TY - JOUR
T1 - Mapping lines of non-extension in persons with lower limb amputation to aid comfort-driven prosthetic socket design
AU - Binedell, Trevor
AU - Gupta, Ujjaval
AU - Sithanathan, Bhuvaneswari
AU - Karupppasamy, Subburaj
AU - Blessing, Lucienne
PY - 2023/8
Y1 - 2023/8
N2 - Objective: This study aimed to develop a new technique to map the strain field for persons with lower-limb amputations to use for the design of comfortable prostheses. Methods: Using a DSLR camera with stenciled 2D markers, we demonstrated a technique to measure skin strain around the residual limb of persons with lower limb amputations. We used open-source software programs to reconstruct a series of cloud points derived from the pictures of the marked residual limb into 3D models, then calculated the minimum, maximum, and non-extension lines from directional strain fields. Results: A DSLR camera was successful in capturing 2D markers. The maximum mean principal strain was 68% ± 14%, observed around the patella. The minimum compressive mean principal strain of −31% ± 4% was observed posteriorly in the popliteal region of the knee. Although lines of non-extension (LoNE) appear separate in different participants, they are anatomically located in regions that could be generalized for the design of prostheses. Conclusions: Marker locations extracted from the video of different poses can be compared to calculate strains from which the position of LoNE can be generated. The use of LoNE could be valuable in reducing discomfort at the socket interface and informing future socket design.
AB - Objective: This study aimed to develop a new technique to map the strain field for persons with lower-limb amputations to use for the design of comfortable prostheses. Methods: Using a DSLR camera with stenciled 2D markers, we demonstrated a technique to measure skin strain around the residual limb of persons with lower limb amputations. We used open-source software programs to reconstruct a series of cloud points derived from the pictures of the marked residual limb into 3D models, then calculated the minimum, maximum, and non-extension lines from directional strain fields. Results: A DSLR camera was successful in capturing 2D markers. The maximum mean principal strain was 68% ± 14%, observed around the patella. The minimum compressive mean principal strain of −31% ± 4% was observed posteriorly in the popliteal region of the knee. Although lines of non-extension (LoNE) appear separate in different participants, they are anatomically located in regions that could be generalized for the design of prostheses. Conclusions: Marker locations extracted from the video of different poses can be compared to calculate strains from which the position of LoNE can be generated. The use of LoNE could be valuable in reducing discomfort at the socket interface and informing future socket design.
KW - Amputation
KW - Body surface
KW - Design
KW - Lines of non-extension
KW - Prostheses
UR - http://www.scopus.com/inward/record.url?scp=85164239671&partnerID=8YFLogxK
U2 - 10.1016/j.medengphy.2023.104018
DO - 10.1016/j.medengphy.2023.104018
M3 - Journal article
C2 - 37536839
SN - 1350-4533
VL - 118
JO - Medical Engineering & Physics
JF - Medical Engineering & Physics
M1 - 104018
ER -