Introduction: Most patients with spinal cord injury use a wheelchair as their primary means of mobility. When sitting, the pressure still represents the main and most important reason for pressure ulcers formation and low quality of life. By using the tilt in space and/ or back recline functions and wheelchair cushions, the pressure can be reduced when sitting and thus the risk of tissue collapse. Purpose: The aim of literature review was to investigate the effect of tilt in space and/or back recline functions and wheelchair cushions on pressure relief and blood flow in patients with spinal cord injury and healthy people. Methods: The literature review was conducted by obtaining articles in databases PubMed (MEDLINE) and CINAHL. Results: 19 studies were included in the review. In nine studies the effects of tilt in space and/ or back recline functions, and in seven studies the effects of wheelchair cushions were investigated. All three variables were investigated in three studies. The reduction of pressure was achieved by 20° of tilt and 120° recline from the horizontal plane in posterior direction. Increase in tilt angles had no effect on pressure at the sacrum area. Increase in skin perfusion was achieved by 15° of tilt and increase in muscle perfusion by 25 or 35°of tilt in combination with 120° recline. Three minutes long unloading session was more affective in increasing blood flow than one minute. Air cushions were more effective at pressure relief, pressure redistribution and were more efficient in decrease of adverse effects of sitting posture on pressure distribution. Conclusion: The first significant reduction in pressure is achieved by 20° of tilt. At 35° of tilt the maximum mean pressure gets closer to 60 mmHg which is frequently used as a threshold for tissue damage. 15° of tilt enhances skin perfusion over ischial tuberosity. Air cushions are most effective to relief pressure but the values of maximum mean pressure in upright seating position still exceeds 60 mmHg.
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