LAUSR

OBJECTIVE To compare the metabolic demands of walking in individuals with lower limb injury with and without ankle-foot orthosis (AFO) use. A secondary aim was to compare these results to individuals to those from individuals with unilateral transtibial amputation and able-bodied controls. DESIGN Cross Sectional Study. SETTING Two clinical research centers PARTICIPANTS: Thirteen individuals with lower limb injury who used a passive-dynamic AFO underwent metabolic analysis at three standardized speeds with and without their AFO. Results were compared to individuals with unilateral transtibial amputation (TTA) who used a passive prosthetic foot and able-bodied controls with no musculoskeletal, neurological, or cardiovascular deficits. MAIN OUTCOME MEASURES Oxygen consumption, heart rate, and rating of perceived exertion. RESULTS The use of the passive-dynamic AFO did not significantly change energetic demand (oxygen consumption, heart rate, perceived exertion) in participants with a LL injury. Heart rate (p<0.037) was significantly greater than able-bodied controls but perceived exertion was significantly lower (p≤0.031). There were no significant differences between participants with a LL injury (with or without the AFO) and individuals with TTA. CONCLUSION Many individuals with LL injuries may expect to use passive-dynamic AFOs at little-to-no metabolic consequence. The stabilizing and assistive benefits of the AFO likely balance with its well-known range of motion limitations and power reductions. Passive-dynamic AFO use can sometimes be an alternative for individuals considering TTA. These results support that AFO users may be able to achieve similar energetic demands as those with amputation.