Related Experiment Video
Updated: Jul 8, 2026
Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis
Published on: May 8, 2014
Paediatric Prosthetic Knee Design: The Technical Requirements of a Swing Phase Control Mechanism Are Correlated With
Insights
This study defines torque requirements for pediatric prosthetic knees, finding they correlate with child growth. This allows for affordable, adaptable prosthetic designs that accommodate growth.
Area of Science:
- Biomechanical Engineering
- Pediatric Orthopedics
- Rehabilitation Technology
Background:
- Lack of innovation in affordable pediatric prosthetic knees due to missing growth-considerate technical requirements.
- Childhood growth presents unique challenges for prosthetic device design and performance.
Purpose of the Study:
- To develop a modeling tool to define technical requirements for prosthetic knee swing phase control mechanisms (SPCM) throughout childhood growth.
- To establish design parameters for affordable pediatric prosthetic knees that accommodate growth.
Main Methods:
- Analysis of 3D gait data from 31 non-disabled children across various physical maturities.
- Creation of scaled musculoskeletal models for non-disabled and knee-disarticulation amputation models.
- Inverse dynamics analysis to determine SPCM torque requirements for a novel polycentric knee.
Main Results:
- Pediatric prosthetic knee SPCM torque requirements were significantly lower than non-disabled knees (17.9% extension, 66.3% flexion reduction).
- SPCM torque requirements strongly correlated with child body mass (extension) and height (flexion).
- Linear regression models accurately predicted torque requirements based on growth parameters.
Conclusions:
- Defined torque requirements for affordable pediatric prosthetic knee SPCM are linked to childhood growth parameters.
- Low-cost pediatric prosthetic SPCM designs can be tailored to accommodate growth.
- Developed musculoskeletal models enable future research in pediatric prosthetics.
Objective:
There is a lack of innovation in affordable prosthetic knee joints for children. One significant reason is the absence of technical requirements which consider the foundation of childhood: growth. This study aims to develop and use a modelling tool to determine the technical requirements throughout childhood growth for one prosthetic knee design feature, a swing phase control mechanism (SPCM).
Methods:
3D gait data of 31 non-disabled children across a range of physical maturities were analyzed. For each participant 2 models were created from a validated paediatric non-disabled musculoskeletal model. The model was first linearly scaled, then a corresponding unilateral right knee-disarticulation amputation model produced by removing segments below the knee and replacing with prosthetic componentry. Long established low-cost prosthetic componentry and a novel polycentric knee were implemented. For each participant, inverse dynamics were conducted and the SPCM torque requirements defined.
Results:
Prosthetic knee SPCM torque requirements were significantly less than the non-disabled knee to emulate non-disabled gait at free speed: 17.9% (± 10.2) and 66.3% (± 17.0) reduction in maximum extension and flexion torque, respectively. Maximum knee extension torque showed the strongest negative correlation with intact body mass (ρ = -0.6251) whereas flexion torque showed the strongest correlation with height (ρ = 0.6611). Corresponding linear regression fits produced RMSE of 1.91and 1.73 Nm, respectively. Results were also determined for slow and fast speeds.
Conclusion:
The torque requirements of an affordable paediatric prosthetic knee SPCM are defined and found to strongly correlate with parameters of childhood growth (body mass, height, and age).
Significance:
Current results recommend low-cost paediatric prosthetic SPCM designs can be tailored to accommodate growth. The creation of musculoskeletal models facilitate multiple future studies.
More Related Videos
Related Concept Videos
01:23Knee Joint
A total of seven ligaments support the knee joint. The patellar ligament, which is also attached to the quadriceps femoris group...
01:07Development of the Limb Synovial Joints
The mesenchymal stem cells differentiate into chondrocytes that form the hyaline cartilage, and later the cartilaginous model of the bone. This model further transforms into a bone. This process is known as endochondral ossification.
During development, the limbs...
01:26PD Controller: Design
Designing a continuous-data controller requires selecting and linking components like adders and integrators, which are fundamental in Proportional,...
01:07Time-Domain Interpretation of PD Control
Consider the example of control of motor torque. Initially, a positive...