@2024 Afarand., IRAN

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ISSN: 2008-2630    Iranian Journal of War & Public Health 2016;8(2):75-82

Background
Using prosthetic makes changes for amputated people in walking [1, 2].
Previous Studies
… [3-19]. Some studies have shown that time to reach peak of reaction force of the earth on the healthy leg is less than the prosthetic leg [20], and peak of braking force and the propulsion impulse in prosthetic legs are more than healthy legs [21,24,25]...[22,23,26].
Aim(s)
The aim of this study was to analyze the components of earth’s reaction forces in healthy leg and prosthetic leg in the patients with unilateral below the knee amputation while walking.
Research type
This study is observatory _ cross-sectional.
Research society, place and time
The study was done over 10 patients with unilateral below the knee amputation, based on non-probability purposive sampling method from rehabilitation clinics of Isfahan in 2013.
Sampling method and number
The sample size was considered 15 persons in a group using 1.70 for standard deviation in Lehrer formula [27] , using power 90%, and considering 35% risk of fall that 5 persons of case studies couldn’t complete the tests and failed. Entry requirement for the study involved: being male, amputation below the knee, no history of important surgery or any illness affecting walking skills in the past 6 months, absence of cardiovascular disease, independent walking ability, the use of prosthesis below the knee and the lack of other aids except prosthetic .Exclusion criteria were the Inability to follow the orders and failure to complete the test.
Used devices&materials
Qualisys motion analysis system (Qalisis Company; Switzerland) consisting seven cameras was used to record different gait phases. Reliability and validity of the Qualisys Motion Analysis System has been studied. Motion Analysis System is a precise system for measuring distance and its error measurement is 0.6 mm at a distance of 3 meters [28] .In case of measuring earth ‘s reaction forces , Kistler force plate by dimensions of 500*600 mm (model AA 9260; Kistler company, Switzerland) was used. This force plate was in the middle of the footstep. Cameras and force plate were (working) at the same time .the company has reported dynamometer‘s precision very high and the errors in the system has been reported less than 1% [29]. A 10-meter-long hiking path along the laboratory was considered that the starting point for walking for case studies was 5 Km distances from the center of force plate. Markers placement protocol on the body was based on the protocol approved by the University of Strathclyde (figure 1) [30]. Data collection frequency for both systems of Qualisys motion analysis and force plate was 120 Hz. The data was filtered with a low pass filter with a frequency of 10 Hz [31]. Kinematic data was recorded using Qualisys software (version 7.2; Qualisys Company, Switzerland). After calibrating the camera and force plate, at first, case studies anthropometric data including weight, height and length of the right and left foot were recorded. One test was taken on case study, in standing position and then the subject was walking in the regular speed through determinate path and without shoes and the markers image while walking were recorded along with force plate data. Each sample was repeating three trial walking and the average of the three trials walk was used for final analysis. Qualisys software was used in case of recording standing and swing phases of the data and extracting of the earth‘s reaction forces during gait cycle. Variables of the study included: The first and second peaks and force earth ‘s reaction vertical valleys, The first and second anterior posterior earth ‘s reaction force peak , internal external earth ‘s reaction force peak, the total hit ,the brakes hit ,the pushing hit , vertical, external and internal hit , load speed and unload speed {figure 2). Data collection frequency for both systems of Qualisys motion analysis and force plate was 120 Hz. The data was filtered with a low pass filter with a frequency of 10 Hz [31]. Kinematic data was recorded using Qualisys software (version 7.2; Qualisys Company, Switzerland). After calibrating the camera and force plate, at first, case studies anthropometric data including weight, height and length of the right and left foot were recorded. One test was taken on case study, in standing position and then the subject was walking in the regular speed through determinate path and without shoes and the markers image while walking were recorded along with force plate data. Each sample was repeating three trial walking and the average of the three trials walk was used for final analysis. Qualisys software was used in case of recording standing and swing phases of the data and extracting of the earth‘s reaction forces during gait cycle. Variables of the study included: The first and second peaks and force earth ‘s reaction vertical valleys, The first and second anterior posterior earth ‘s reaction force peak , internal external earth ‘s reaction force peak, the total hit ,the brakes hit ,the pushing hit , vertical, external and internal hit , load speed and unload speed (figure 2). Shapiro-Wilk normality test was used for normality of data distribution. After ensuring the normal distribution of data, it was analyzed by SPSS 22 software using independent T test.
Findings by Text
10 unilateral amputated below the knee persons were participated in the study. The participants mean age in the study was 49.30 ± 3.80 years, their mean weight was 77.50 ±9.90 Kg and their imean height was 173.20 ± 3.40 cm. The causes of injury were Trauma for 9 persons and burning for one person that for 6 persons it was related to the left leg and for 4 cases it was related to the right leg. Modular system with Ottobock single-axis claw was the prostheses that had been used in 5 cases and in each of the other 5 people involved : Pedilini System with Ottobock sachs claw and soft foam socket , modular system with single-axis claw and liner soft socket , modular system with Ottobock sachs claw and Cuff strap , modular system of chinese sachs claw and modular system with sachs claw and cuff strap. The propulsion impulse and vertical impulse showed significant difference between healthy leg and prosthetic leg in the patients with unilateral below the knee amputation. There was no significant difference among other variables including braking impulse, internal-external impulse, and general impulse, between healthy side and prosthetic side. In the prosthetic leg, the propulsion impulse and vertical impulse of the reaction force of the earth were lower than the healthy leg by 5.82N/S,63.25N/S, respectively. There was a significant difference in peak of internal-external force between healthy and prosthetic leg of the patients with unilateral below the knee amputation and in prosthetic side, it was less than healthy leg by 9.46N/s. There was no significant difference between healthy and prosthetic leg in terms of the peaks of braking forces, propulsion forces, and first and second peak and earth valley reaction forces. Although there was no significant differences between the first peak anterior posterior force on healthy side and prosthetic side, the first peak in the anterior posterior force in prosthetic leg was less than healthy leg by 27.05N/S. Time to reach the peak reaction force of the earth and loading speed on both of the healthy and prosthetic sides was significantly different. Speed to peak reaction force of the earth on prosthetic side was more than healthy side by 4.9 N/S. In addition, loading speed on prosthetic leg was less than healthy side by 12.8N/S. There was no significant difference between healthy and prosthetic leg in case of uploading speeds (table 1).
Main comparison to the similar studies
There is a similarity between the results of this study with the results of other studies , which have shown that there is no significant difference between prosthetic leg and healthy leg in case of first and second peak of vertical impulse, and it appears to contradict other studies that has shown there is a significant difference in braking and propulsion impulse earth’s reaction force between healthy leg and prosthetic leg [21,24,25]. Castro et al showed that braking impulse force and posterior force in healthy leg of the patients with unilateral below the knee amputation was significantly more than prosthetic leg that is matching with the present study result… [32]
Suggestions
It is suggested that in future studies more case studies and different walking speed be done.
Limitations
Of the limitations of this study were the use of only one force plate inside the laboratory, the low number of subjects, the absence of an electromyography to measure the muscle activity of subjects.
Conclusions
Greater propulsive impulse, vertical impulse, and loading force on the healthy leg than the prosthetic leg in the patients with unilateral below the knee amputation shows that there is a greater loading time interval on the healthy leg.
Acknowledgments
All case studies are appreciated by the authors of the study.
Conflict of interest
There is no conflict of interest.
Ethical Permissions
Written contest was acquired by case studies of the study.
Funding Sources
Deputy of research and technology, Isfahan University of Medical Sciences funded this study.

TABLES and CHARTS

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