Researchers conducted a study to determine the effectiveness and potential of powered knee and ankle prostheses, noting that the devices generate mechanical energy to replicate biological leg function but that direct comparisons with more commonly prescribed microprocessor-controlled knee prostheses are limited by methodological variability and small sample sizes.
Twelve adults with transfemoral or knee disarticulation limb loss or difference who regularly used microprocessor knees were enrolled in the crossover study. After device fitting and an average of ten training sessions with a powered knee and ankle prototype, the participants completed a comprehensive battery of biomechanical, physiological, and functional assessments. Tests were repeated using each participant’s prescribed prosthesis following a two-month washout period to reduce carryover effects. Paired statistical comparisons were used to evaluate differences across key outcome measures.
The researchers found that the participants walked slightly slower and exhibited marginally reduced swing time symmetry when using the powered prosthesis. However, there were no significant differences in metabolic energy cost between devices, despite the significant increase in weight of the powered prosthesis, the study found, which may suggest that the powered leg provided sufficient assistance to compensate for its added weight but did not yield improvements in walking speed, gait symmetry, or functional endurance.
The open-access study, “Beyond microprocessor knees: Exploring the potential of fully powered prosthetic legs,” was published in the journal Springer Nature.
