttocks (about 25 mm). The 

hands should be able to just slip between the hips and 

the side guards or armrests. If the seat is too narrow, 

pressure increases on the sides of the hips, which may 

result in pressure sores. If the seat is too wide, the user 

will be forced to use a more abducted arm position for 

propulsion and will have more difficulty negotiating 

doorways and narrow passages.

Back Height

A wheelchair’s back height depends on comfort and 

the amount of postural support needed. The backrest 

should be low enough that it does not impede the range 

of motion of the arms during propulsion. If the backrest 

is too high, the user will not be able to contact as much 

of the pushrim; if it is too low, the user will not have 

the necessary postural support and may experience 

discomfort or long-term deformity.

Seat and Back Angles

Seat angle is the horizontal angle between the seat 

and back, and back angle is the vertical angle between the seat and back with respect to vertical. Both 

are selected or adjusted to provide the most comfort 

and support for the user. Increasing the seat dump 

(declining the seat toward the rear) can help stabilize 

the pelvis and spine, which may improve propulsion. 

However, too much dump may increase the sitting 

pressure on the ischial tuberosities and make it more 

difficult to transfer from the wheelchair. Increasing 

the back angle is another way to ensure user comfort. 

If an individual has difficulty with hip flexion, the 

back can be opened to alleviate discomfort. However 

reclining too far can shift the center of gravity, making 

the chair unstable.

Armrests and Footrests

There are a variety of armrest lengths and styles. 

The armrest should be positioned at a comfortable 

height so the arm lies parallel to the ground. Armrests 

that are too high or too low may cause discomfort in 

the user’s neck and shoulders. Many ultralight wheelchair users prefer not to have armrests because they 

tend to increase the overall width of the wheelchair, 

cause the arms to abduct more during propulsion, and 
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Care of the Combat Amputee

may inhibit access to desks and tables. Cross-brace 

framed chairs typically have foot rests that can flip 

up or down, swivel, are angle-adjustable, or can be 

removed, while rigid-framed chairs have the footrest 

built into the frame. Although these footrests cannot 

typically be removed, they can be slightly adjusted to 

accommodate various leg lengths.

Wheels and Tires

A typical manual wheelchair has four wheels, two 

large rear wheels and two small front wheels called 

“casters.” The casters are usually solid rubber, but 

can be polyurethane, pneumatic, or a combination. 

Caster size varies from 50 mm to 200 mm in diameter, 

depending on the wheelchair type and user preference. 

The standard rear wheel is a pneumatic 24-inch (0.6096 

m) tire. Different tire types are available, such as solid 

insert tires, semipneumatic, or synthetic. Ultralight 

wheelchairs have quick release axles so the wheels can 

be easily removed for repair, storage, and transport.

Rear Wheel Camber

Camber is the amount of rear wheel vertical angle. 

At 0° camber, the wheels are vertical. To increase camber, the top of the wheel is tilted inward, moving the 

bottom of the wheel outward. Ultralight wheelchairs 

have up to 8° of camber, but about 3° camber is typical. 

Increasing camber provides more stability at the cost 

of increased wheelchair width. More than 8° camber is 

seen on many special-purpose sport wheelchairs.

Rear Axle Position

The rear axle position can be adjusted or selected 

horizontally and vertically. Horizontal positioning 

affects propulsion ability and technique. Placing the 

axle position forward allows users to grasp more of 

the wheel during propulsion. Moving the position 

further back limits the amount of pushrim that the individual can reach. Moving the axle forward increases 

the tendency of the wheelchair to tip backward. Users 

can take advantage of this feature to perform wheelies 

(when a manual wheelchair user lifts the front wheels 

from the ground by applying forward force to the 

pushrims and maintains balance on the rear wheels 

by forward and backward forces on the pushrims) 

and traverse obstacles more easily. Antitippers can be 

added to reduce the risk of tipping backward. Forward 

axle position also decreases the number of strokes and 

amount of effort used for propulsion. 

Vertical axle adjustments can provide similar 

propulsion advantages. Moving the axle position up 

with respect to the seat lowers the seat height, which 

improves stability. However, if the seat is too low, arm 

abduction can lead to poor propulsion patterns. An appropriately placed axle can lower the stress on the arms 

that results from everyday wheelchair propulsion. 

Manual Wheelchair Propulsion and Skills 

Various features of a manual wheelchair can affect a 

user’s overall propulsion capability.6,13,21,23 Wheelchair 

propulsion can be broken down into two components: 

the propulsion phase and the recovery phase. The 

propulsion phase begins with the initial hand contact 

on the pushrim and ends with the release of hand 

contact from the pushrim. The recovery phase begins 

with the release of hand contact from the pushrim 

and ends with the hand contact onto the pushrim.21

Individual propulsion styles impact push frequency 

(the number of times the pushrim is contacted over a 

given distance or for a given time), push length (the 

distance the hand travels while in contact with the 

pushrim), push force (the magnitude of force applied 

to the pushrim in multiple dimensions), and the speed 

(the distance the wheelchair moves over a given time). 

Understanding and recognizing the effects of these key 

components in an individual’s wheelchair propulsion 

style reduces the risk of secondary repetitive strain 

injuries associated with wheelchair prolusion.5,6,21,24

Ultimately, the user should be trained to use a smooth, 

long stroke; a semicircular pattern that corresponds to 

a decreased push frequency with more time spent on 

the pushrim; decreased forces; and increased propulsion efficiency.21,25

Manual wheelchair skills further enhance the user’s 

safety, efficiency, and independence. Maneuverability 

and adaptability in multiple environments are key 

goals of wheelchair skills training. Training may begin 

with basic skills, such as negotiating obstacles, turning 

in tight areas, and opening and closing doors—skills 

needed to allow a person to conduct all mobilityrelated ADLs within their homes. Eventually, training 

advances to higher-level skills, including wheelies. The 

wheelie position is useful for transiently reducing the 

loads on the ischial tuberosities, decreasing neck discomfort when talking to a standing person, turning in 

tight spaces, and negotiating obstacles, such as rough 

or soft ground, inclines, and curbs.

Although engaging in an active lifestyle is beneficial 

for maintaining quality of life, a majority of wheelchair 

users are inactive. Using a custom logging device, 

Tolerico et al studied the wheelchair activity patterns 

of 52 veterans at the National Veterans Wheelchair 

Games and in their home communities for a period of 

13 to 20 days.12 They found that individuals traveled 
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Assistive Devices for Service Members With Disabilities

2,457 m/d, at an overall average speed of 0.8 m/s, over 

8.3 h/d. Veterans who were employed covered more 

distance, accumulated more minutes of movement, 

and traveled a greater distance between consecutive 

stops than those who were unemployed. Cooper et al 

examined the activities of two groups of power wheelchair users over a 5-day period.26 Results indicated that 

the group of individuals who attended the National 

Veterans Wheelchair Games was more active in terms 

of distance and speed traveled compared to a group 

of subjects monitored in their home environments 

(Pittsburgh, Pennsylvania). Fitzgerald et al tracked the 

activities of community-dwelling manual wheelchair 

users who used pushrim-activated, power-assisted 

wheelchairs and personal wheelchairs.13 No significant 

differences were found in the distance and speed traveled using either wheelchair. Hoover et al27 collected 

data from both the National Veterans Wheelchair 

Games participants and those in their home environments. The speed at which the power and manual 

wheelchair users traveled was 0.711 m/s and 0.3092 

m/s, respectively.

A properly fitted manual wheelchair used by a 

well-trained and skilled individual can provide a high 

degree of mobility. Many service members with lower 

limb amputations can develop remarkable wheelchair 

skills. Tasks such as negotiating curbs, escalators, stairs, 

uneven terrain (sand, grass, and gravel), slopes, and 

narrow spaces are all teachable skills. Wheelchair skills 

training is a critical component of the rehabilitation 

and mobility training of individuals with lower limb 

amputations. Individuals with lower extremity amputations should be thoroughly assessed for wheelchairs 

and provided training in their use (Figure 26-4).

Electric-Powered Wheelchairs

EPWs are indicated for a wide range of individuals with disablities.28–30 For some individuals with 

severe sensory–motor impairments (eg, individuals 

with high-level tetraplegia, traumatic brain injury, or 

multiple amputations), EPWs are the only functional 

mode of mobility.28,29,31 Sensory–motor impairments 

can limit functional motor control to individual parts 

of the user’s body. In these cases, EPW input devices 

must be customized to take advantage of the user’s intact motor function.26,29,32 Microswitching mechanisms 

that can be activated with the mouth (sip-and-puff) or 

other parts of the body (feet, head, etc) must be used 

as controller input. EPWs are also indicated for people 

who are at risk of falling or in pain when ambulating 

and who cannot safely or functionally propel a manual 

wheelchair. For these individuals, the EPW represents 

a safe and pain-free means of mobility.33 For all users, 

Figure 26-4. Wheelchair athlete demonstrating advanced 

mobility skills.

the goal of the EPW is to provide greater independence and quality of life.2,30,34,35 As EPWs have become 

more technologically advanced, they have been able 

to serve this need for a broader range of people with 

disabilities.30,31,34,35 Because people with disablities have 

diverse and complex needs to achieve independence, 

customizable EPWs can reach a larger proportion of 

the population with disabilities.19,36 The technological 

advances of controller programmability, special seating 

systems, and integrated control units (with augmentative communication devices, environmental control 

units, etc) have allowed a wider population of people 

with disabilities to become independent. 

There are two types of EPW frame designs: traditional (based on a manual wheelchair design) or 

power-base. Because the manual wheelchair design 

predates the power wheelchair, the first designs for 

power wheelchairs included simple power devices 

added on to manual wheelchairs (Figure 26-5). These 

devices still exist, especially for portable EPWs that 

can be easily disassembled, but the majority of EPWs 

are power-base styles. The conventional frame design 

was an easy first step in EPW development, but adding special seating features (eg, tilt and recline) made 
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Care of the Combat Amputee

Figure 26-5. A traditional power wheelchair.

the wheelchair heavy and unstable. To accommodate 

these additional features, the EPW was redesigned 

in a two-component power-base style. The bottom 

power-base component houses the batteries, motors, 

and, in most cases, the controller. The seat component 

attaches to the power base, and thus can be swapped 

for whatever style of seat best meets the user’s needs. A 

secondary benefit of separating the seating and power 

and control system is that the power-base design can be 

optimized nearly independently of the user’s seating 

requirements. Consequently, power-base designs have 

progressed rapidly to include complex suspension 

systems, a low center of gravity, and excellent maneuverability. Likewise, seating technology has advanced 

to meet the needs of a wide range of users.

An EPW seating system can be as low-tech as a 

captain’s chair or as complex as a power-actuated seat, 

which has any combination of the following features: 

tilt (changing the whole seat angle relative to the horizontal), recline (changing the seat-back to seat-bottom 

angle), elevating leg rests (leg-rest-to-seat-bottom 

angle), seat elevator (changing the height of the seat), 

and a standing mechanism (raising the person into a 

standing posture). Depending on the user’s pressure 

management needs and musculoskeletal system state, 

any combination of the above motions may be prescribed. Seat tilt is one of the most common features 

because it allows pressure to be shifted from the buttocks to the back, which can prevent the pressure ulcers 

common to wheelchair users with sensory loss.

Power-Assisted Wheelchairs

Power-assist devices include standalone-powered 

units external to the wheelchair that the wheelchair 

user holds onto, power add-on devices that attach to 

the wheelchair and have steering mechanisms or input devices for control, or pushrim-activated systems 

(PASs) with motors in the wheelchair hubs (Figure 26-

6).14,36,37 A PAS operates much like a manual wheelchair 

but requires less effort,11,14 making it suitable for people 

with, or at risk for, upper extremity joint degeneration, 

reduced exercise capacity, and low upper-extremity 

strength or endurance.

One type of PAS measures pushrim forces using a 

linear compression spring and a simple potentiometer 

that senses the relative motion between the pushrim 

and the hub. A microprocessor uses these signals to 

control a permanent magnet direct current motor attached to each rear wheel. Each motor is connected to 

Figure 26-6. A pushrim-activated, power-assist wheelchair.
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Assistive Devices for Service Members With Disabilities

a ring gear, resulting in a 27:1 gear reduction. The PAS 

controller provides the feel of a traditional manual 

wheelchair by simulating inertia and compensating for 

discrepancies between the two wheels (eg, differences 

in friction), and increases user safety with an automatic 

speed limiting and braking system through the use of 

regenerative braking. Power is supplied by either a 

single, custom-designed, nickel–cadmium battery or 

a nickel–metal hydride battery. 

system enable the user to remain balanced even during 

perturbations. For example, if a user shifts forward to 

reach something off a shelf, the transporter responds 

by bringing the wheels forward to compensate for 

the change in the occupant’s center of gravity and 

to keep the occupant balanced. Although driving is 

possible in this configuration, the main purpose of 

the balance mode is to enable users to interact at eye 

level with their able-bodied peers and to extend their 

reaching height. Remote configuration allows users to 

detach the joystick and drive the device into a vehicle 

for easier transport. The iBOT can be connected to a 

computer so system logs, errors, and software updates 

can be downloaded and uploaded. This feature allows 

a remote technician to connect to the transporter and 

determine and potentially fix problems related to its 

operation or perform software updates. 

The iBOT is the first stair-climbing device to appear 

on the market that does not use a track-based design. 

The major advantage of tracked-based stair-climbing 

wheelchairs is simple control and robustness in operation on irregular stairs. However, a disadvantage is 

the high pressure exerted on the stair edges and the 

difficulties associated with everyday use (it tends to 

be bulkier, heavier, and less maneuverable).

Figure 26-7. The iBOT transporter in standing mode.

Multifunctional Wheelchairs

Multifunctional wheelchairs are capable of changing drive configurations to adapt to environmental 

changes or challenges.31,38–41 An example of this is the 

iBOT transporter, which uses a two-wheel cluster 

design (Figure 26-7).38,40,41 With this design, the iBOT 

transporter can assume five different drive configurations: standard, four-wheel, balance, stair, and remote. 

In standard function, the transporter resembles a rearwheel–drive wheelchair by raising the foremost drive 

wheels and lowering the front casters. In four-wheel 

configuration, all four drive wheels are in contact with 

the ground and the front castors are elevated. This configuration enables the user to climb curbs (up to 10 cm 

high) and easily traverse uneven and sloped terrain. 

The stair-climbing ability is achieved by controlling the 

cluster rotation on the basis of the position of the center 

of gravity. The device strives to keep the system’s center of gravity above the ground-contacting wheels and 

between the front and rear wheels at all times, regardless of disturbances and forces operating on the system. 

Pitch-and-roll motion, recorded with gyroscopes, is 

used by a closed-loop control algorithm to drive motors to keep the seat level. The joystick is deactivated 

during stair climbing to prevent unintentional deflection. Users can initiate the function on their own and 

can maintain stability by holding the stair handrails, or 

assistants can control the rate of climbing through the 

assist handle. When a user or assistant leans forward 

or backward, shifting the center of gravity, the device 

rotates the wheel cluster, allowing the device to climb 

down or up one stair. The control system requires the 

device to dwell on each step for a few seconds before 

allowing another cluster operation. This hiatus helps 

keep the device from going out of control on stairs. 

The stair configuration performs well in descending 

and ascending stairs that are standard height, width, 

and depth.

In balance configuration, the clusters are rotated so 

that one set of drive wheels is positioned directly over 

the other set, leaving only two wheels in contact with 

the ground. The gyroscopes and closed-loop control 
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Care of the Combat Amputee

SEATING SYSTEMS

The human body is not designed to sit in the same 

position for prolonged periods of time.39 It alters its 

position frequently from various lying, sitting, and 

standing positions, depending on the task being performed. For people with disabilities who are unable 

to walk and require wheeled mobility and seating 

devices, sitting is necessary, and identifying the most 

effective seating system for a specific individual’s 

needs can be challenging. 

The human body is a dynamic structure that is designed to perform and engage in a number of tasks in 

a variety of positions. Even while in a lying position, 

the body frequently (and subconsciously) changes 

position. The same applies in a standing or seated position. In a standing position, the body is a constantly 

dynamic structure, able to change its base of support 

frequently depending on movement and placement of 

the feet (base of support) in relation to the torso. The 

same applies to the body in a seated position, where 

the pelvis and thighs act as the base of support and 

the hip joints are placed in a flexed position, resulting 

in a potentially unstable base of support. In a seated 

posture, the pelvis is free to tilt and rotate in multiple 

directions, ultimately affecting the position and posture of the rest of the upper body (including the spine, 

trunk, upper extremities, and head). The seated body 

is therefore dynamic but also unstable.

Before providing a seating system, an individual’s 

muscle strength, joint range of motion, coordination, 

balance, posture, tone, endurance, sitting posture, 

cognition, and perception must be assessed to obtain 

a basic understanding of the individual’s capacity 

and needs. These assessments should be performed 

by a qualified professional with specialty training, 

certification, and knowledge of wheelchair seating and 

mobility applications. A proper assessment begins with 

listening to the user’s needs, concerns, and goals for a 

device. Realistic goal setting fosters discussion related 

to the technology’s capabilities. 

The physical–motor assessment begins by observing and noting the person’s seated posture; this 

provides a baseline of the seated postures the user 

may assume. A person may sit in a particular position 

because of preference, limitations, or the design of the 

seating system. It is therefore necessary to move the 

person from the existing system to an unsupported 

seated position on a flat surface, such as a therapy 

mat table, to observe the individual’s posture without 

postural supports. If the user’s unsupported sitting 

balance is limited, the examiner may need to provide 

support. Careful attention should be paid to the individual’s pelvic and spinal alignment. While the person 

is sitting on the mat table, the examiner should apply 

appropriate forces (with the hands) to determine if 

observed deformities of the pelvis and spine are fixed 

or flexible. A fixed deformity cannot be corrected by 

a seating system and needs to be accommodated by 

the system. A flexible deformity can be corrected in 

varying degrees, depending on complexity, and needs 

to be supported by the seating system.

The user should then be asked to transition or be 

assisted to a supine position, where pelvic and spinal 

alignment can be reassessed with the pull of gravity 

working in a different plane on the body. Range of motion at the hips and knees should be assessed in this 

position. Limitations in hip flexion will affect the seatto-back angle configuration of the seating system. With 

the hip flexed, knee range of motion (especially extension) needs to be assessed, considering the hamstrings 

cross the hip and knee joints. This will determine the 

optimal angle of the leg rests and position of the feet. 

In either a seated or supine position, upper extremity 

strength and range of motion need to be examined 

using commonly accepted measures and procedures. 

During this assessment, it is also necessary to note the 

quality of movements related to coordination because 

it is affected by tone, spasticity, tremors, and primitive 

reflexes. 

Seating systems can be classified in three general 

categories: prefabricated, modular or adjustable systems, and custom contoured systems. Every user 

should be given a seating system designed and provided specific to the individual’s medical, functional, 

and personal needs. A system should address issues of 

soft tissue management, comfort, orthopaedic deformities, and maintaining vital organ capacity. Functionally, the system should address the movements the 

user needs to perform, such as reaching or accessing 

objects, transferring, getting under tables, and completing ADLs. This requires carefully matching critical 

chair dimensions to body dimensions, user ability, and 

intended use. The user’s goals and priorities need to 

be primary considerations; for example, a user may 

forgo pressure relief and comfort for a firmer system 

that provides greater stability and allows sliding off 

the seat for transfers. 

The simplest form of prefabricated or premanufactured seating system is a linear seating system. A linear 

seating system refers to a planar seat and back with 

fixed angles and orientations. These types of systems 

may not provide a great deal of contour or support; 

however, they may be indicated for users who need 

more freedom of movement or who will experience 

rapid changes in size. Generically contoured systems 
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Assistive Devices for Service Members With Disabilities

are indicated for people who have minimal to moderate postural support needs and who have body shapes 

and dimensions that fit within these generic contours. 

Modular systems are composed of components that 

can be adjusted, added, or removed to address a 

specific postural need, such as lateral trunk supports 

and thigh guides. These systems are ideal for people 

with progressive conditions, such as multiple sclerosis, 

whereby postural needs may increase over time. They 

are also indicated for conditions that might improve, 

such as stroke or brain injury. Modular components 

are also ideal when a user’s needs change throughout 

the day or activity. For example, a person may fatigue 

toward the end of the day and need more lateral trunk 

support added to the backrest, but may want these 

supports removed because they interfere with reaching 

activities or transferring out of the wheelchair. 

Custom molded and contoured systems are more 

complicated to design and apply clinically. These systems are indicated for people with moderate to severe 

fixed or semifixed postural deformities, including curvatures of the spine, pelvic obliquities, and windswept 

postures of the lower extremities. A disadvantage of 

custom seating is it may limit function and movement 

because the system is specific to body shape. There are 

also concerns with people who might grow, change, 

gain or lose weight, or have seasonal variations in the 

thickness of their clothing. Designing these systems requires liquid foam, molding bags, and computer-aided 

design or computer-aided manufacturing technologies. 

Seating systems should not attempt to overcorrect 

postural deformities, but should accommodate them. 

Reduction or correction of postural deformities and 

joint contractures is best addressed through other 

interventions, including surgery, controlled passive 

stretching, or orthotic devices. 

Seating systems are composed of several components, including at least a seat and back support. Other 

components often include supports for the arms, legs, 

and head. Adjustable features may include a reclining backrest, tilt-in-space ability, elevating seats, and 

standing capabilities.

Seat Support

The seat interface should balance pelvic stabilization and pressure distribution, allow for some degree 

of movement, and be functional to the individual’s 

needs. The seat is the base of support for the pelvis, 

which supports the rest of the upper body. A seat 

should have an underlying, rigid base of support. 

Sling seats, commonly found on standard manual 

wheelchairs, provide limited postural support and are 

intended to allow easy folding. Sling upholstery tends 

to stretch and bow over time, and may contribute to 

adduction and internal rotation of the hips as well as 

a posterior pelvic tilt and kyphotic posture. The angle 

and shape of the seat contributes to pelvic stabilization. Without stabilization, the pelvis tends to rotate 

posteriorly, causing the buttocks to slide forward in 

the seat. This can result in shearing forces in the buttocks and may lead the spine to further collapse into 

a slouched posture. Providing a posterior slope to the 

seat angle, wedging the seat, or designing an ischial 

shelf in the shape of the cushion can provide greater 

pelvic stabilization and a better sense of balance, but 

may not always be ideal. It could make it more difficult to slide forward out of the seat for transfers, 

increase pressure in the ischial tuberosity and coccyx 

regions, or promote greater posterior pelvic tilt if the 

back support is not adequate. A posterior slope may 

also be inappropriate for people who self-propel with 

their feet. However, wheelchair users sometimes want 

to slide forward in their seats, slouch to relax, and 

change position because sitting upright continuously 

is difficult and fatiguing.

Back Supports

Long-term collapsing deformities of the spine, 

including kyphosis and scoliosis, can compromise 

breathing and other vital organ functions. Properly 

applied back supports can slow the onset of these 

problems. Back supports can be categorized by their 

shape, height, and stiffness. The preferred backrest 

provides posterior and lateral support but does not 

inhibit movement in the trunk and upper extremities 

(which may be needed for the propulsion of a manual 

wheelchair or other activities, such as reaching). A 

contoured or curved back should accommodate the 

width of the user and follow the natural curves of 

the spine to provide enough trunk support without 

compromising movement or function. Standard slingback upholstery also tends to stretch over time, which 

can result in a posterior pelvic tilt and contribute to a 

kyphotic posture. Flat or planar backs allow for more 

movement, but might be uncomfortable and less stable 

because they do not provide lateral stabilization or 

conform to natural spinal curves. A high back provides 

greater support through the spine, but may interfere 

with trunk rotation and shoulder movements. Back 

supports below the scapulae and thoracic spine allow 

for greater freedom of movement, but may result in 

long-term spinal deformities. Fabric backs with adjustable tension straps are now more common, especially 

in manual wheelchairs, and tend to be lightweight 

compared to rigid, shell-back supports. They can be 

adjusted for varying needs and shapes; however, they 
706

Care of the Combat Amputee

stretch and wear out over time and do not provide 

rigid stabilization.

Current trends in backrest design focus on styles 

with taller backs, lateral curves around the thoraciclumbar regions, and cutouts in the scapular region to 

provide spinal support while allowing for shoulder 

movements. Attention is also being focused on using 

adjustable, durable, carbon-fiber materials to construct 

back supports. 

Arm Support

Arm supports may be necessary to rest the arms, 

provide a greater sense of lateral trunk stability, and 

decrease pressure loads in the buttocks by bearing 

weight through the upper extremities. They may also 

provide a place to hold onto with one hand while 

reaching with the other, and to push off of for weight 

shifts or transfers. Armrest assemblies can also contain 

the pelvis and thighs to keep the thighs in alignment, 

and can protect clothing and skin from rubbing on 

the tires of a manual wheelchair. However, armrests 

add weight to manual wheelchairs and can get in the 

way of accessing the pushrims for effective propulsion. Therefore, many active manual wheelchair users 

choose to forgo arm supports. If arm supports are used, 

they should be removable or capable of swinging out 

of the way. They should also be set at an optimal height 

for the user or be adjustable.

Foot Supports and Leg Supports

Foot supports and leg supports can be classified by 

the angle at which they position the knees and where 

they place the feet. Traditional swing-away footrests 

are designed to keep the user’s feet out in front, with 

about 60° to 70° of knee flexion, to avoid interference 

with caster swivel and rotation. This is not necessarily a natural seated position; it promotes slouching by 

pulling the hamstrings and the pelvis into a posterior 

pelvic tilt.

Elevating leg rests pose an even greater problem. 

A perceived purpose of elevating leg rests is to help 

manage edema (swelling) in the lower extremities. 

However, being seated in an upright position with the 

hips flexed and the knees extended does little to reduce 

edema unless the feet and legs can get to or above heart 

level, which can only be accomplished by tilting the 

seat back and reclining the backrest. Elevating leg rests 

without these features will also likely place greater 

pull on the hamstrings, promote a slouched posture, 

and cause significant problems for people with limited 

knee extension (Figure 26-8).

Some people (eg, active manual wheelchair users) 

prefer to sit with their knees at a more natural, 90° 

(or greater) flexed position, with their feet tucked 

under the seat to provide greater postural stability 

and shorten the length of the wheelchair for maneuverability. This position also warrants tapering the 

footrests inward to keep the feet from interfering 

with front caster swivel. In a power wheelchair, a 

front- or mid-wheel drive configuration positions 

the feet so the knees are flexed at 90° because front 

casters are not needed. Some active wheelchair users also prefer to have the foot supports fixed in a 

one-piece structure to add rigidity and durability. 

However, removable or swing-away foot supports 

should not be eliminated for people who stand for 

transfers out of the wheelchair or propel a manual 

wheelchair with their feet. 

Head Support

The head can be difficult to position because of its 

size and movements in the cervical spine or neck. A 

head support is warranted for those with poor head 

control. Prior to positioning the head, the pelvic and 

spinal support and balance should be addressed because the head is more distal to these structures and 

will tend to position itself based on their position. A 

head support is also almost always indicated in wheelchairs that include tilt and reclining backrests because 

the head needs to be supported in these positions. A 

head support may be warranted if the user needs to 

rest in the wheelchair and if the wheelchair is to be 

used as a seat in a vehicle (to provide support in the 

event of a collision). 

Figure 26-8. Elevating leg rests.
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Assistive Devices for Service Members With Disabilities

Like all other seating components, head supports 

come in various shapes and sizes to address different needs and preferences. Some people prefer to go 

without head support because it interferes with head 

movement and can reduce field of vision. Flat head 

supports provide a surface to rest against, while curved 

supports provide some degree of lateral stability. Wide 

head supports allow for greater area to place the head, 

but tend to interfere with field of vision. Head supports 

can be aggressive for people with poor head control 

(eg, those with amyotrophic lateral sclerosis), and may 

include lateral head and suboccipital supports. Head 

supports should be mounted to the seating system 

using adjustable hardware so they can be moved, 

adjusted, and removed as needed.

Tilt Frames and Reclining Backrests

Because it is unnatural to sit in one position for 

prolonged periods of time, tilt frames and reclining 

backrest systems are options that benefit those unable 

to move or reposition themselves effectively. These options redistribute pressure, manage posture and tone, 

provide comfort, and help with personal care activities. Tilt frames and reclining backrests are available 

for both manual and power wheelchairs and can be 

operated by the wheelchair user as a powered feature 

or manually by an attendant. 

Tilt allows the entire seating system to pivot posteriorly while keeping the hip and knee joints in the 

same position. This helps redistribute pressure away 

from the buttocks region and into the back support. 

It is also useful in repositioning because people tend 

to slouch and slide forward when sitting upright for 

prolonged periods of time. The trunk is able to extend 

in a tilted position, countering a kyphotic posture and 

potentially reducing or slowing the development of 

trunk and spinal deformities (Figure 26-9).

A reclining backrest allows the hip flexors to stretch 

and opens the hip angle to assist with attending to 

catheters, toileting, dressing, and dependent transfers. 

However, reclining the backrest creates shear forces in 

the seat and back because the user tends to slide down 

in the seating system. The addition of a tilt-in-space 

feature will counter this tendency and should be considered when recline is warranted. Both systems also 

allow a person to rest in the wheelchair without having 

to be transferred to a bed. Research supports use of 

combined tilt and reclining backrest interventions to 

optimally distribute pressure (Figure 26-10).

Standing Systems

Wheelchairs that allow the user to passively stand 

benefit individuals who would typically be unable 

to do so otherwise. The benefits of passive standing 

may include decreased bladder infections, reduced 

osteoporosis, and decreased lower extremity spasticity. In addition, there are likely psychological benefits 

resulting from the sensation of upright posture and the 

ability to interact at eye level, and functional benefits 

associated with being able to reach objects in higher 

locations. It is critical to carefully assess a person’s 

posture and range of motion prior to considering a 

standing device because those with range-of-motion 

limitations and postural deformities cannot stand 

upright. A candidate for a standing wheelchair should 

be carefully assessed by a physician or other qualified 

Figure 26-9. A powered tilt seating system. Figure 26-10. A powered reclining backrest system.
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Care of the Combat Amputee

practitioner before standing to address concerns with 

orthostatic hypotension in cases where people have 

not stood for a prolonged period of time. 

Seat Elevation Systems

Some of the benefits obtained from a standing 

system, such as reaching objects in higher locations, 

accessing high surfaces, and being at eye level with 

standing people, can be accomplished through the 

use of a seat-elevating system (Figure 26-11). This is a 

feature typically available only on power wheelchairs. 

Raising the seat is also sometimes critical to facilitate 

safer and more efficient transfers. For a person using 

a sliding board or performing a lateral transfer, a seat 

elevator allows for transfers in a downhill direction, 

which has been shown to require less strain on the 

upper extremities as compared to transferring to a 

level or higher surface. In other cases, the seat elevator can facilitate transfers for people who stand to 

transfer but have difficulty rising from a low seat to 

floor height.

SPORTS AND RECREATION EQUIPMENT

Figure 26-11. A seat elevator can be used to reach higher 

objects.

The human need for recreation is especially important in the presence of physical, sensory, or cognitive 

impairment that affects the ability to function in everyday activities and environments. Primary rehabilitation interventions emphasize self-maintenance, education, and employment activities. Recreation allows 

humans to challenge their physical limits in a setting 

that accepts new participants, provides instruction 

and emotional support for learning, includes social 

participation, and promises fun and escape from the 

realities of everyday life. Recreation puts humans in 

touch with their imagined self (eg, a person who is 

adventurous, strong, or graceful) and does not need 

to be justified in the same way as work and selfmaintenance activities; it is chosen just because it is 

appealing to the participant.42 Healthy competition 

with self and others through sports and recreation 

creates an arena for continuing the gains of medical 

rehabilitation, challenging personally held ideas about 

disability and handicap learned from culture, and testing out a new self-concept that can include acceptance 

of disability.43

Basketball wheelchairs are similar to typical manual 

wheelchairs but incorporate features to enhance stability and maneuverability. They are lightweight to allow 

for speed, acceleration, and quick braking. Although 

wheelchair basketball is not a contact sport, some incidental contact is inevitable, so spoke guards cover the 

rear wheel spokes to prevent damage. Spoke guards 

made of high-impact plastic provide several additional 

benefits. They allow players to pick the ball up from 

the floor by pushing it against the spoke guard and 

rolling it onto the lap, they protect hands and fingers 

from aggressive play when reaching for the ball, and 

they provide space to identify team affiliations and 

sponsor names. Stability comes from the camber in 

the wheels, which creates a broader wheelbase; it 

brings the top of the wheel closer to the body, making 

the wheelchair more responsive to turns, and protects 

a player’s hands during collision because hands are 

located away from the plane of contact. To gain an 

advantage for shooting baskets, forwards usually try 

to make wheelchair seats as high as possible within 

the 53-cm limit. Seats typically angle toward the rear, 

creating “squeeze” or seat bucketing of 0.085 radians 

to 0.255 radians (5°–15°) to increase the player’s pelvic 

stability. Guards prefer lower seat heights, which, combined with increased seat angle, makes chairs faster 

and more maneuverable for ball handling. Cushions 

may be used if made of flexible material the same size 

as the seat of the wheelchair and no higher than 10-cm 

thick, unless a player is classified as being restricted 

to a cushion that cannot exceed 5 cm. Because equipment can be used to create competitive advantage, it 

is carefully regulated. Equipment cannot completely 

equalize player performance, so modified rules and 

classification work to create functional equivalence 

between teams. These parameters work together to 
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Assistive Devices for Service Members With Disabilities

create a sport that is equal in challenge and excitement 

to stand-up basketball.

Wheelchair rugby differs from basketball in that 

players must have both an upper and lower extremity 

impairment to be eligible to participate. The object of 

wheelchair rugby is to cross the opponent’s goal line 

with two wheels while in possession of the ball. While 

the offensive team tries to advance the ball, the defense 

works to halt its progress with turnovers. Players 

tend to use extreme wheelchair configurations, elastic 

binders, foam arm protectors, and special tacky gloves 

to improve performance. As in basketball, players 

become extremely proficient in adapting their equipment to promote balance and speed, so much that they 

often appear to possess more functional capacity than 

their diagnoses would suggest. Wheelchair styles are 

strictly regulated to ensure fairness, but vary considerably depending on a player’s preferences, functional 

level, and role on the team. Rugby chairs have extreme 

amounts of camber (16°–20°), significant bucketing, 

and antitip bars. Camber provides lateral stability, 

hand protection, and ease in turning. Bucketing helps 

with trunk balance and ball protection.

Serious tennis players use special wheelchairs that 

are equipped with three wheels—two large for propulsion, and a single, 5-cm caster in the front under the 

feet that allows for quick turning. The large wheels are 

typically 61 cm to 66 cm (24–26 in.) in diameter and use 

high-pressure tires (8.4 k/cm–14.1 k/cm, or 120–200 

psi) to reduce rolling resistance on the court. Wheels 

are set with extreme camber to maximize mobility and 

stability on the court, especially when making shots. 

Players with high-level spinal cord injury play with 

power wheelchairs and with longer rackets to compensate for length taken up by strapping the racket 

to the hand.

The track and field sports have been adapted to 

disability since the Stoke Mandeville Games, and 

include throwing and racing events.44 The throwing 

events allow competitors to use specially designed 

throwing chairs attached to holding devices because 

they offer greater stability and support. Throwing 

chairs are taller and eliminate the large wheels that 

could potentially interfere with the dynamic upper 

body movements required in throwing events. When 

a wheelchair is used, the seat and cushion must not 

exceed 75 cm in height.45 The chair design is important 

because it can significantly enhance performance, depending on how well it matches the thrower’s body 

and functional abilities. Consequently, athletes select 

chairs of different configurations to optimize their 

throwing performance.

Wheelchair racers and others with physical impairments compete in events from short distance sprints 

through marathons. Wheelchairs used in racing are 

customized and designed to fit the body of each user. 

The design of a racing wheelchair optimizes the abilities of each user, incorporating features such as threewheeled design, use of high-pressure tubular tires, 

lightweight rims, precision hubs, carbon disc or spoked 

wheels, compensator steering, small push rings, ridged 

frame construction, and 2° to 15° of camber. The fit of 

the racing chair to one’s body and abilities is critical 

to overall performance.46 Racing chair manufacturers 

require many body measurements when a chair is ordered because the frame and seat cage are made to fit 

each individual.47 Individuals with upper transradial 

amputations may use cosmetic prosthetic hands that 

have been positioned into a fist or ball with a highfriction surface to simulate racing gloves.

Wheelchairs have also been redesigned for use in 

backcountry and wilderness. Athletic individuals with 

a desire to hike, camp, and go where conventional 

wheelchairs cannot have designed adaptations to 

make rough terrain navigable. They use 66-cm (26-

in.) knobby tires like those on mountain bikes to gain 

traction on soft, wet, or difficult terrain. Front casters 

are significantly larger to decrease the chance of getting stuck on obstacles. Larger casters require frame 

redesign, so an off-road wheelchair looks more like a 

four-wheel buggy than a typical wheelchair.

Cycling using adaptations to typical bicycles, tandem cycles, or hand cycles opens this recreational and 

competitive sport to individuals with many types of 

impairments. Using toe clips, altering the size of the arc 

of the pedals, or modifying the handlebars, handgrips, 

or placement of the gears and brake levers are the only 

modifications some need.48

For those with lower extremity impairment, such as 

spinal cord injury, multiple sclerosis, hemiplegia, and 

amputation, hand cycles substitute use of the upper 

extremities and provide the greater stability of three 

wheels and placement close to the ground.49 Cuffs can 

be mounted to the arm crank handles for those with 

reduced grip strength. Two types of hand cycle designs 

are typically used: upright and recumbent. In an upright hand cycle, the rider is in a vertical position, as in 

a wheelchair. Upright hand cycles use a pivot steer in 

which only the front wheel turns while the rear wheels 

of the cycle follow. 

It is easier to transfer into and balance an upright 

cycle. In the recumbent hand cycle, the rider’s torso 

is semireclined and the legs are positioned in front of 

the pelvis. Steering occurs in one of two ways. In one, 

as the rider leans toward the turn, force is transferred 

through a linkage bar, causing the frame to pivot and 

turn, which is challenging for riders without trunk 

stability. A pivot-steering, recumbent hand cycle uses 

the rider’s arms and shoulders to execute turns like a 

typical bike. Recumbent hand cycles are ideal for rac-
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Care of the Combat Amputee

ing because they are light and fast.50 Individuals with 

upper limb amputations require modifications to the 

pedal handle and to the terminal device to facilitate a 

firm interface that promotes pushing and pulling on 

the handle throughout the pedal cycle (over 360°).

Water sit skis can compensate for trunk instability and hand weakness and incorporate a variety of 

adaptive features to suit a wide range of functional 

levels. Some skis adjust vertically, horizontally, and 

diagonally at the fin, allowing users to fine-tune their 

equipment to meet various skiing styles, body weights, 

and boat velocities. At the competitive level, sit-skiing 

events include men’s and women’s slalom, tricks, and 

jumping.50

Adaptive ski equipment (eg, outriggers, monoskis, 

and biskis) emerged from analyzing the physics of skiing and applying mechanical concepts to compensate 

for a skier’s movement limitations. Veterans with limb 

loss learned stand-up methods that added outriggers. 

Originally, outriggers were made from the tips of 

outriggers from damaged skis mounted to the ends 

of forearm crutches. The Austrians used outriggers 

with the ski tips in a continuous running position, but 

flip-skis use a spring-loaded mechanism to allow the 

tip to either parallel the snow in running position or, 

when released, to flip up on the heel of the ski tip so 

outriggers can function more like poles or crutches. 

A claw bolted to the heel of the tip provides traction 

in icy lift lines. The monoski combines a fiberglass, 

form-fitting cab with a suspension mechanism attached to a single ski. A lever mechanism allows the 

skier to raise the height of the cab to the level of a 

chairlift. Once up, monoskiers can push forward in the 

lift line, using outriggers in pole position, and allow 

the chairlift and its momentum to scoop them up. To 

dismount, the skier leans forward as the lift reaches 

the dismount down slope, creating the momentum to 

drop off the lift.

In sled hockey, typical ice hockey rules apply, with 

some changes because of the nature of the game and its 

participants. The ice surface, goal net, and pucks are all 

the same as in stand-up hockey.51 The primary piece of 

equipment used in sled hockey is the sledge, a metalframed oval sled with two blades and a small runner; 

a seat with a backrest; leg straps; and optional push 

handles. A typical hockey stick is shortened to 73.6 cm 

(29 in.) and modified with two picks (metal pieces with 

a minimum of three teeth, measuring a maximum of 

4 mm) attached to the end.51 Picks provide traction 

to move the player down the ice and give the player 

leverage for shooting the puck with the blade end of 

the stick. With a quick flip of the wrist, players are able 

to propel themselves using the spikes, then play the 

puck with the blade end of the stick. Players generally 

use two sticks with blades to facilitate both propulsion 

and shooting with either hand. 

TRANSPORTATION

Transportation is a key component of full integration into the community. Accessible public transportation is necessary to provide persons with disabilities 

the same opportunities as others: employment, education, religious worship, and recreation. In the United 

States, the Individuals with Disabilities Education Act52 

and the Americans with Disabilities Act of 199053 have 

provided people with disabilities the opportunity to 

access schools and public transportation. The Americans with Disabilities Act transportation requirements 

mandate accessible fixed-route vehicles, as well as 

complementary paratransit services for those unable 

to use the fixed-route service. A subset of the disabled 

population is the wheelchair user, who may not be 

able to transfer to a vehicle seat and might, therefore, 

remain seated in a wheelchair. 

The wheelchair user should be afforded the same 

level of safety as passengers sitting in vehicle seats 

that meet federal safety standards. However, the 

wheelchair-seated passenger is usually at increased 

risk of injury in event of a vehicle collision or emergency maneuver. Currently, there are no federal safety 

standards for devices used to transport wheelchairseated passengers. However, there is a national and international effort to develop product safety standards 

for wheelchairs used as seats in motor vehicles. The 

standards establish the severity of vehicular crashes 

the wheelchair should withstand, as well as set the design criteria for securing the wheelchair in a vehicle.54,55 

They evaluate the complete wheelchair, frame, base, 

and seating system; however, seating systems are often 

added aftermarket. Wheelchairs using aftermarket 

seating systems are not likely to be tested to evaluate 

their ability to withstand crash forces, or they may 

invalidate some testing. Because the seating system 

directly interfaces with the user, it is critical that these 

systems do not fail during a vehicular crash.

Motor vehicle seats must be effectively anchored to 

the vehicle floor to ensure that their mass does not add 

to the restraint loads on the occupant. When an occupant remains seated in the wheelchair, the wheelchair 

becomes the vehicle seat. Aftermarket securement 

systems must be used to anchor a wheelchair to the 

vehicle floor. Again, due to the lack of federal safety 

standards for devices used to transport wheelchairseated passengers, national and international efforts 

strove to develop voluntary product safety standards 

for wheelchair tie-down and occupant restraint sys-
711

Assistive Devices for Service Members With Disabilities

tems. In the United States, the Society of Automotive 

Engineers’ Adaptive Devices Subcommittee developed 

SAE J2249: Wheelchair Tie-Downs and Occupant Restraint 

Systems for Use in Motor Vehicles.

55 Shortly after, an international standard was published.56 The most common 

securement system found in public transportation is 

the four-point tie-down system (Figure 26-12). This 

system consists of four tie-down straps that anchor to 

the vehicle floor and four points on a wheelchair (two 

front and two rear). The end fittings that attach to the 

wheelchair can be hooks or loops that wrap around 

the wheelchair frame. The main advantage of this type 

of system is that it can be used with a wide variety of 

wheelchairs and does not require special hardware to 

be added to the wheelchair. 

A second method of securement is an automatic 

docking system, which uses a wheelchair adaptor—

special hardware mounted on the wheelchair—to 

engage with a docking station or receptacle mounted 

to the vehicle floor or sidewall. The advantages of 

wheelchair docking technology have been seen with 

proprietary systems that have been used for independent securement of wheelchairs in private vans.

Driving Controls

Adaptive driving controls for an individual’s vehicle are prescribed after the individual completes 

a comprehensive driving evaluation and education 

and training program provided by a certified driving 

rehabilitation specialist. The evaluation assesses the 

individual’s basic skills necessary for driving, such as 

vision, perception, cognition, physical functioning, and 

knowledge of driving, and an on-road assessment that 

evaluates actual driving skills. After completing the 

program, the certified driving rehabilitation specialist 

and the individual can determine if the person will be 

able to drive with the recommended equipment.

Adaptive driving controls may include modified 

steering devices, accelerators, and a variety of secondary vehicle controls. A steering device, such as a spinner knob attached to the steering wheel, can allow for 

one-handed steering (Figure 26-13). A left-sided accelerator can be used if the individual’s right foot cannot 

operate the gas or brake pedals. A turn signal crossover, 

which relocates the turn signal indicator from the left 

side of the steering wheel to the right, can be used to 

allow individuals to access the turn signal using only 

the right hand if the left is impaired. Other secondary 

vehicle controls, such as windshield wipers, lights, and 

horns, can be relocated to provide timely and accurate 

access with the functional or dominant hand. 

Positioning straps (eg, chest harnesses), used in 

combination with the seatbelt, provide additional 

trunk control if sitting balance is compromised and 

interferes with functional operation of the vehicle. 

A strap or other modification for seatbelt retrieval is 

helpful if grasp or reach is limited. A parking brake 

extension allows access to floor-mounted parking or 

Figure 26-12. A four-point tie down system for wheelchair 

transportation.

Figure 26-13. A steering knob can aid in driving.
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Care of the Combat Amputee

emergency brake pedals. Mirrors may compensate for 

partial loss of visual fields or the presence of scotomas. 

As with all adaptive equipment, specialized education 

and training is required to assure correct placement 

and proper use of the additional mirrors.

Vehicle Access Technology

A variety of adaptive equipment and vehicle modifications can be used for vehicle ingress and egress. 

Automatic car door openers (ie, keyless entry), built-up 

key holders, or key turners are recommended if hand 

function is impaired. To ease the transfer for driver or 

passenger from the wheelchair into the vehicle seat, 

a power base seat can swivel out, glide out of the vehicle, and lower to a desired level. Portable wheelchair 

ramps are available to load and unload unoccupied 

mobility equipment, such as manual or power wheelchairs or scooters, into the vehicle without significant 

vehicle modifications (Figure 26-14). Car topper lifts 

attach to the top of a sedan and lift and store a manual 

wheelchair on top of the vehicle. Wheelchair or scooter 

users may require a vehicle ramp or lift to get into 

their vehicles or to lift their mobility devices into their 

Figure 26-14. A portable wheelchair ramp can be used to 

access vehicles.

vehicles. Before the recommendation and installation 

of any adaptive equipment in a vehicle, the individual, 

mechanical device, and vehicle compatibility should 

be verified. 

REHABILITATION ROBOTICS

Rehabilitation robotics can be categorized into three 

main categories: mobility aids, manipulation aids, and 

therapeutic robots. The use of robots in rehabilitation 

is quite different from industrial applications, where 

robots operate in structured environments with predefined tasks and are usually separated from human 

operators. Many tasks cannot be preprogrammed in 

rehabilitation robots, such as picking up a newspaper 

or opening a door. Although some evaluations and 

studies have looked at rehabilitation robots, the benefits and disadvantages of systems in service need to 

be further analyzed to better understand the users and 

their needs. Many individuals with disabilities can be 

satisfied with traditional mobility aids (eg, canes, walkers, manual wheelchairs, power wheelchairs, scooters). 

However, for some people with disabilities, it is difficult 

or impossible to use current mobility devices without 

assistance.58 Individuals with low vision, visual field 

neglect, spasticity, tremors, or cognitive deficits may 

benefit most from “intelligent” mobility aids that have 

evolved from mobile robots. People with these conditions often lack independent mobility and rely on a 

caregiver to provide mobility. Intelligent mobility aids 

often consist of either a wheelchair or walker, to which a 

computer and a collection of sensors have been added, 

or a mobile robot base to which a seat or handlebars 

have been attached. Intelligent mobility aids have been 

designed based on a variety of traditional mobility 

aids and provide users with navigation assistance (eg, 

assuring collision-free travel, aiding the performance 

of specific tasks, and autonomously transporting the 

user between locations). Smart wheelchairs are ideal 

devices to test novel input methods because, unlike 

standard wheelchairs, the interface can be implemented 

on their onboard computers. More importantly, smart 

wheelchairs can avoid obstacles, providing a safety 

net for input methods that are inaccurate or that have 

limited bandwidth. For example, voice control has 

proven difficult to implement on standard wheelchairs; 

however, obstacle avoidance capabilities built into control software may protect a user from the consequences 

of unrecognized (or misrecognized) voice commands 

and can “fill in” the small, rapid navigation commands 

that are much easier on a high-bandwidth input device, 

such as a joystick.

Robotic manipulation aids provide people with 

disablities tools to perform ADLs and vocational support tasks that would otherwise require assistance. 

Operators usually control manipulation aids with 

joysticks, keypads, their voices, or other input devices. 

Robotic manipulation aids can be classified into three 

groups: 

1. Task-specific devices: electromechanical devices used to perform simple tasks, such as 

powered feeders and page turners.
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Assistive Devices for Service Members With Disabilities

Augmentative and alternative communication 

(AAC) refers to any communication approach that 

supplements or replaces natural speech or writing. 

Effective communication is desired for individuals 

to be able to participate in work, school, leisure, and 

entertainment activities. Although a range of AAC 

interventions are possible to engineer solutions for 

improved function and participation, the demands 

of communication should be analyzed in terms of 

language requirements.

 AAC endeavors to optimize the communication 

of individuals with significant communication disorders.59 The basic elements of a comprehensive AAC 

assessment and the role of rehabilitation engineers in 

making decisions about AAC technology are critical 

to achieving successful outcomes. The significance 

of language issues and AAC language representation methods must be understood before evaluating 

solutions, emphasizing the need for AAC technology 

to support the spontaneous generation of language 

to optimize communication function and participation. Only by understanding the language issues can 

rehabilitation engineering professionals appreciate 

the technology, device features, and human factors 

associated with AAC interventions.

AAC interventions can be classified by the methods 

used to transmit messages (ie, aided or unaided).60 

Unaided symbols do not require an external device 

or apparatus; nothing other than an individual’s body 

parts are needed to transmit a message (eg, using 

one’s hands to gesture). Aided symbols, on the other 

hand, require an external device. Technology for aided 

AAC can be further classified into low, light, or high 

performance. High-performance technology solutions 

can then be delineated into nondedicated or dedicated 

AAC systems. Nondedicated technology generally refers to computers that are running AAC software, but 

the primary application of the technology is computer 

based. Conversely, dedicated AAC devices have been 

designed and evaluated specifically for communication, but frequently have secondary features that provide computer or environmental controls. The range 

2. Workstation robots: the robotic manipulator 

may be built into a workstation and can be 

used in a vocational environment.

3. Wheelchair robots: a manipulator arm 

mounted on the electric-powered wheelchair 

that augments mobility and manipulation, 

allowing the user to accomplish ADLs and 

vocational tasks. 

Both the interface between the user and the robot 

and the interface between the robot and the objects 

being manipulated affect the functionality of a robot 

manipulation aid. A robotís operation sophistication 

is limited because users are only able to exert so much 

control. The interface between the robot and the objects 

being manipulated is usually a simple pincer-like gripper; however, a large portion of activities performed 

in school, work, and daily living involve pick-andplace tasks that may be carried out with this simple 

end effector. 

AUGMENTATIVE AND ALTERNATIVE COMMUNICATION

of aided technology increases as the availability of 

power, voice output, electronics, and computer chips 

become part of the system.

Comprehensive Assessment

The AAC assessment may be the most important 

event in the life of an individual with a severe communication disorder that limits functional use of natural 

speech. For the beginning communicator, the AAC assessment process should establish AAC interventions 

to build communication competence to maximum 

potential across the individual’s life span. However, 

for an adult with a degenerative neurological disorder, 

an AAC assessment should consider the individual’s 

changing communication needs throughout the course 

of the disease. 

An AAC assessment improves an individual’s 

communicative functioning and participation in 

various activities and environments. The assessment 

is a client-centered, multidisciplinary team process.61,62 

Various AAC assessment models have been proposed 

that contain feature-match components, including the 

predictive assessment model63,64 and the participation 

model.65 With these AAC assessment models, data 

are collected and information is gathered to make 

intervention and management decisions.66 The three 

primary objectives of an AAC assessment are to 

determine functional communication needs, identify 

(match) interventions to increase or maintain interactive communication, and monitor or measure the 

effectiveness of intervention.65–67 The principles of 

evidence-based practice should be reflected in comprehensive AAC assessment.59,68

Language Representation

Three basic methods are used to represent language 

in AAC systems and are termed “AAC language representation methods” (LRMs). Evaluating the effectiveness 

of each method starts by considering the nature of a 

language. To be effective, AAC LRMs used with technol-
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Care of the Combat Amputee

COMPUTER ACCESS

Client-side AT helps disabled users access computers. Computer operating systems and applications 

coevolved with the mouse, and some software cannot 

be used without one. This is problematic because the 

operations that are most troublesome for individuals 

with physical disabilities are often those that involve 

button presses. However, pointing devices come in a 

variety of shapes and sizes. The most familiar pointing 

devices are the mouse and the trackpad (most often seen 

on laptop computers). Other frequently seen pointing 

devices include the trackball and the trackpoint. Pointing devices more commonly associated with individuals 

with disabilities include touch screens, head-mounted 

mouse emulators, and mouse keys. Each pointing device requires a different set of skills, which a clinician 

can match to an individual’s abilities. 

ogy need to have the characteristics of natural language, 

such as being generative, recursive, and polysemous, in 

order to achieve maximum performance. Rehabilitation 

engineers systematically evaluate the performance of 

various methods against the characteristics of natural 

language.

The three common LRMs are based on singlemeaning pictures or univocal pictures (intended to 

have only one meaning), semantic compaction or 

polysemous pictures (intended to have more than one 

meaning), and traditional orthography (the alphabet). 

Studies have shown that univocal LRMs, polysemous 

LRMs, and alphabetic LRMs have differential effects 

upon performance. 

Figure 26-15. The principle components of an electronic aid 

to daily living.

ELECTRONIC AIDS TO DAILY LIVING

Electronic aids to daily living (EADLs; also referred 

to as “environmental control units”) are specialized AT 

designed to enable individuals to operate household appliances and electronics if they cannot use the standard 

controls (eg, light switches, television, cable box, DVD 

player, stereo, heating and air conditioning, fans, doors, 

draperies or blinds, etc; Figure 26-15).

The user display and user control interface constitute 

the human–technology interface.69 The user control 

interface is the selection method used to control other 

AT (eg, direct selection, scanning, directed scanning, 

auditory scanning, voice recognition, and coded access). The user display is usually a visual feedback 

system that helps the individual operate the device; 

though auditory feedback systems can be used to help 

the visually impaired. The central processing unit is 

generally a microprocessor-based system designed to 

process input signals and direct output signals. The 

output signals may include infrared, radio, telephone, 

and electrical signals transmitted over house wiring (via 

an X-10 system). Typically, X-10 modules and receivers 

provide power control of household appliances (eg, 

lights, fans, etc). Additional control, such as channel 

changing and raising and lowering volume, requires 

infrared signals. 

The ideal assessment for an EADL would include 

the client, an occupational therapist, and a rehabilitation engineer, and the evaluation would be conducted 

in the client’s home. The occupational therapist can 

help establish the best user control interface, and the 

rehabilitation engineer can help choose the appropriate 

technology. The advantage of conducting the evaluation 

in the client’s home is that all the options can be explored 

in the environment in which the system will be used. 

Factors to consider when performing an evaluation 

for an EADL include:

	 •	 client’s goals (ie, what controls are desired?);

	 •	 client’s physical abilities and ability to use

a control interface;

	 •	 other AT the individual uses;
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Assistive Devices for Service Members With Disabilities

	 •	 client’s prognosis (ie, is the condition stable

or expected to get progressively worse?);

	 •	 client’s cognition;

	 •	 the system’s purpose (ie, for use in the home

or at work, in one room or throughout the 

house, etc);

	 •	 system reliability, flexibility, and ease of

operation;

	 •	 local technological support for installation,

configuration, service, and updates; and

	 •	 expense of the system and the funding

source.

Some EADLs are available commercially, either as 

stand-alone systems (ie, they only perform environmental control unit functions) or systems integrated 

with other AT. Voice-activated systems have recently 

made progress. Once a system is identified and purchased, it is important that it is properly set up and 

configured in the home, and that the client is provided 

proper training in its use. Setup, configuration, and client training should be provided by the vendor or local 

representative. In addition, a local vendor should be 

able to provide the client with follow-up service and 

support (Exhibit 26-1).

VETERANS WITH DISABILITIES AND RECREATIONAL SPORTS EQUIPMENT

Today, the number of sports and recreation opportunities for veterans with disabilities is seemingly 

endless, due in large part to advances in AT that compensate for impairments. The Veterans Health Administration (VHA) provides adaptive recreational and 

sports equipment. 

The Clinical Practice Recommendations for Issuance of Recreational and Sports Equipment, written by 

an interdisciplinary team with the Veterans Affairs 

Prosthetics Clinical Management Program, outlines 

the recommended approach for providing adaptive 

equipment to beneficiaries.70 According to the published recommendation, each veteran is entitled to an 

individualized assessment for adaptive recreation and 

sports equipment. The evaluation includes examining 

the veteran’s medical diagnosis, prognosis, functional 

abilities, and goals. The VHA defines “recreational 

leisure equipment” as any specialized equipment 

intended for recreational activity that does not inherently exhibit an athletic or physical rehabilitative nature. Examples include adaptive devices for hobbies 

and crafts or adaptive fishing or hunting devices. The 

VHA defines “recreational sports equipment” as any 

specialized equipment intended to be used in a physically active or competitive environment. Examples 

include sports wheelchairs, hand cycles, sit skis, and 

artificial limbs for recreational or sports applications. 

Powered devices for sport participation can potentially be provided to individuals whose activities are 

severely limited without their use when the individual 

meets general criteria for power mobility. An example 

of powered sports equipment is an EPW for powered 

wheelchair soccer. Recreation and sports technologies 

provided by the VHA must be adaptive in nature to 

specifically compensate for loss of or loss of use of a 

body part or body function. Standard nonadaptive 

equipment, such as skis, boats, and two-wheeled bicycles, are not provided by the VHA. 

Veterans and active duty service members enrolled 

for VHA care who have lost or lost use of a body part 

or function for which an adaptive recreation device is 

appropriate may be prescribed and provided equipment. Adaptive sports or recreation technology may be 

issued to veterans seeking to enhance or maintain their 

health and attain a higher rehabilitation goal through 

sports or recreation and who also meet eligibility 

criteria. In order to qualify for adaptive sports and 

recreation equipment, the veteran must have (among 

other criteria):

	 •	 medical clearance to perform the activity;

	 •	 completed education on appropriate activity

and equipment options;

	 •	 demonstrated commitment to the activity

through regular participation;

	 •	 the opportunity to participate in the activity

consistently (eg, must have regular access to 

snow for cross-country skiing);

	 •	 tried the appropriate equipment options configured for specific needs and abilities;

	 •	 selected a device that supports the veteran’s

sports and recreation goals; and

	 •	 demonstrated the ability to use, transport, and

store the equipment.

Accessories for adaptive equipment can also be 

provided when justified (eg, a car carrier to transport 

the device to a safe training area, indoor rollers for 

hand cycles or racing wheelchairs in areas with inclement weather). Seating interventions for postural 

support and skin protection or specific adaptations for limited hand function may also qualify. 

The Veterans Affairs Prosthetics and Sensory Aids 

Service covers repairs and service on sports and 

recreation equipment. A knowledgeable clinical 

professional (ie, a recreation therapist, rehabilitation engineer, kinesio-therapist, physical therapist, 

or occupational therapist) must be involved in 

the comprehensive athlete evaluation, equipment 

trials, selection and modification, and education 
716

Care of the Combat Amputee

EXHIBIT 26-1

CASE PRESENTATION 

While serving in a combat zone, a 26-year-old male US Army officer was injured by an improvised explosive device. 

As a result of the blast, the patient sustained multiple injuries, including a right transtibial amputation, right transradial 

amputation, and massive soft tissue wounds and defects to the right posterior thigh and gluteal region. After evacuation 

from the combat zone to the continental United States, the officer underwent a prolonged hospital course that included 

multiple surgical procedures to the right upper and lower extremities for amputation revisions, wound washouts, and 

split-thickness skin grafting to his soft-tissue defects; multiple wound and blood-borne infections with multidrug-resistant organisms; acute renal failure induced by antibiotic medications; malnutrition; and sacral skin breakdown.

Once medically stable, rehabilitation was initiated to address the soldier’s impaired functioning. Therapy initially 

focused on regaining independence with bed mobility and activities of daily living in the hospital bed, as well as a 

preprosthetic preparation. The patient quickly regained the ability to transfer from his bed to his hospital-provided 

manual transport wheelchair, and the importance of addressing his seating and mobility needs was immediately 

evident. While simultaneously being fitted for and training with his upper and lower extremity prostheses, the patient began wheelchair training. He consistently refused to use a power wheelchair, and he reported that he viewed 

a manual wheelchair as a tool to regain the strength and endurance that had been lost. 

By 6 weeks after his injury, the patient was functioning at a level suitable for discharge to outpatient rehabilitation. 

His rehabilitation, including upper and lower extremity prosthetic fitting and training, continued on an outpatient 

basis. A few weeks after discharge, the patient was seen in a seating and mobility clinic for a customized wheelchair 

prescription. The weeks spent in a hospital-provided wheelchair allowed him to develop preferences and experience regarding his seating and mobility needs. With input from the patient as well as the rehabilitation and seating 

teams, the patient was prescribed an ultralight, folding wheelchair with an air-filled, adjustable volume cushion; 

removable, adjustable height, desk-length arm rests; 18-inch seat-to-floor height; spoke wheels with a quick-release 

mechanism; aluminum handrims; and push handles. 

Because of right upper extremity amputation, the patient propels his wheelchair with his left arm and his left leg. 

After being successfully fitted with an upper extremity prosthesis, he was able to use his prosthesis to assist with 

wheelchair propulsion. His prosthetic device does not afford him the strength, agility, and coordination to grip, 

push, and release the handrim in a manner compatible with efficient wheelchair propulsion; however, he is able to 

create enough friction between his silicone prosthetic hand and the aluminum handrim to assist with propulsion. 

Even with this assistance, the patient chooses to propel with his left leg more than 90% of the time. A relatively low 

seat-to-floor height allows him to easily use his intact left lower extremity for propulsion.

The patient admits to having difficulties climbing hills in his wheelchair. He ascends hills with the wheelchair facing down the hill, locks the brakes for rest periods, and allows his wife or other companion to assist by pushing his 

wheelchair. He insists that he prefers to use these strategies rather than a powered wheelchair. 

The patient opted for a folding frame because of the relative ease with which he could fold and maneuver the chair 

into small spaces. With trials of rigid framed chairs, he found the process of removing the wheels while suspending 

the weight of the chair in the opposite arm cumbersome, given his amputation and the limitations of his prosthesis. 

Given his limited upper extremity strength and function, an ultralight wheelchair was necessary to ensure efficient 

propulsion and ease of transport (ie, placing it in a vehicle). 

The history of sacral skin breakdown, multiple wounds in the patient’s right posterior thigh and gluteal regions, 

and insensate regions at the sites of his skin grafts necessitated the use of a pressure-reducing, air-filled, adjustablevolume seat cushion. By 6 months after his injury, his sacral pressure ulcer had fully healed, but his right lower extremity soft tissue wounds and skin grafts still needed to be monitored, requiring him to continue using this cushion.

The patient prefers ambulation with a prosthetic device as his primary means of mobility. Because of the extensive 

and severe soft tissue wounds and skin defects in his residual right lower extremity, he has a limited tolerance for 

weight bearing in a prosthetic leg. In addition, his prosthetic components frequently require maintenance, resizing, 

and other adjustments. For these reasons, the patient realizes the need to have an efficient and reliable secondary 

mode of mobility, and his wheelchair fills this need effectively.
717

Assistive Devices for Service Members With Disabilities

and training. The clinician works closely with the 

athlete, other equipment experts, and coaches to 

support the long-term goals surrounding sports 

and recreation participation.

SUMMARY

AT has an important role in the rehabilitation, community reintegration, and vocational success of veterans with disabilities. Many veterans with major limb 

amputations use multiple forms of AT daily, including 

wheelchairs for mobility. In order to obtain maximal 

benefit and to minimize the risk of abandonment, a 

proper assessment by a qualified, multidisciplinary, 

veteran-centered rehabilitation team is necessary. 

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