Analysis of hand pressures related to wheelchair rim sizes and upper-limb movement

Hand pressure is important in wheelchair design as it is directly related to the comfort or injury of the patients/sportsmen using the wheelchair. However, little research has been done on hand pressure during wheelchair propelling. This study aimed to measure hand pressures and joint movements in the upper limb with the different size of wheelchair rims during manual propulsion. Nine healthy adult subjects participated in the study, and they were required to perform wheelchair propelling at their self-comfortable way. A specific mat of pressure sensors was used to measure the hand pressure of the palm and a motion capture system to capture the movements at the shoulder and elbow. The results showed that under the condition of the speeds between 0.7-1.7m/s, the mean hand pressures were ranged between 180 and 200kPa on the palm; the ranges of motion were from 30° to 70° at the shoulder and from 15° to 50° at the elbow. The pressure and kinematic data collected provide a set of database available for wheelchair manufacturer, glove designer, clinicians and sports exerciser as reference when they need. Relevance to industry: Pushing wheelchair usually causes hand uncomfortable or injury. Our study provides the first experimental data of hand pressures associated the joint movements in the upper limbs at different sizes of push-rims. These results are valuable for devising gloves for patients, thus improving the life quality of the patients using wheelchair.