Energy expenditure, and comfort in a modified wheelchair for people with hemiplegia: A controlled trial

Aim. The aim of this pilot study using non-disabled subjects was to measure energy expenditure, hand position and ride comfort, in a standard dual handrim Sunrise Breezy Wheelchair compared to one modified with a novel ergonomic self propelled steering (ESP) mechanism kit. The clinical reasoning underpinning the engineering design of the ESP kit was to develop a more ergonomically efficient mechanism for wheelchair steering and propulsion for individuals who had sustained cerebral vascular accidents. Methods. Ten non-disabled males participated in a repeated measures trial by driving two manual wheelchairs – a standard manual dual handrim wheelchair and one fitted with the steering conversion kit. Wheelchairs were randomly assigned, to participants who drove each wheelchair around a designated circuit. Oxygen consumption, carbon dioxide and heart rate were measured as indicators of ergonomic efficiency using a Cosmed analyser. Comfort for each wheelchair was measured using a validated questionnaire. Results. Heart rate (bpm), oxygen consumption (O2 ml/min) and exhaled carbon dioxide (CO2 ml/min) were significantly lower in the modified wheelchair (P < 0.001, P < 0.006 and P < 0.014, respectively). All comfort ratings were reported to be significantly greater in the ESP (P < 0.05). Conclusions. The ESP conversion kit transforms a standard Sunrise Breezy Wheelchair into one that is ergonomically more efficient and comfortable for non-disabled subjects.