Individuals using traditional axillary crutches to ambulate expend approximately twice as much energy as individuals who perform able-bodied gait. A relatively novel spring-loaded crutch now being marketed may reduce metabolic energy expenditure during crutch ambulation. This idea, however, had not yet been tested.
To determine whether the novel spring-loaded crutch reduces oxygen consumption during crutch ambulation, relative to traditional-crutch ambulation. A secondary purpose was to evaluate the design for subject-perceived comfort and ease of use.
10 able-bodied men and 10 able-bodied women.
The independent variable was crutch design. Each subject ambulated using 3 different crutch designs (traditional, spring-loaded, and modified spring-loaded), in a randomized order.
Main Outcome Measures:
The primary dependent variable was oxygen consumption. Secondary dependent variables were subject-perceived comfort and ease of use, as rated by the subjects using a 100-mm visual analog scale. Dependent variables were compared among the 3 crutch designs using a 1-way repeated-measures ANOVA (α = .05).
Oxygen consumption during spring-loaded-crutch ambulation (17.88 ± 2.13 mL · kg−1 · min−1) was 6.2% greater (P = .015; effect size [ES] = .50) than during traditional axillary-crutch ambulation (16.84 ± 2.08 mL · kg−1 · min−1). There was no statistically significant difference (P = .068; ES = −.45) for oxygen consumption between spring-loaded-crutch ambulation and ambulation using the modified crutch (17.03 ± 1.61 mL · kg−1 · min−1). Subjects perceived the spring-loaded crutch to be more comfortable (P < .001; ES = .56) than the traditional crutch. There was no difference (P = .159; ES = −.09) between the spring-loaded and traditional crutches for subject-perceived ease of use.
Compared with traditional axillary crutches, the novel spring-loaded crutch may be more comfortable but does not appear to benefit subjects via reduced metabolic energy expenditure.
The authors are with the Dept of Exercise Sciences, Brigham Young University, Provo, UT.