A Comparison Study Of The Off-Loading And Air Cushion For Wheelchair Curling Players With Spinal Cord Injury

Wanho Jang (Yonsei University)*; Jongbae Kim (Yonsei University College of Occupational therapy department); Wonseuk CHOI (Yonsei uni); Jeong-Hyun Kim (Yonsei University, Dept. of Occupational Therapy); Subin Hwang (Yosei University College of Occupational therapy department)


The purpose of this study is to compare the off-loading cushion and air cushion of the wheelchair curling players with spinal cord injury. The pressure and satisfaction of two cushions were measured by the pressure mapping system (x-sensor) and K-QUEST 2.0. As a result, the average pressure, ITs peak pressure, coccyx peak pressure and the contact area of the off-loading cushions were lower than air cushions. The satisfaction of the service of the off-loading cushion better than the air cushion. Both products of the satisfaction of product were not significantly different. Further study needs to increase the number of participants and investigate the effect on actual performance.


Wheelchairs curling is an adaptive version of curling, a popular sport in winter sports, for people with disabilities. Players are seated in wheelchairs and play the game used a delivery stick (Herzog, Swanenburg, Hupp, & Hager, 2018). To have a good performance, the stability of sitting position should be improved. Pressure must be evenly distributed to prevent skin damage (Brienza et al., 2010; Groah, Schladen, Pineda, & Hsieh, 2015). Therefore, a seating system is essential to improve performance and prevent injuries. The off-loading cushion reduces the pressure at ischial tuberosities and coccyx (Call, Hetzel, McLean, Burton, & Oberg, 2017; Crane, Wininger, & Call, 2016; Lim et al., 2007; Makhsous et al., 2009). We applied the off-loading cushions to wheelchair curling players and compared with the air cushions.



Participants were four Korean curling players. They were all national players with spinal cord injuries.


Figure 1: Molding and 3D Modeling
We made the off-loading cushions for four participants for a month. Participants sat in the vacuum bag for custom molding to match individual participants’ needs. We scanned the shape of the vacuum bag using a 3D scanner and modified the scanned data by 3D modeling software (Jang, Kim, & Kim, 2016). Notably, the areas contacted bone prominence were minimized.


Table 1: The pressure and contact area


Type of cushion



Average pressure



ITs peak pressure



Coccyx peak pressure



Contact area



We measured the pressure of sitting using x-sensor (Gunningberg, Sedin, Andersson, & Pingel, 2017). The pressure consists of the average, ITs peak (Ischial tuberosities) and coccyx peak pressure and the pressure. The satisfaction of the assistive technology service and the seating system evaluated by K-QUEST 2.0 (Korean-Quebec User Evaluation of Satisfaction with Assistive Technology, Version 2.0) (Jang, Choi, & Kim, 2018).


The Average pressure, IT peak pressure, coccyx peak pressure and the contact area of the off-loading cushions were lower than air cushions (Table 1). The service satisfaction of the off-loading cushion better than the air cushion. Both products of product satisfaction were not significantly different (Table 2).

Table 2: The satisfaction of service and product


Type of cushion



Satisfaction of service



Satisfaction of product




As a result of comparing the two products, the off-loading cushions were an advantage of pressure distribution. Satisfaction of service was also high for the off-loading seating system. However, there was no significant difference in the satisfaction of the product. It is difficult to generalize because there are few users. Further study is needed to see if the actual curling performance is improved.


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