A study explored effects of adding a toe joint to a passive prosthetic foot and found a decrease in push-off work when using the flexible toe joint prosthesis versus a locked toe joint prosthesis.
Researchers evaluated the kinematics, kinetics, rate of oxygen consumption, and user preference of nine healthy, active individuals with unilateral transtibial limb loss (K3/K4; age 41 ± 11 years). The participants walked on a passive prosthetic foot in two configurations: with a flexible, articulating toe joint and with a locked-out toe joint.
During level treadmill gait, the participants exhibited a 16 percent decrease in push-off work when using the flexible toe joint prosthesis versus the locked toe joint prosthesis and 10 percent less at the center of mass level.
However, the study’s authors noted that between configurations, participants exhibited little change in other gait kinematics or kinetics and no apparent or consistent difference in the rate of oxygen consumption, and that none of the traditional biomechanical or metabolic outcomes seemed to explain user preference.
The research team also observed that all participants who wore the prosthesis on their dominant limb preferred the flexible toe joint, and the other participants preferred the locked configuration, which they say may suggest a potential link between user preference and limb dominance, offering an interesting avenue for future research.
The open-access study, “Adding a toe joint to a prosthesis: walking biomechanics, energetics, and preference of individuals with unilateral below-knee limb loss,” was published in Nature.