Frequently Asked Questions
Can you speak more on pelvic obliquity? We were taught in school that a pelvic obliquity is named for the low side of the pelvis, not the high side?
Thank you for bringing this up, as standards vary not only between countries, but within countries and regions for which side to use when naming pelvic obliquity.
It's fine to use the low or the high side, but it is critical to say whether you are using the low or high side. "Right side lower pelvic obliquity" and "left side higher pelvic obliquity" are both correct and allow clinicians to communicate effectively. Trouble comes when a prescriber uses the phrase (for example) "Right obliquity" without saying whether it's the high or low side.
I have requests for gel cushions. Can you comment on the heat and moisture factors using gel cushions in our hot and humid climate? Do fluid cushions get hot as well?
Even in rarely truly hot Britain, the heat and moisture levels at the skin surface are a recognized factor in skin integrity. These effects are all the more important to consider in an even warmer climate.
Would suggest you have a look at the two-part blog on microclimate here on the Education in Motion website. There are also some useful resources on Education in Motion with downloadable, printable resources that go into properties in more detail here.
Gel polymers feel cool initially but warm up to body temperature quickly and can be a little sweaty due to the plastic top layer, although toweling or thick air exchange-type covers (like 3D spacer) can help.
Fluid-type cushions (for example JAY 2, JAY Fusion, Ottobock Floam, Invacare Solution) are generally a little cooler but tend to warm up similarly. There is one significant exception to this in that one new fluid cushion has special technology to manage microclimate. Further details are in the links above.
Cushions with air-exchange covers, base material with channels for airflow can help allow moisture to evaporate, which can help with skin cooling.
What is seat rake?
Seat rake means the angle of the seat rails, also "fixed tilt" and sometimes in the U.S., "dump." If the front seat-to-floor height is much higher than the rear, there is a lot of rake/fixed tilt/dump. If the seat is level, there isn't any.
What is the difference between fluid and gel?
Gel is a polymer, often silicone-based, that has a consistency much like a firm gelatin and compresses slightly rather than displacing. Fluid flows from one place to another within its containing sac, so is better for immersion than gel. For a more thorough discussion and printable resource, check out "Material Selection in Cushions" here on Education in Motion.
You talked about comfort; could you speak to the role of stabilization also?
Yes, stabilization is key for performance and tolerance, and even a feeling of "comfort." Because of this, wheelchair use tolerance is sometimes a better measure of cushion efficacy. A very soft foam cushion may feel comfortable initially, but then harden over time or feel unstable, meaning that a client can't use it as long.
High level cushions often combine materials to achieve a balance of comfort and stability, for example by having a dense foam base with a soft top layer and then fluid under the pelvis, plus positioning inserts to stabilize. For more information, check out the "Cushion Design Principles" resource here on Education in Motion.