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It is a common question that people ask “What is the best manual wheelchair?”. This question cannot be answered since there is no “best” wheelchair. “Best” is relative to the person and their environment. For example, a pushrim road racing wheelchair is much different than a tennis wheelchair, which is different from a WCMX wheelchair. Yet, all are the optimum wheelchairs for their respective purposes.
But there is a worst wheelchair. That is the traditional hospital wheelchair (HWC). The HWC is the worst wheelchair for self-propelling in all environments, road racing, tennis, WCMX, rough terrain, smooth terrain, sidewalks, ascending hills, descending hills. I know of no other wheelchair design that is as all around ineffective, difficult, and in certain situations, dangerous to self-propel.
Understanding what makes a hospital wheelchair so cumbersome to self-propel is the key to understanding effective wheelchair design and push mechanics.
1. The armrests of the HWC blocks the user from having full access to their wheels. The user has to awkwardly reach over the armrests and then grab the wheels.
Takeway: Design sideguards/armrests that allow for direct and natural arm position access to the wheels.
2. The rear wheels of the HWC are positioned too far to allow the user to effectively access the wheels when leaning forward. This has the effect of shorting the power stroke and prevent the generation of torque when leaning forward on inclines or on high resistance terrain.
Takeaway: Design to enable wheels to move forward to allow for full access when the user leaning forward.
3. The rear wheel position puts the Center of Gravity (COG) too far to the front which inhibits the ability to unweight the front casters of the wheelchair when going over obstacles. Thereby, increasing rolling resistance and collisions with terrain obstructions such as cracks, roots, etc.
Takeway: Design to position the rear wheels under the users Center of Gravity as appropriate for the user.
4. Having the Center of Gravity forward of the axle also causes the wheelchair to excessively turn down the hill on side slopes. The only way to counter this effect is for the user to push with the downhill wheel while pushing less or braking with the uphill wheel.
Takeaway: Position the rear wheels under the user’s Center of Gravity as noted previously.
5. Due to angular momentum, it is more difficult to execute wheelchair maneuvers such as turns/spins when the COG is not centered over the axle.
Takeaway: Position the rear wheels under the user’s Center of Gravity as noted previously.
6. The high back and push handles of the HWC interfere with the user being able to employ their back muscles fully for pushing.
Takeway: Design to allow for adjustable back height and remove/reposition push handles to provide user full access to the rear wheels when the user’s elbows are extended backwards.
7. The excessive width of the standard HWC causes the user to overextend their arms from their body when pushing. This position creates muscular strain and reduces power.
Takeway: Design wheelchair width to allow for positioning rear wheels close enough to the user’s hips to enable for natural arm position access.
8. The forward and splayed position of the HWC two leg/footrests provides minimal stability for the user’s lower body and pelvic position creating an unstable base for pushing.
Takeway – Design to position feet and legs together on a stable platform to generate a solid base for upper body pushing.
9. The position of the parking brakes obstructs a full power push stroke while leaning forward.
Takeaway: Design to position (or remove) brakes to allow for full access to the wheel while pushing while forward leaning.
10. The excessive weight of the HWC creates more rolling resistance, particularly on inclines.
Takeway: Use a design and materials that enables the wheelchair to be as light as possible.
11. The rear wheels of the HWC are narrow, solid, and have no tread which causes the wheels to sink on soft surfaces and slip.
Takeaway – Use tires with appropriate tread and width for the environment as established by existing bicycling terrain protocols.
12. The folding aspect of the HWC frame creates a lack of rigidity that reduces the efficiency of push strokes as energy is diverted into making the frame sway rather than moving forward.
Takeway: Design a frame that provides sufficient rigidity for effective pushing.
13. Lack of Seat Dump: For users with less/little/no trunk stability, no Seat Dump decreases upper body stability.
Takeway: Design to allow for Seat Dump as required by the user to enable stability for pushing.
14. The Sagging Seat and Backrest of the HWC encourage the user to sit in a slumped position with shoulders rounded, head forward, with anterior pelvis tilt. This body position creates poor posture and mechanics for pushing.
Takeaway: Use seat materials that provide for a supportive and upright posture to enable effective pushing.
15. The large front casters of the HWC tend to flutter when pushing creating more rolling resistance and unpleasant frame vibrations.
Takeway: Use quality (smaller) front casters or a trike wheel that are designed to reduce/eliminate caster flutter.
From the standpoint of user propulsion and independence. There is no worse wheelchair than the traditional hospital style wheelchair. On a worldwide basis (which includes developing countries), this wheelchair is also the most commonly used wheelchair in existence. On a global scale, most people who use a wheelchair, use a HWC.
In my opinion, the reason for the widespread use comes to down simple economics and will be explored in greater detail in Part II. But the short answer is easy. The HWC is not only the worst wheelchair in the world, it is also the cheapest wheelchair in the world to manufacturer.
The HWC has the distinction of being (1) the most difficult manual wheelchair in the world to independently operate and self-propel, and (2) the most commonly used manual wheelchair in the world, and (3) the most inexpensive manual wheelchair in the world to manufacture. In my opinion, (1) and (2) are a direct result of (3).
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