Analysis of hand pressure in different crutch lengths and upper-limb movements during crutched walking

Hand pressure in crutch is important as it is directly related to the comfort of the patients using crutches. However, little research has been done on dynamical hand pressure during crutched walking. This study investigated hand pressures and joint movements in the upper limb with the different crutch lengths during crutched walking. Twelve healthy male adults participated in the study, and performed crutch-supported walking at bi-crutch and single-foot way. A specific mat of pressure sensors was designed to measure the hand pressure of the palm and fingers and a motion capture system used to capture the movements at the shoulder and elbow. It was found that when walking speeds were between 0.5 and 1.0 m/s, maximum pressure and force were approximately 120 kPa and 100 N respectively in the hand the ranges of motion were from 28 to 60 deg at the shoulder and from 15 to 30 deg at the elbow. The results showed that the pressure-time integral and force-time integral in the hand are higher when using a traditional standard crutch length than using longer or shorter lengths. The visual analogue scores of conformable degree showed that the participants are favourite for a traditional standard crutch length. The pressure and kinematic data collected provide a set of database available for crutch manufacturer, glove designer and clinicians as reference when they need. Relevance to industry: Crutched walking usually causes hand uncomfortable or injury. Our study provides the first experimental data of hand pressures and the joint movements in the upper limbs at different crutch lengths. These results are valuable for devising gloves for patients, thus improving the life quality of the patients using crutch.