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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: Knee osteoarthritis is one of the most common musculoskeletal problems that can affect activity daily living of patients. Many studies have indicated postural control deficits in these patients but the effect of dual tasking on postural control has not been examined yet. The aim of this study is to investigat the effect of cognitive task on postural control in the female patients with knee osteoarthritis.
Materials and Methods: Postural stability in knee OA patients and healthy subjects (20 subjects in each group ) in four positions was measured using the Force plate. Positions included double leg stance with closed or opened eyes with and without cognitive task. Area of COP and mean velocity (Vm) were measured for as static postural stability.
Results: Area under the curve increased in the double leg stance position in the patients significantly (P<0.05). While mean velocity decreased by performing a dual task (P<0.05). The response to dual-tasking was not significant between the 2 groups(P>0.05).
Conclusion: Postural control deficits and increased of center of pressure’s sway were identified in participants with Knee osteoarthritis. Also performance of a cognitive task resulted in decrease of postural sway, but the dual- tasking did not change the postural performance of knee OA patients compared to healthy subjects.

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  Background and Aim: Since many of people in their functional activities mostly place their knee joint in flexed position, the hamstring muscles tend to be shortened. On the other hand, shortness of these muscles affect the knee joint directly and the ankle and hip joints indirectly. It predisposes the individual to musculo-skeletal injuries. Thus, by early diagnosing and treatment of it, the tension may be decreased, the relaxation increased and the development of injuries can be prevented. In order to achieve this goal, various stretching techniques are used. The purpose of this study is to compare the effects of static and PNF stretching on shortness of hamstring muscles in 18-30 years young women.

  

  Materials and Methods: Thirty 18-30 years old nonathletic women without any history of pathology in hip, knee or back were selected. They were divided into three groups with 10 women in each group(static stretch, PNF stretch and control). The two stretch groups were received stretching program five days every week for three weeks, while the control group was not.

  Results: The range of knee extension of both groups of static and PNF stretching increased (p<0/05). However there was no significant difference between these two groups (p>0/05).

  

  Conclusion: Employing of both methods (static and PNF stretching) increase the hamstring muscles flexibility. However there was no significant difference between two groups in increasing rang of knee extension.

  

  Key words: Hamstring muscles, static stretching, PNF stretching

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Background and Aim: Patellofemoral pain syndrome (PFPS) is the most common overuse injury occurring at the knee. Reduction of proprioception, pain, changes in muscle activity patterns are seen in PFPS. Therefore these patients may demonstrate less balance. Thus the main objective of this study was to determine the postural control in patients with patellofemoral syndrome and compare it with healthy subjects.

Materials and Methods: Ten subjects (age 31.1 ± 5.31, weight 59.6 ± 8.95, height 1.62 ± 0.05) presenting with PFPS were compared with 10 matched control subjects (age 27.2 ± 1.81, weight 60.6 ± 2.36, height 1.67 ± 0.01).

Pain was measured with VAS scale and patella position was assessed using the method first described by McConnell. Force Plate was used to measures COP paths in sagittal and frontal plane with open and close eyes.

Results: The data showed that COP paths were different between PFPS and healthy subjects with open eyes in sagittal and frontal plane (P< 0.05). Means of COP paths increase in patients with PFPS. No differences were detected between PFPS and healthy subjects with closed eyes in sagittal and frontal plane.

Conclusion: Body sways increase in patients with PFPS with open eyes due to pain, lateral tracking patella and reduction of proprioception in knee.

Keyword:  Postural control, Patellofemoral syndrome, Open & close eye