Benefits of tilt in space for good pressure relief

Pressure ulcers remain a significant problem within health and social care organisations and cost the NHS £3.8 million every day. ¹  They result from localised injury to the skin and/or underlying tissue, and usually over a bony prominence as a result of pressure, often in combination with shear forces.² Many patients are at risk of pressure ulcer development; however the elderly, malnourished, those with acute illness, or those with reduced mobility or immobility are at an increased risk due to their inability to reposition themselves.^3,4   Both pressure magnitude and duration are thought to be key risk factors in the occurrence of pressure ulcers, thus exposing wheelchair-bound patients or patients who remain sat out in a chair for long periods, to a higher risk of developing pressure ulcers.²  These patients often end up sat out in chairs for long periods of time during the day and sometimes remain there during the night if they experience pain or an exacerbation of condition when lying in bed.  

When sat out in a chair, 75% of a patient’s body weight will be placed through just 8% of the patient’s body surface area.⁵  Therefore, due to a high magnitude of pressure pushing through a small surface area, this will increase the risk of high pressure building up quickly over a shorter period of time, exposing the vulnerable bony prominences of the lower trunk to the risk of severe pressure damage. This will include the ischial tuberosities, buttocks, sacrum, and upper thighs, which support the patient’s body weight when seated.⁶     

One method that is often used for the seated patient to reduce the pressure over the vulnerable bony prominences of the lower trunk, is to use a pressure reducing cushion alongside encouraging or assisting the patient to regularly offload pressure by repositioning. This often includes asking patients to lean from side to side, lean forward or backwards, or perform wheelchair push ups to relieve the pressure.²  However, although this can be effective for some patients, for those patients who are unable to perform this type of repositioning, a wheelchair or specialist seating chair that has a tilt-in-space function can be extremely beneficial to redistribution of pressures over the lower trunk.²   

A tilt-in-space function is when the entire chair tilts on its frame with angle of the patient’s hips knees and ankles remaining the same.  This ensures that a patient’s posture is unchanged but pressure from the ischial tuberosities is offloaded with pressure redistributing up the patient’s back, creating a safe position for many patients whilst reducing the potential for pressure ulcer development.⁷   It is well known that good postural management can also help to reduce the risk of pressure ulcer development by allowing for a good, even weight distribution along with reducing the risk of shear forces on the body.^8,9  Therefore, with good postural management being a benefit to using a tilt-in-space chair along with the benefits of pressure reduction, it is clear that a tilt-in-space chair can be of great benefit to certain patient groups who sit out for long periods of time or where repositioning may be difficult.  

The degree of angle is all important when it comes to the optimal position for pressure reduction in tilt-in-space chairs.  An angle of between 15^o and 30^o has been shown to be optimal for improving positioning, reduce sliding, and contributing to increased functional ability.  However, for optimal pressure reduction, the angle must be increased with the research suggesting that an angle of between 30^o and 45^o is best to achieve effective pressure reduction.⁸  

Some additional benefits to using tilt-in-space chairs include⁸:

• Assisting with reduced head and trunk control
• Reducing the risk of falls and sliding from chairs
• Assisting with corrective positioning for those with kyphotic postures
• Improve physiological processes
• Facilitate easier repositioning by individual/carer 
  

Back cushion options

Extra pillow options

Which Chairs from OSKA have a tilt in space function? 

• OSKA Regis
• OSKA Vertex
• OSKA Nimble
• OSKA Tune
• OSKA Oasis
• OSKA Tune Express
• OSKA Nurture Bariatric
• OSKA Nurture Express
• OSKA Hambledon
• OSKA Bentley

References

1. NHS Improvement (2018) Pressure Ulcers: revised definition and measurement. Summary and Recommendations. NHS Improvement, London. 2018.  Available online: NSTPP-summary-recommendations.pdf (england.nhs.uk). Accessed 9 June 2022
2. Zemp, R., Rhiner, J., Pluss, S., Togni, R., Plock, J.A., Taylor, W. R. (2018) Wheelchair Tilt-in -Space and Recline Functions: Influence on sitting interface pressure and ischial blood flow in an elderly population, Biomed Research International, 2019, 1-10.
3.  Fisher, A. R., Wells, G., & Harrison, M. B. (2004). Factors Associated with Pressure Ulcers in Adults in Acute Care Hospitals. Holistic Nursing Practice, 18(5), 242-253.
4. Lindgren, M., Unosson, M., Fredrikson, M., & Ek, A. (2004). Immobility – a major risk factor for development of pressure ulcers among adult hospitalized patients: A prospective study. Scandinavian Journal of Caring Sciences, 18(1), 57-64.
5. Trumble, H.C. (1930) The skin tolerances for pressure and pressure sores. Medical Journal of Australia, 2, pp. 724–726.
6. Stockton, L., Kryzstof, F., Gebhardt, B., Clark, M. (2009) Seating and pressure ulcers: Clinical Practice Guideline. Journal of Tissue Viability, 18, (4) pp. 98-108.
7. Seating Matters (2022) What is the difference between back angle recline and tilt in space, [Online] https://seatingmatters.com/learn/blog/what-is-the-difference-between-back-angle-recline-and-tilt-in-space. Accessed 3 January 2024.
8. Seating Matters (2022) Why do we use tilt in space? [Online] https://seatingmatters.com/gb-ie/learn/blog/why-do-we-use-tilt-in-space. Accessed 3 January 2024.
9. Dunstall, R. (2023) Posture and pressure are inextricably linked, [Online] https://www.careflex.co.uk/info-centre/blogs/posture-and-pressure-are-inextricably-linked/#:~:text=Postural%20management%20is%20a%20key%20part%20of%20pressure%20injury%20prevention.&text=Appropriate%20postural%20management%20and%20equal,of%20developing%20a%20pressure%20injury. Accessed 21 December 2023.