Muscle Activation in Knee Osteoarthritis

Study Overview
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Brief Summary
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Muscle activity, as a possible fundamental cause of functional limitation, has been extensively investigated in knee osteoarthritis (KOA). Many trials investigated muscle activity during dynamic movements and functional tasks in KOA. In addition, gender-related differences has been also investigated during functional movements in KOA. However, no trial investigated gender-related differences in muscle activation during static movement in KOA.

Detailed Description
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Muscle activity, as a possible fundamental cause of functional limitation, has been extensively investigated in knee osteoarthritis (KOA). Interestingly, studies concentrated mainly on investigation of muscle activity during dynamic movements and different functional tests. Moznuzzaman et al displayed greater muscle activation during sitting to standing test (STS) and standing to sitting test in KOA patients compared to healthy participants. Interestingly, some studies investigated muscle activation standing up from a knee-height seat during STS and illustrated a greater muscle activation amongst KOA patients compared to healthy controls. Moreover, Amer et al found greater muscle activation while performing STS from a lower height seat compared to a knee-height seat amongst women and men patients with uni/bilateral KOA. These findings might be of interest due to compensatory mechanisms observed by female patients during STS transition increases loading on the joint surfaces and consequently leading to progression of KOA. Furthermore, different studies also presented gender-differences of muscle activation during different weight-bearing tasks (gait, STS, stair ascend/descend, and squat) amongst patients with KOA and healthy control. Interestingly, both studies showed women with KOA representing higher muscle activation compared to men. Therefore, an analytical comparative study might be useful for identification of gender-differences in muscle activation amongst patients with KOA. Investigation of static muscle activity during functional movements is very rare in KOA. Zhang et al investigated muscle activation after single whole body vibration trial in standing position at 0°, 30° and 60° static knee flexion angles amongst women with KOA. Authors found that muscle activation in 60° was greater compared to 30°, and it was also greater in 30° compared to 0°. Based on our literature search, no further study examined muscle activity in static knee flexion in KOA. However, investigating static knee flexion might be useful as it could be related to different knee moments in KOA.

Official Title
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Gender Difference of Muscle Activation Amongst Patients With Knee Osteoarthritis

Conditions
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Knee Osteoarthritis

Intervention / Treatment
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* Device: Electromyography (EMG) measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: radiologically diagnosed KOA based on the Kellgren-Lawrence grading system 1-3, age above 60 years at least 60° active knee flexion sufficient mental status Exclusion Criteria: acute inflammation of the knee intraarticular injections within the last 3 months total knee replacement in the opposite side class II obesity (body mass index, BMI>35kg/m2) severe degenerative lumbar spine disease (e.g., spondylolisthesis) systemic inflammatory arthritic or neurological condition conservative intervention attendance within 6 months contraindication to conservative therapy and manual therapy unstable heart condition complex regional pain syndrome

Ages Eligible for Study
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Minimum Age: 60 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Men group<br>Muscle activity amongst men with KOA | Device: Electromyography (EMG) measurement<br>* Electromyography (EMG) measurement of m. quadriceps femoris and semitendinosus muscle during static functional tasks<br>|
| Women group<br>Muscle activity amongst women with KOA | Device: Electromyography (EMG) measurement<br>* Electromyography (EMG) measurement of m. quadriceps femoris and semitendinosus muscle during static functional tasks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patients' baseline state | Measurement of patients' pain, stiffness and functional state based on WOMAC | within 1 day | 
| Patients' baseline pain | Measurement of patients' pain based on Numeric Pain Rating Scale | within 1 day | 
| Patients' baseline knee flexion | Measurement of patients' active knee flexion in supine | within 1 day | 
| Patients' baseline knee flexion in standing position | Measurement of patients' active knee flexion during weight-bearing | within 1 day | 
| Muscle strength of m. quadriceps femoris | Measurement of muscle strength of m. quadriceps femoris in 0, 35 and 60 degree | within 1 day | 
| Muscle strength of hamstring muscles | Measurement of muscle strength of m. semitendinosus, semimembranosus and biceps femoris in 0, 35 and 60 degree | within 1 day | 
| Muscle activation in 30 degree static knee flexion | EMG measurement of muscle activation during 2-leg 30 degree static knee flexion | within 1 day | 
| Muscle activation in 60 degree static knee flexion | EMG measurement of muscle activation during 2-leg 60 degree static knee flexion | within 1 day | 
| Muscle activation during stepping up a stair | EMG measurement of muscle activation during stepping up on a stair | within 1 day | 
| Muscle activation during stepping down a stair | EMG measurement of muscle activation during stepping down from a stair | within 1 day | 
| Muscle activation during stepping down side-ways a stair with affected leg | EMG measurement of muscle activation during stepping down side-ways a stair with affected leg | within 1 day | 
| Muscle activation during stepping down side-ways a stair with opposite leg | EMG measurement of muscle activation during stepping down side-ways a stair with opposite leg | within 1 day | 
| Muscle activation in one-leg standing position | EMG measurement of muscle activation in one-leg standing position | within 1 day |