Choosing the Right Cushion

Subscribe | Advertise | About Us | Contact Us | Home

February 2002

By Ginger Walls, PT, MS, NCS, ATP

Choosing the Right Cushion

When selecting the most effective wheelchair cushion, different materials should be considered with the guidance of an experienced seating team.

he individual needs of clients provide the guidelines for choosing the optimal wheelchair cushions. The factors of consideration are: diagnosis, comfort, sensation, skin integrity and history of skin breakdown, positioning needs, functional and activity level, type of wheelchair used, client preferences, continence, compliance, cognition, and environment-of-use factors.

A cushion—the seating support surface—is only one component of the total seating system. The total seating system may also be composed of a back support, upper and lower extremity supports, lateral pelvic and/or trunk supports, and a headrest. The necessity for and complexity of all these seating system components are also indicated by client needs. All components of the seating system must work together to provide the optimal comfort, postural support, biomechanical alignment, skin protection, spasticity reduction, and maximal function.

Medicare Eligibility Criteria
Many different types of cushions are available for wheelchair users. Medicare definitions and coverage policy/eligibility criteria classify cushions into four basic types: a 1-inch cushion (EO962); a 2-inch cushion (EO963); a pressure equalization cushion (EO192); and a custom molded seat (K0108, miscellaneous). Clients must meet the medical necessity criteria for Medicare coverage for the wheelchair cushion they choose. Most other third-party payors follow the Medicare coverage criteria.

Most wheelchair users, even part-time users, are able to qualify for a 1- or 2-inch wheelchair cushion, and part-time wheelchair users benefit from the use of such a cushion to maximize comfort and positioning in the wheelchair. To qualify for a 1- or 2-inch cushion, the wheelchair user must sit in the wheelchair for at least 4 hours per day.

To qualify for a pressure equalization cushion, the patient must have a history of decubitus ulcers and/or be at risk for developing decubitus ulcers while sitting in the wheelchair. Additional qualification criteria for a pressure equalization cushion may also include:

the client is unable to independently relieve pressure when seated in the wheelchair due to lack of strength and overall physical condition and is at risk for skin breakdown
has absent sensation under the ischial tuberosities
has tone abnormalities that lead to skin breakdown due to sliding or extensor thrust
has a high degree of muscle atrophy and requires protection of pressure reduction to prevent skin breakdown
has age-related changes resulting in decreased tensile strength of the tissues, incontinence, or poor circulation, which increase the risk for skin breakdown
has orthopedic deformities that result in a higher peak pressure underneath the ischial tuberosities and is at increased risk for skin breakdown
is diabetic and requires pressure equalization underneath the ischial tuberosities to promote adequate blood circulation throughout the lower extremities while seated in the wheelchair
has a degenerative medical condition, which is associated with a high incidence of skin breakdown.

A client meets the criteria for a custom molded seat when aggressive positioning and support are required to accommodate for severe orthopedic deformities and/or spasticity. A custom molded seat is contoured to the individual’s body and provides maximal contact and support to meet positioning needs.

Types of Cushions
Typically, these four types of cushions use the properties of foam, gel, air, or combinations of these mediums to provide their positioning and/or pressure-relieving qualities. Trade-offs and advantages and disadvantages exist among all of them, including weight, comfort, maintenance required, cover materials available, temperature and pressure sensitivity, and durability.

Foam is typically lightweight and can be easily contoured or cut to provide excellent positioning. Various densities and qualities of foam are available, eg, softer or firmer or open or closed cell, to allow different types of foam to be used for either positioning or pressure relief. Most pressure-relieving foam cushions use multiple layers of various types of foam to accomplish both positioning and pressure-relief goals. Some types of foam are temperature sensitive and this needs to be considered depending on the client’s environment. Cushions that utilize air as a pressure-relieving medium also have the advantage of being lightweight. Sometimes air-filled cushions have a higher degree of maintenance or client compliance required to ensure that the cushion is appropriately inflated. The client’s ability and willingness to monitor optimal cushion inflation must be taken into account when choosing an air-filled cushion. Air cushions are pressure sensitive, which is a factor in air travel and in significant changes of altitude. Lightweight hybrid cushions that utilize both air and foam to attempt to maximize positioning and pressure relief offer another alternative for wheelchair users.

Gel is frequently used in combination with some type of foam to provide a pressure-relieving cushion that also has excellent positioning properties and options. Gel contours to users’ bodies, distributing their weight over a maximal surface area to reduce pressure. Gel cushions are typically heavier than air, foam, or foam-air cushions. Gel can also be somewhat temperature sensitive.

Pressure-relieving honeycomb is an additional option, which provides lightweight positioning with pressure reduction.

Seating Systems
Custom seating systems can be either linear/planar or contoured. Often clients who require a custom seating surface also require some type of custom back. A planar seating system, which is used more with pediatric than adult clients, uses removable positioning accessories, including abductor pommels, hip/thigh guides, and lateral supports. Linear/planar systems frequently allow for adaptation for client growth, as well as for client movement. Custom contoured seating systems are exactly contoured to match the individual’s body to maximize support surfaces for pressure relief and positioning. Custom contoured seating systems can be fabricated with vacuum mold systems or pour-in-place mold systems, or carved out of foam. When using a vacuum mold system, a negative impression of the client is created and then used to construct a custom fitted seat and/or back. The negative impression may be recorded digitally or by pouring a liquid foam or plaster mixture into the negative impression left by the client in the vacuum mold system. Both linear/planar seating systems and custom molded seating systems may use different foam, gel, air, and honeycomb mediums to provide positioning and pressure relief in key areas as needed by the individual.

Clients also maximize their chance of choosing the correct cushion by working with an experienced physical or occupational therapist and durable medical equipment vendor in a seating clinic. Therapists and vendors should have credentials and certification that demonstrate their experience and expertise in seating. The Rehabilitation Engineering and Assistive Technology Society of North America (RESNA) credentials of assistive technology provider or supplier (ATP or ATS) are important indications of quality. A certified therapist and vendor can offer their combined experience to that of the client’s to assist in making the optimal cushion choice. A directory of RESNA-certified ATPs and ATSs is available at www.resna.org.

The Medicare Consumer Fraud Pamphlet about Medicare and Home Medical Equipment, available at www.medicare.gov, provides some guidelines for consumers about how to recognize a good supplier of home medical equipment.

Following are tips for choosing a reliable supplier: has a reputable business standing in the community; delivers and sets up equipment and makes sure you understand how it works; is responsive to inquiries or complaints about the equipment or its use; makes sure the equipment is performing up to requirements and that you are not having problems with it; provides or arranges for service and maintenance to the equipment; honors all warranties; refers you to the appropriate Medicare carrier if you have questions; provides you with equipment that is clean and in good working condition; lets you return equipment that is substandard or unsuitable for use; does not offer to waive Medicare co-payments or deductibles, without first determining financial hardship (see Medicare handbook for more information); tells you about supplier standards to which it must conform; and is a member of local or national trade organizations.

Most qualified seating clinics should have some type of computerized pressure mapping device available. Pressure mapping can be performed with clients sitting on their present cushion to establish a baseline and then repeated on subsequent cushions to see which cushion and/or seating configuration offers the best pressure relief. This is especially important for clients who have a high risk for or current skin breakdown.

Case Study
The following complex case illustrates the aforementioned point. A 27-year-old male with cerebral palsy resulting in spastic quadriplegia was referred to an outpatient seating clinic. He presented with severe spasticity, upper and lower extremity contractures, and skin breakdown over the spinous processes of his lumbar spine, over his left ischial tuberosity, and on the bony prominences of both feet. He also had a significant pelvic obliquity and scoliosis, resulting in poor pelvis and trunk stability and sitting posture. His ability to swallow was also impaired—he required suctioning multiple times during the day—thus, he required proper positioning to prevent aspiration of his secretions. He had both a G-tube and a J-tube. He was 5 feet, 3 inches tall and weighed 89 pounds.

He was unable to perform functional volitional range of motion, and his movements were primarily spastic and involuntary. As a result, he was confined to a wheelchair for all of his mobility and activities of daily living.

His wheelchair and seating system were not meeting his needs and were contributing to his current skin breakdown in the following ways: the wheelchair was poorly sized; it did not provide sufficient proximal lower extremity support; it did not at all contain or support his feet or distal lower extremities; it did not adequately accommodate to his scoliosis or pelvic obliquity; and did not adequately offer head support or positioning. His head would become entrapped between the top of his wheelchair and the bottom of his headrest, which provided a significant risk of injury.

He required a manual tilt-in-space wheelchair, a custom vacuum-molded multi-density foam seat and back with gel inserts, a headrest, a custom footbox, a four-point anterior pelvic positioning strap and a chest harness, and an anterior upper extremity support to provide him with essential postural support, prevention of skin breakdown and aspiration, prevention of further deformity, and safe comfortable positioning in his wheelchair seating system. Detachable armrests were required for transfers. Adjustable height armrests and anterior upper extremity support were required to provide upper extremity support not provided by conventional armrests. Flat-free insert tires were required to prevent flat tires and reduce maintenance because he was unable to perform this function. A manual tilt system was required to allow performance of pressure reliefs by the caregiver, to prevent skin breakdown, to assist with proper positioning, to allow performance of activities of daily living in the wheelchair, and to assist in the prevention of aspiration.

Wheelchair users have a wide variety of cushion types and materials to choose from. A knowledgeable and experienced seating team is best able to provide clients with the guidance necessary to meet their needs—from the simple to the most complex.

Ginger Walls, PT, MS, NCS, ATP, is clinic manager for the National Rehabilitation Hospital (NRH)/Regional Rehab, Washington, DC, and neuro program specialist for the NRH/Regional Rehab Outpatient Network. She is also chair of the Spinal Cord Special Interest Group of the Neurology Section of the APTA.

LOOKING FOR EXPERT ADVICE?

Experts here are available to answer all your questions!

Please contact us for more information about this feature, or to become an expert.

MEDIA CENTER

Interactive Media

Resources

	Classifieds
	Calendar
	Consumer Resources
	Media Kit
	Advertiser Index EAB Reprints Submit an Article

Featured Jobs

Audiologist Professional Growth and Entrepreneurial Opportunity Available
Park Ridge, Illinois

Clinical Education Coordinator School of Respiratory Therapy
Marquette, Michigan

Hospitalist Chestertown Chester River Hospital
Chestertown, Maryland

More Jobs...

Find a Job

www.thejobcure.com

ADDITIONAL ONLINE RESOURCES

Allied Healthcare		Medical Education
24X7mag Chiropractic Products Magazine Clinical Lab Products (CLP) Orthodontic Products The Hearing Industry Resource HME Today Rehab Management	Physical Therapy Products Plastic Surgery Products Imaging Economics Medical Imaging RT Magazine Sleep Review	SynerMed Communications IMED Communications
		Practice Growth
		Practice Builders

Become a featured employer

Featured Employer

KMart

Our Pharmacists know they make a difference!

Kmart believes in letting it's pharmacists do the job they were trained for; counseling and improving the health care of their patients.

View All Jobs

February 2002