Design and analysis of a new medial reciprocal linkage using a lower limb paralysis simulator

Ahmadi Bani, M; Arazpour, M; Farahmand, F; Sefati, S; Baniasad, M; Hutchins, SW; Vahab Kashani, R; Mousavi, ME

Abstract

STUDY DESIGN: A feasibility study on the effect of a new reciprocating orthosis on specific gait parameters for use by people with spinal cord injury.

OBJECTIVES: The aim of this study was to design and develop a new medial linkage orthosis (MLO) mechanism incorporating a reciprocating motion and to determine its efficacy in improving specific spatiotemporal, kinematic and kinetic parameters while ambulating when worn by healthy subjects. This was achieved via the use of a lower limb paralysis simulator (LLPS).

METHODS: A reciprocating joint with a remote center of motion was designed for use as an MLO. A prototype was fabricated and incorporated into an orthosis and equipped with a saddle to make the reciprocating motion possible. The efficacy of the orthosis was evaluated on four able-bodied healthy subjects who were trained to walk with the MLO attached to the LLPS.

RESULTS: Mean walking speed, stride length, stride time and cadence was 0.09±0.007 m s(-1), 0.42±0.01 m, 4.89±0.45 s and 29.54±4.32 steps min(-1), respectively, when healthy subjects walked with the new orthosis. The mean hip joint torque produced was 0.36±0.13 Nm.

CONCLUSION: In this study a new MLO was designed and fabricated that provided a reciprocating mechanism using a four-bar mechanism to set the virtual axis of the mechanism in a more proximal position than hinge-type joints. Further investigation is currently underway to assess its effect on gait parameters and energy expenditure in paraplegic patients.

Citation

Ahmadi Bani, M., Arazpour, M., Farahmand, F., Sefati, S., Baniasad, M., Hutchins, S., …Mousavi, M. (2015). Design and analysis of a new medial reciprocal linkage using a lower limb paralysis simulator. Spinal Cord, 53(5), 380-386. https://doi.org/10.1038/sc.2014.193

• Journal Article Type: Article
• Publication Date: Jan 1, 2015
• Deposit Date: Nov 4, 2016
• Journal: Spinal Cord
• Print ISSN: 1362-4393
• Publisher: Nature Publishing Group
• Volume: 53
• Issue: 5
• Pages: 380-386
• DOI: https://doi.org/10.1038/sc.2014.193
• Publisher URL: http://dx.doi.org/10.1038/sc.2014.193