Proper Wheelchair Positioning Improves Posture

June 29, 2023
Sit Straight infographic

Download a printable poster here.

Traditional wheelchair cushions used on uneven or sagging wheelchair seats can often buckle or tilt. As a result, cushions lose their intended effect and cause weakened or frail residents to slide forward or slouch.

Poor posture due to an unstable seating surface can produce dangerous shear forces, leaving residents susceptible to pressure injuries. These injuries can limit their sitting tolerance and ability to participate fully in functional tasks.

The Dangers of Sacral Sitting

Weakened, frail, or immobile wheelchair users often do not have the physical ability to sit properly in their chairs. The wheelchair may offer insufficient support from hammocking sling seats or be oversized for the resident. These issues can cause the pelvis to rest in a neutral or posterior pelvic tilt. After a short time, the user's buttocks slide forward on the seat, resulting in sacral sitting.  

Sacral sitting in a wheelchair is a dangerous position. It places contact pressure on the sacrum and ischial region and can lead to skin breakdown, falls from the wheelchair, poor sitting tolerance, and loss of functional abilities. 

Proper Wheelchair Positioning Starts with a Stable Base 

Most positioning or therapeutic cushions require a flat seating surface for optimal function and comfort. A supportive and level base is a key component in helping reverse poor posture and the dangers of sacral sitting, reducing the risk of pressure injuries.

But a level base alone doesn’t solve seating problems.

Adding a wedge-shaped cushion top can help limit forward sliding. The wedge shape keeps the hips positioned slightly lower than the knees, promoting an anterior pelvic tilt and subsequent upright sitting posture. This minimizes the effects of sacral sitting by decreasing pressure on the sacrum and coccyx while allowing the resident to achieve a proper postural position and improved sitting tolerance. 

Sit-Straight™ Wheelchair Cushions

Sit-Straight Cushions are a simple, effective, all-in-one positioning solution that combines a stable seating surface with a wedge-shaped cushion.

Sit-Straight’s convex base design counteracts the negative effects of a sagging sling seat. It fills the sagging area without modifying the wheelchair or raising the surface’s height. The wedge top limits forward sliding and maintains hips at 90° for optimal postural support. This allows residents to participate more fully in self-feeding, self-care, and recreational activities. 

Sit-Straight Cushions are also beneficial for caregivers as it frees them from continuously repositioning residents or using restraints to keep them from falling out of wheelchairs. See our printable poster for more on how Sit-Straight Wheelchair Cushions work.

AliMed offers a full line of Sit-Straight Wheelchair Cushions to meet the unique positioning needs of your residents:


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