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Background and aim: Knee osteoarthritis (OA) is one of the most common synovial joint diseases (i.e. weight bearing joints) of the human body. This problem probably is more common in Iranian society that is used to sit on the floor and carpet. Following knee OA, patients complain of pain, inflammation, decrease of range of motion and muscle weakness. Therefore, they can not independently do their activity of daily living (ADL). Consequently, the side effects of physical incapability may render to psychological problems and this in respect do affect on their quality of life.Various treatments such as pharmalogical, surgical and physiotherapy have been recommended at different stages of OA by specialist. In the present study, the effect of physical therapy agents (considering the point that physiotherapy has no or negligible side effects) have been studied on OA. 

Materials and methods: 40 patients participated in this study the patients were refereed by orthopedic surgeon to the physiotherapy clinic of the Faculty of Rehabilitation. University ethical committee approved the procedures. Patients were randomly divided in two groups and physiotherapy treatments were applied as following:

Group I.  Low Level Laser Therapy, heat, exercise.

Group II. Placebo (i.e. inactive Laser), heat, exercise.

Results: The result of current study shows that both methods of physical therapy were quiet efficient on 7 variables that measured in this study (p< 0.05).  However, the result of this study showed that in laser group, pain and speed of gait were more effectively influenced (p< 0.000 and p<0.048 respectively) in comparison with routine physiotherapy. Consequently, patients can fairly independently do their activity of daily living and this in respect may reduce the psychological side effects of illness. 

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Background and aim: Knee osteoarthritis is one of the most common musculoskeletal problems, can affect on patient's daily activity and produce dependency in their daily activity and functional disability The aim of present study is to compare static balance in patients with knee osteoarthritis and healthy subjects using force plate. 

Materials & Methods: Postural stability in knee OA patients and healthy subjects (each group 20 subjects) were measured by force plate. Two positions were selected double stance with closed or opened eyes. Range of fore/aft (Rfa) and Range of side ways (Rsw), were measured as static postural stability.

Results: Rsw increased significantly in the double stance position in patients group (P<0.05). Also in both groups, Rsw and Rfa in the double stance with closed eyes were more than of open eyes position (P<0.05).

Conclusion: Postural control deficits and increase of center of pressure's sway were identified in participants with knee osteoarthritis. Therefore, one of the most important goals of rehabilitation is to improve balance control in knee OA patients.

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Background and Aim: Given the biomechanical differences between over ground and treadmill walking, it is expected that the contraction of muscles should be also different, so exercise training in these scenarios may have various effects on trunk muscles. The aim of this study was to compare amplitude and duration of activation of trunk muscles during over ground and treadmill walking to prescribe a suitable exercise mode considering the special circumstances of each person.

Materials and Methods: Nineteen healthy 20-40 years old male with sedentary life style were selected via simple sampling. Surface electromyography of rectus abdominis, external oblique, longissimus and multifidus muscles were recorded.

 Results: In each gait cycle, there was not statistically significant differences on duration of trunk muscles activity between treadmill and over ground walking. The mean amplitude of these muscles was greater on treadmill in comparison with over ground and this difference was statistically significant for rectus abdominis (P=0.005), longissimus (P=0.018) and multifidus (P=0.044) muscles.

Conclusion: Stabilizing role of trunk muscles during walking causes them to be active throughout the entire gait cycle. The increased muscle amplitude on treadmill might show that more motor units may be recruited during the contraction, which is helpful in prescribing the appropriate type of exercise especially to patients who have trunk muscles weakness. 

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Background and Aim: Given the biomechanical differences between over ground and treadmill walking, it is expected that the contraction of muscles should be also different, so exercise training in these scenarios may have various effects on trunk muscles. The aim of this study was to compare amplitude and duration of activation of trunk muscles during over ground and treadmill walking to prescribe a suitable exercise mode considering the special circumstances of each person. 

Materials and Methods: Nineteen healthy 20-40 years old male with sedentary life style were selected via simple sampling. Surface electromyography of rectus abdominis, external oblique, longissimus and multifidus muscles were recorded.

Results: In each gait cycle, there was not statistically significant differences on duration of trunk muscles activity between treadmill and over ground walking. The mean amplitude of these muscles was greater on treadmill in comparison with over ground and this difference was statistically significant for rectus abdominis (P=0.005), longissimus (P=0.018) and multifidus (P=0.044) muscles.

Conclusion: Stabilizing role of trunk muscles during walking causes them to be active throughout the entire gait cycle. The increased muscle amplitude on treadmill might show that more motor units may be recruited during the contraction, which is helpful in prescribing the appropriate type of exercise especially to patients who have trunk muscles weakness.