Introduction
The alignment of a prosthesis is clinically determined based on observations
by clinicians and the subjective perception of amputees during gait.
However, this process has been reported to be unreliable. Socket reaction
moment has been reported to be significantly impacted by alignment changes,
but the impact of these alignment changes on other gait parameters is
unclear. The aim of this study was to investigate the effects of coronal
alignment changes of a transtibial prosthesis on socket reaction moment,
spatiotemporal parameters, and perceptions of alignment during gait in
amputees.
Methods
Nine individuals with transtibial amputation participated in this study.
Socket reaction moment and spatiotemporal parameters (step time, step
length, step width, single limb support time, cadence, and gait speed) were
measured under nine coronal alignment conditions (angulation: ±3°, ±6°,
translation: ±5 mm, ±10 mm, and baseline) using a three-dimensional motion
capture system (Vicon) and an embedded load-cell system (Europa™). In
addition, subjective perceptions of alignment were examined.
Results
Coronal alignment changes of the transtibial prostheses demonstrated
significant changes in socket reaction moment; however, no significant
changes were found with spatiotemporal parameters or the amputee’s
perception.
Conclusion
Measurement of socket reaction moment, along with the embedded load-cell
system, may be a better metric for tuning the coronal alignment of
transtibial prostheses compared to spatiotemporal parameters and amputee’s
perceptions.