• The user must be properly assessed in order to
have the correct seat size for good posture, stability and comfort.
• The best situation is for the user to fit the seat comfortably:
if the fit is too snug, pressure sores can develop, while too wide a
seat will encourage poor posture. A seat that is not deep enough will
force too much weight onto the user's buttocks, instead of distributing
it through the length of the thighs. Too deep, and the user may not
obtain the intended support from the backrest, as well as perhaps developing
pressure points behind the knees.
• Sagging seats are always a problem, as they
make the user's legs roll together, causing discomfort, and possibly
leading to pressure sores. Some wheelchairs have a facility to tighten
the seat canvas, otherwise a firm crescent-shaped cushion can counteract
the sag.
• Lightness of weight is an important consideration
as it is almost always an advantage for both the active user and carer.
• If the user can't sit upright unaided, a specialist
seating system may be required, rather than the standard wheelchair
seat. It is important to get a proper assessment for this.