Wheelchairs: Comparisons, Considerations, and Justifications
Mark Felling, May 2004
The following is drawn from 12 months of comprehensive research, firsthand testing, detailed observation, and personal interviews with users of more than 18 brands and 15 models of power wheelchairs by Mark Felling.
Manufacturers / Brands Considered
Redman Power Chair
Easy Care Products
Models Personally Tested
The power wheelchairs tested include multiple lines from all the major manufacturers and are representative of the full spectrum of features offered. Let's begin by examining the features common to all wheelchairs.
Features / Types Test Comments, Conclusions, & Preferences
Front Wheel, Mid Wheel, Center Wheel, Rear Wheel, 4x4, and Track Drives
I preferred mid or center wheel drive systems for one excellent, intuitive maneuverability, while not forfeiting forward speed or outdoor terrain navigability. Front wheel drives are usually slightly more limited in their forward speed and feel as though they have a "tail-wagging" symptom though with time users become comfortable with it and front wheel drives seem to be able to handle difficult outdoor terrain easier than a rear or mid/center wheel chair. Rear wheel drive chairs have excellent torque, forward speed, and range however they are less maneuverable tight spaces and their front casters can become bogged down in more difficult outdoor terrain. 4x4 and track drive chairs are designed purely for the outdoor enthusiast and to go where other chairs could not hope to wheel.
While seat height may be less of a factor for a smaller person, it is extensively important for anyone of a taller stature. It will determine whether the individual is literally able to "fit" into the community and their world. It will limit if they are able to sit at tables in restaurants, fit under accessible sinks, or otherwise utilize public resources such as taxi transportation. It will most likely determine the type of motor vehicles they are able to utilize and even if they are able to drive from the chair at all.
Length, Width, Weight, and Capacity
All are very important features that affect maneuverability and access to tight places in the community. Basically, they define the limits the wheelchair user will run into while living life. Weight affects the type of equipment such as lifts that can be utilized and capacity limits the users that can be carried.
Almost all power wheelchairs come with an integral controller from Penny & Giles, Invacare's Dynamic Mobility, or Quickie's Qtronix. There are a few other custom or otherwise unique controllers offered, however they are very rare and I only encountered one, that being found on the Lifestand. See the Lifestand discussion below for more details.
Penny and Giles is the only controller manufacturers not also associated directly with a wheelchair manufacturer. This has resulted in their application across many different brands of wheelchairs around the world resulting in excellent reliability and a wide variety of features.
Qtronix controllers have the smallest apparent market share of the three major offerings. They look very similar to the Penny & Giles controllers but are much less programmable, have fewer features, and seem to have a very "jumpy" feel to them that cannot be programmed out. Since I received few comments regarding their reliability positive or negative, I will assume they are fairly reliable. Since maneuverability and control ability are important to me, I consequently do not particularly like operating a chair with a Qtronix controller mounted.
Invacare acquired Dynamic Mobility out of New Zealand to act as the company's controller and electronics group. They also market their products to third-party manufacturers though with less success than Penny & Giles due to their affiliation with Invacare. Their MarkIV controllers are very robust while the MarkV controllers are highly programmable and feature intensive. All have very nice drivability characteristics; and dynamicoffers the widest array options and configurations on the market. Of note, Dynamic Mobility's controllers and electronics have a historical reputation for questionable reliability, though this seems to have been resolved in recent years with Invacare's additional funding.
Tilt in Space
Important for weight shifting, maintenance of balance, and upper body/neck strain relief in higher-level spinal cord injuries.
Assists in cathing, dressing, transfers, etc. Utilized for comfort to rest and relax for individuals confined to the wheelchair from the time they rise in the morning until the time they retire to bed in the evening.
Helps alleviate swelling in the feet and increase circulation. Helpful to raise feet up over table legs and other obstructions such as the initial bump of a curb cut or ramp.
Assists in reaching higher objects or getting under lower tables and desks. Indispensable for transfers when one finds themselves outside of their normal established environment, such as beds or vehicles when traveling. Socially desirable in that it gets the seated user closer to eye level and feeling less looked down upon.
There is extensive scientific research documenting the far-reaching positive health effects standing has on the human body. Dr. Shields at the University of Iowa, Des Moines is currently conducting a study that will demonstrate how the exercise through the process of standing up repeatedly throughout the day is much more beneficial than the more simplistic static standing achieved in a standing frame often for a few periods of time throughout the week. The complete results have yet to be published, however the results are expected to strongly emphasize the medical benefits of repeatedly standing throughout the day. Dr. Speigal at the University of Georgia Tech is in the earlier stages of a similar project.
The human body is genetically designed to operate and function within our world in a vertical orientation. Bowel and blatter functions are improved resulting in less complications, infections, and medications. Standing is the best form of weight shifting giving almost complete relief to required areas, reducing skin breakdown and subsequent costly hospitalizations, treatments, or even surgeries. Osteoporosis and other complications of bone weakening can be virtually eliminated. Breathing improves, respiratory and cardial efficiencies increase, circulation to the lower extremities intensifies and swelling to the legs and feet is reduced. Range of motion is better maintained, muscle density and form are increased, and muscle spasticity is often greatly reduced, again resulting in less medications, potential avoidance of a costly baclofin pump surgery and checkups, less skin breakdown on the heels, reduced edema, and greater overall comfort. The health benefits by themselves easily justify the slight additional cost of this feature, which over the long run will most likely pay for itself many times over.
The positive social and consequential mental-health effects on a wheelchair-bound individual can be even more life impacting than the many health benefits. Consider how much people complain about feeling looked down upon when they are slightly shorter than the average of the population, or not being able to see at a concert, political rally, or child's graduation. Imagine not being able to stand at the alter at your own wedding, not been able to see the food on display at the grocery store or in the buffet line, or view/read the items in a display case in a museum or your favorite store. Finally, think back to all the times you have stood in a circle discussing the latest gossip with friends and family after church, at a party, company outing, chance encounter, or family reunion picnic. Next time, try approaching a group of three or more and carrying on a conversation with them while on your knees.
Vocational goals and success may be more easily achieved simply through subconscious societal perceptions and acceptance. Meeting a new client, a speech, or a sales/training presentation are all expected to occur standing up. Inspecting a manufacturing line, looking over a machine or automobile engine, or even reading a display may require the height and proximity only standing can provide. Most of the world is designed around a seated position or a typical expected eye level of 4 1/2 to 5 1/2 feet. Subtle societal perceptions change very slowly so disabled individuals must adapt to our environment as best we can, since we have plenty of other hurdles to battle.
All of these features, in making the user healthier, happier, more employable, and more independent have the potential to exponentially benefit society as a whole through both quantifiable fiscal measures and less obvious qualifiable factors.
Many other qualities were also tested and considered such as drivability, traction, ride, comfort, power, range, durability, serviceability, looks, and user comments. However, these types of qualities are more specific to an individual wheelchair model and consequently must be discussed on a model by model basis.
Specific Model Discussions
Benefits of Standing: Physical Benefits
(taken from Fena designs web site at: http://www.vertran.com/stand.html)
Physicians & Therapists recommend standing for many reasons:
Normalizing of kidney and bladder functions
Improving digestive and bowel function
Maintenance of bone density
Improving flexibility and decreasing spasticity
Immobilization, or continuous sitting, creates pressure that can lead to obstructed blood flow and breakdown of the skin tissue. The resulting wounds are often decubitus ulcers, otherwise known as pressure sores. According to Thomas P. Stewart, P.h.D., a method for prevention and treatment for decubitus ulcers is to relieve pressure through postural changes. He maintains that passive standing can relieve pressure by shifting weight to the legs.
Immobilization in the sitting position often results in calcium deposits in the urinary tract. In many spinal cord injury cases, control of the bladder is often not possible creating additional problems in the urinary tract. According to a study conducted by James Walter, Ph.D. and Robert Dunn, Ph.D. at the Rehabilitation Research and Development Center of Hines V.A., standing device users experience more complete emptying of the bladder and report a significant decrease in bladder infections. The Journal of Physiology reports that increased pressure on the bladder in the standing position can result in better drainage. Thereby, minimizing urinary tract problems.
As outlined in the Handbook of Physical Medicine and Rehabilitation, wheelchair users often experience digestive complications as a result of prolonged immobilization. These complications include constipation, fecal impaction, and other dysfunction. Research by James Walter, Ph.D. and Robert Dunn, Ph.D. finds that frequent standing induces more regular bowel movements.
It has been well documented that continuous sitting inhibits weight bearing, which causes weakening of the bones and ultimately, osteoporosis. According to the Journal of Applied Physiology, passive standing can reverse the loss of bone density. Kaplan reinforces this finding, reporting that standing in spinal cord injury patients can reduce bone density loss and even build calcium in the bones.
Continuous sitting often causes tightening or shortening of the leg muscles. As a result, joints lose flexibility and contractures in the knees, ankles and hip joints can form. Spasticity is a muscular problem often found in spinal cord injury cases and other neurological disorders. A report by James Walter, P.h.D. and Robert B. Dunn, P.h.D finds that use of standing devices increases flexibility and decreases spasticity in the legs.
Continuous sitting contributes to poor blood circulation, which can result in pooling of blood in the lower extremities. The result is often fatigue, nausea, and dizziness. Thomas P. Stewart, P.h.D. reports in his research of passive standing that low blood pressure can be improved by repeated standing.
In the supine, or sitting, position a person cannot contract muscles for maximum inhaling and exhaling, which can lead to reduced respiratory efficiency and impairment such as pneumonia. It is widely believed that the standing position can induce better breathing. In a study by the American Physical Therapy Association, more than one third of the respondents reported better breathing after prolonged standing.
*For a copy of research papers on the benefits of standing, please contact FENA Design at 1-866-740-3362.
Benefits of Standing : Emotional & Social Benefits
The emotional and social benefits of using VERTRAN are far reaching.
Getting eye-to-eye with family, friends and business associates is easier when standing and mobile in VERTRAN.
Standing in VERTRAN promotes an overall feeling of better health.
VERTRAN increases self-assurance through greater independence in activities of daily life.
VERTRAN offers the freedom to stand at will and travel in any position between seated and standing.
VERTRAN opens doors to new employment opportunities by reducing barriers in the work environment.
VERTRAN users have participated in activities that they have not enjoyed in years including working, grocery shopping, cooking, pumping their own gas, using an ATM, attending sports events with full viewing, just to name a few!
For user comments with video see: