The history of rehab shower commode chairs is dark. Traditionally, commode seats have been so poorly designed that one has to wonder if the designers actually sat on their creations.

One of the biggest failings has been proper consideration of the size, shape and location of a commode chair’s aperture, or opening. The aperture’s placement, size and shape can have a tremendous impact on how well the commode chair functions and how safe and easy it is to use. Here are the three main considerations when evaluating shower commode chairs for users with complex needs.

1: Aperture Location. An aperture that is not optimally placed for client use can cause pressure injuries. A common example of this is when an aperture is too far forward: This subjects the user to higher pressure on their sacral/coccyx areas, which can cause pressure problems.

One example of addressing this issue comes from Raz Design, which created the Ischial & Pelvic Alignment System (IPAS). Exclusive to Raz, the IPAS helps reduce the possibility of pressure issues at key pressure points by providing up to 2” of fore/aft seat adjustment or 1” of lateral seat adjustment. This means that the aperture can be more optimally positioned for the client’s ischial tuberosities (ITs). This is especially important for clients who sit with a pelvic posterior rotation in order to achieve greater trunk support. This “slouched” posture is often assumed so the client can achieve greater trunk stability. The same scenario occurs for larger individuals.

“We have been asked many times why our seats cannot be rotated, like some of our competitors’,” said a Raz Design spokesperson. “The answer is clear: If the seat can be rotated, the aperture needs to be centered. If it’s centered, it’s either too far forward or too large. The rear edge of our apertures is typically 1.5” in front of the back posts.”

2: Aperture width. Creating ideal aperture widths is all about understanding human anatomy. Ideally, you want to “float” the ITs in the commode aperture while maximizing the seating area and minimizing average sitting pressures. But to do that efficiently, you need to know how the locations of ITs varies for different clients.

For instance, on average, men’s ITs are 4.5” to 5.5” apart. For women, the ITs are generally a little farther apart, which is why the apertures for custom seats are typically 6.5” wide.

Since bariatric users have the same IT width as non-bariatric users, the apertures on the heavy-duty seats should be about the same size as on the regular seats.

Raz Design’s aperture widths are based on anthropometric data regarding ITs.

3: Aperture shape. Commode apertures come in different shapes, with round apertures being common. But a Raz Design’s spokesperson explained, “We use a keyhole or teardrop shape to provide more seat support in front of the ITs. This also helps to stabilize the pelvis while still providing access from the front for hygiene care, etc.”

For clients with complex seating and mobility needs — as well as for their caregivers — a design element as seemingly simple as a commode chair’s aperture can impact seated pressure and weight distribution, as well as how easily the chair can be used by clients and caregivers. Considering apertures and other design elements is crucial to determining which commode chair is best for your client with complex needs.

This story is sponsored by Raz Design.