Transfemoral amputee trip recovery strategies
To aid trip recovery the ability of the support leg is more crucial than that of the tripped leg. In transfemoral amputees this means that tripping with the sound leg can be more disastrous and prosthetics with real-time recovery strategies programming could be developed to overcome this.
Tripping and falling is a hazard for amputees, with some studies suggesting they are just as vulnerable as balance impaired individuals. Half of transfemoral amputee falls result in injury, and can impede daily life. For an able bodied person three elements are critical to fall recovery:
- Reaction time
- Speed of movement on the tripped side
The researched looked at the kinematic response of the transfemoral amputee in tripping and compared against common strategies for fall recovery;
- Elevation (Foot lifted and placed further forward)
- Delayed-lowering strategy (Foot lifted and placed further back or same spot)
- Lowering strategy (Foot not lifted but placed further back or same spot)
- Incomplete arrest (Foot not lifted but placed further forward)
Trip strategies were identified based on trajectory of foot on the tripped side and identified that alternative stepping pattern was disrupted and two additional strategies commonly adopted;
- Hopping strategy: Both feet are brought forward during flight phase, trying to jump over the perceived obstacle.
- Skipping strategy: Extra step taken with tripped foot coming down quickly before supporting foot moves.
The common strategies were most commonly adopted, however the prevalence of the novel strategies were most notable when the tripping occurred to the sound limb and the prosthetic was asked to recover.
Video: an experimental set-up to investigate tripping
Which trip recovery strategie do you most commonly adopt?
> From: Shirota et al., J Neuroeng Rehabil 12 (2015) (Epub ahead of print). All rights reserved to BioMed Central. Click here for the Pubmed summary.