Postural stability refers to the continuous process of postural changes during sitting. The capacity to maintain postural stability in a sitting position is a prerequisite to performing activities of daily living (ADLs) and reducing the risk of shoulder injury, but also social functioning, satisfaction with the equipment, and thus quality of life.
Deficits in postural stability can severely limit performance in these aspects of life. [Dean, 1997; Riley, 1995; Dyson-Hudson, 2004; Trefler, 2004]
There are several contributing factors to obtaining and retaining postural stability in a sitting
position, namely trunk strength, large base of support, anterior pelvic tilt, thigh support and
back support. Anterior pelvic tilt and thigh support can both be achieved using an appropriate
Several studies have been aimed at examining the influence of seat cushions on postural stability in sitting. These studies used interconnected air cell cushions, contoured foam cushions, and flat foam cushions, and one study also used compartmented air cell cushions: the Vicair Adjuster O2 and the Vicair Vector O2. [Assaoui, 2001; Vreede, 2018 (master dissterdation); Springle, 2003].
Both Vicair cushions allowed participants to reach significantly further on seated functional reach tests compared to the other cushions that were examined, which is indicative of increase of postural stability.
Postural stability is an important factor for independence and social functioning, which leads to an increase of the quality of life experienced by wheelchair users. Furthermore, the role of trunk control of shoulder injuries may be an important consideration in mitigating injury and improvement of wheelchair propulsion.
Therefore, the selection of an adequate wheelchair cushion is of utmost importance to ensure a satisfactory quality of life for wheelchair users. An increase of postural stability in a sitting position can be obtained by using a compartmented air cell cushion (Vicair, Wormer, The Netherlands).