Relationship Between The Quadriceps Muscle Stiffness And Patellar Alignment For Healthy People

Study Overview
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Brief Summary
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Patellofemoral pain is a common disease, and it often couples with patellar malalignment. Previously, imbalance of the different quadriceps muscle heads was believed to be a causative factor of patellar malignment. However, findings from electromyography studies on quadriceps activities and patellar alignment in the last two decades were inconsistent. In order to better understand the relationship between quadriceps muscle imbalance and patellar malalignment, shear wave elastography (SWE), which can measure the passive and active muscle stiffness, may shed some new lights to this area. This study aims to examine whether the quadriceps muscle stiffness can predict the patellar position. The healthy young adult will be recruited in this study. Active and passive quadriceps muscle stiffness will be measured with the SWE in different conditions and the result will be correlated with the patellar position measured with magnetic resonance imaging (MRI). Also, electromyography (EMG) activity will be measured during the active stiffness measurement so as to establish the level of agreement between the EMG and SWE data. Linear regression will be used to calculate the relationship between different factors. The total number of subjects needed will be 55 by setting an effect size of 0.15 with two predictors, 80% power, and α at 0.05 in the linear regression. This project will be conducted at PolyU campus and an MRI clinic in Hong Kong. Hopefully, it could be started in July 2021 and will last for 1 year.

Official Title
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Relationship Between The Quadriceps Muscle Stiffness And Patellar Alignment For Healthy People

Conditions
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Patellofemoral Maltracking

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy and in the range between 18 and 45 years. Exclusion Criteria: Knee pain in the last 3 months; Previous history of knee surgery; People with contraindications to having MRI scanning.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patellofemoral Joint Alignment measured by MRI scanning | Patellar displacement, patellar Alta/Baja and patellar tilt angle | Within 1 hour | 
| Muscle stiffness measured by ultragraph using shear wave elastography | Raw data of vastus lateralis, rectus femoris and vastus medialis obliquus shear modulus | Within 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle activity measured by electromyography | EMG data of vastus lateralis, rectus femoris and vastus medialis obliquus | Within 1 hour | 
| Muscle strength | Maximum isometric knee extensor muscle strength at specific joint angle (30 degrees and 60 degrees knee flexion) | Within 0.5 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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muscle stiffness, patellofemoral alignment