Design and analysis of a new medial reciprocal linkage using a lower limb paralysis simulator.
METHODS
A feasibility study on the effect of a new reciprocating orthosis on specific gait parameters for use by people with spinal cord injury.


OBJECTIVE
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.


CONCLUSIONS
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.
Department of Orthotics and Prosthetics, University of Social Welfare and Rehabilitation Science, Tehran, Iran.
M
M
Ahmadi Bani
Department of Orthotics and Prosthetics, University of Social Welfare and Rehabilitation Science, Tehran, Iran.
M
M
Arazpour
1] Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran [2] Research Center of Biomedical Technology and Robotics, Tehran University of Medical Sciences, Tehran, Iran.
F
F
Farahmand
Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran.
S
S
Sefati
1] Mechanical Engineering Department, Sharif University of Technology, Tehran, Iran [2] Research Center of Biomedical Technology and Robotics, Tehran University of Medical Sciences, Tehran, Iran.
M
M
Baniasad
University of Salford, IHSCR, Faculty of Health and Social Care, University of Salford, Salford, UK.
S W
SW
Hutchins
Department of Orthotics and Prosthetics, University of Social Welfare and Rehabilitation Science, Tehran, Iran.
R
R
Vahab Kashani
Department of Orthotics and Prosthetics, University of Social Welfare and Rehabilitation Science, Tehran, Iran.
M E
ME
Mousavi
D000293:Adolescent; D000328:Adult; D001696:Biomechanical Phenomena; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006621:Hip Joint / Q000503:physiopathology; D006801:Humans; D008124:Locomotion / Q000502:physiology*; D035002:Lower Extremity / Q000503:physiopathology*; D008297:Male; D009989:Orthotic Devices; D010243:Paralysis / Q000209:etiology / Q000473:pathology*; D016059:Range of Motion, Articular; D013119:Spinal Cord Injuries / Q000534:rehabilitation*; D018709:Statistics, Nonparametric; D055815:Young Adult