Choosing an optimal headrest for preventing postoperative alopecia - A manikin study

BACKGROUND

Postoperative alopecia is a rare complication after surgery. The etiology is thought to be pressure-induced hair follicles ischemia caused by prolonged immobilized head. Headrest is always used as head positioner during operation. The contact pressure between the head and headrest is believed to be related to the development of postoperative alopecia. The aim of this study was to find a headrest with the minimum contact pressure.

METHODS

Five different materials headrests - folded sheet, foam donut, gel donut, natural latex, and memory foam were examined. The contact pressures between the manikin's head and tested headrests were continuously recorded for 4 h using CONFORMat System sensor. The average and peak pressures over the contact area were measured at 15 min, 30 min, 45 min, 1 h, 2 h, 3 h, and 4 h. A generalized estimating equations (GEEs) analysis and one way repeated measures ANOVA were used to assess the data.

RESULTS

The memory foam headrest showed the lowest average and peak contact pressures over the contact area (p < 0.05), and the natural latex headrest, gel donut headrest, foam donut headrest, and folded sheet headrest revealed increase of the contact pressures in order. The peak contact pressure of the gel donut headrest at 4 h was significantly higher than that of at 15 min (p = 0.032) and 30 min (p = 0.037).

CONCLUSION

Of the five headrests we examined, the memory foam headrest is suggested to be the best choice for surgical patients because of its lowest contact pressure.

Neck posture and muscle activity in a reclined business class aircraft seat watching IFE with and without head support

The purpose of this study is to research if a headrest benefits the comfort of the passenger and lowers muscle activity in the neck when sitting in a reclined (slouched) posture while watching in flight entertainment (IFE) in an aircraft business class seat. No significant differences in muscle activity in the musculus sternocleidomastoid and musculus trapezius pars descendant were found between the conditions with headrest and without headrest. A significant difference in expected comfort rating was found. Subjects indicated they expect to experience more comfort with a headrest when watching IFE for a duration of two movies during a long-haul flight. This study also found a significant difference in posture. In the condition without headrest the head was more upright compared to the condition with headrest. The lack of significant difference in muscle activity and the significant difference in posture may indicate that humans tend to look for a head position that is neutral, in the sense of minimal muscle effort. This study shows that the use of a headrest may benefit the comfort experience of the passenger during flight. However, further research is necessary on the design of the headrest and the long-term effects of head support on comfort, discomfort, muscle activity and fatigue for watching IFE in a slouched posture.