Below-knee amputee gait with dynamic elastic response prosthetic feet: a pilot study

Area of Science:

• Biomechanics
• Prosthetics and Orthotics
• Rehabilitation Engineering

Background:

• The development of advanced prosthetic feet aims to improve gait and reduce energy expenditure for amputees.
• Dynamic Elastic Response (DER) prosthetic feet represent a newer technology compared to traditional Solid Ankle Cushion Heel (SACH) feet.

Purpose of the Study:

• To compare the gait kinematics and energy expenditure of below-knee amputees using four different DER prosthetic feet against a standard SACH foot.
• To identify if any DER prosthetic feet demonstrate trends towards producing more optimal gait patterns.

Main Methods:

• A pilot study involving five below-knee amputees was conducted.
• Each participant walked with four distinct DER prosthetic feet (Flex-Foot, Carbon Copy II, SEATTLE, STEN) and one SACH foot for one month each.
• Gait analysis and energy expenditure testing were performed at the Pathokinesiology Laboratory.

Main Results:

• Minimal differences in gait parameters were observed between the five prosthetic feet during both free and fast walking paces.
• The Flex-Foot showed significantly different ankle kinematics but did not improve walking velocity or energy cost compared to others.
• No clinically significant advantages were found for any tested prosthetic foot during level ground walking.

Conclusions:

• This pilot study suggests that for level ground walking at free or fast paces, current DER prosthetic feet do not offer clinically significant advantages over the SACH foot.
• Further research with larger sample sizes is recommended to explore potential subtle differences and long-term benefits.
• Future studies should focus on specific patient populations and varied walking conditions to better evaluate prosthetic foot performance.