METABOLIC EVALUATION OF THE CRITERIA USED TO FIT ELBOW CRUTCHES BY MEASUREMENT OF OXYGEN-CONSUMPTION

Objective: To investigate if elbow crutches fitted using conventional guidelines are the most metabolically efficient, Design: Repeated meas ure connivance sample using crutch length as the independent variable. Setting: A university exercise physiology laboratory. Other Participa nt: Connivance sample of 10 students free from cardiovascular disease, with previous experience in crutch ambulation, and between the height s of 160 and 175cm. Four potential subjects refused to participate in the study. Interventions: Crutch length was adjusted using conventiona l guidelines, and to lengths 2.5cm above and below this setting. Oxyge n consumption was measured using indirect open-circuit spirometry duri ng the final 3 minutes of ambulation using self-selected walking speed s. Main Outcome Measure: Crutches adjusted to the convention setting a re not the most efficient in terms of metabolic energy expenditure. Re sults: A significant reduction in oxygen rate (p = .012), oxygen cost (p = .010), and respiratory exchange ratio (p = .009) were observed wh en comparing crutches adjusted to -2.5cm of the standard height with c onventional crutch height. Crutches adjusted 2.5cm above the standard height also required less energy, but these values failed to reach any statistical significance (p > .05). Conclusion: The importance of fit ting crutches to the correct length using conventional guidelines has not been substantiated in this study. Clinically, there should be a mo ve away from adherence to crutch-fitting criteria and more incorporati on of patient feedback to fit crutches to the optimal height. Future r esearch should evaluate the reliability of practical clinical measures such as heart rate and perceived exertion to fit crutches to the opti mal height. (C) 1996 by the American Congress of Rehabilitation Medici ne and the American Academy of Physical Medicine and Rehabilitation