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Purpose: Farmers with spinal cord injuries operate agricultural machinery and attempt to reduce their risk of pressure ulcers with aftermarket seat cushions. Research is limited in testing aftermarket cushions under dynamic conditions. The purpose of this study is to compare the seated pressure data of participants under five different types of seat cushions. We predict that seat cushions with greater immersion will result in lower maximum pressures resulting in a lower risk of developing a pressure ulcer. Methods: Using a quasi-experimental design, eight participants were recruited through an informal convenience sampling method. Participants met the inclusion criteria by having paralysis or a spinal cord injury that causes a significant impairment to their motor or sensory functions. An FSA pressure mapping system was used as the instrument to collect pressure data as participants completed five trials of sitting on a tractor seat while dynamically suspended on a platform constructed to replicate dynamic conditions. Testing trials were repeated on a tractor seat alone, with a foam cushion, with a low profile air bladder cushion, with a mid-profile air bladder cushion, and with a high profile air bladder cushion. The cushion conditions were randomized. Data was analyzed using SAS software. Results: Based on pressure mapping data collected, results indicate that all the aftermarket cushions provided a statistically significant lower dispersion index compared to the tractor seat alone. In comparison to each other, however, the dispersion indexes of the aftermarket cushions showed no statistically significant difference. Conclusion: Due to the limited number of participants in this study, statistical conclusions cannot be made at this time. The results of this study reveal the need for further research and field testing of seat cushions in an operating tractor. Future studies must also investigate how body mass index and body weight impact seat cushion performance.


Sponsored by the Southwest Center for Agricultural Health Education and Prevention