The influence of a user-adaptive prosthetic knee on planned gait termination.

The added value of user-adaptive prosthetic knees has been predominantly evaluated in level walking or ramp/stair negotiation. Previous studies indicate that the activity pattern of individuals with an amputation mainly consists of short periods of continuous walking, indicating that a high percentage of ambulatory activity involves gait termination. The potential added value of user-adaptive prosthetic knees in gait termination has not been studied yet. Ten individuals with an amputation were measured with their own non-microprocessor controlled prosthetic knee and with the Rheo Knee II (a user-adaptive prosthetic knee). Spatiotemporal, kinematic and kinetic variables were measured. We found that the Rheo Knee II had no effect on the studied outcome parameters when compared to the non-microprocessor controlled prosthetic knee. We also found that the intact leg was responsible for producing the deceleration forces irrespective whether the last step was made by the intact or prosthetic leg. In conclusion we found that the prosthetic leg is limited in producing deceleration forces. Although user-adaptive prosthetic knees claim to increase stance stability, the added value of the Rheo Knee II on the studied outcome parameters is limited.