Projects

Why Does Quadriceps Weakness Persist after Total Knee Replacement?

An Exploration of Neurophysiological Mechanisms

Total knee replacement is a commonly performed surgery for treating end-staged knee osteoarthritis. Although most people recover well after surgery, weakness of the quadriceps muscles (the front thigh muscles) persists long after the surgery (at least for 12 months), despite intensive physiotherapy and exercise. Quadriceps muscle weakness is known to be associated with more severe pain and greatly affect daily activities.

This study aims to investigate the mechanisms underlying weakness of the quadriceps muscles in people with knee osteoarthritis and total knee replacement. We hope to better understand the relationship between the changes of the brain and a loss of quadriceps muscle strength after total knee replacement.

The study might be a good fit for you if you:

• Scheduled to undergo a total knee replacement;
• The surgery is scheduled within the next 4 weeks;
  • Do not have a previous knee joint replacement in the same knee;
  • Do not have high tibial osteotomy;
  • Do not have neurological disorders, epilepsy, psychiatric conditions, other chronic pain conditions;
  • Do not have metal implants in the skull;
  • Do not have a loss of sensation in the limbs.

If you decide to take part you would:

• Be contacted by the researcher to determine your eligibility for the study
• Be scheduled for testing if you are eligible and willing to take part in the study
• Sign the Consent Form when you attend the first testing session
• Attend 3 testing sessions (approximately 2 hours per session): 1) before total knee replacement, 2) 3 months and 3) 6 months after total knee replacement. The testing will include several non-invasive measures of brain representations of the quadriceps muscles, central pain mechanisms, and motor function and questionnaires.

Will I be paid to take part in the research study?

You will be reimbursed ($50.00 per session) for travel and parking expenses associated with the research study visits.

If you would like more information or are interested in being part of the study, please contact:

Name: Dr Wei-Ju Chang

Email: w.chang@neura.edu.au

Phone: 02 9399 1260

This research is being funded by the Physiotherapy Research Foundation.

ReNeuWell^® is your home for neuroscience-based information and personalised positive psychology activities to guide you towards greater resilience and mental wellbeing.

What is ReNeuWell®?

How does it work?

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What is the time commitment?

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What does the app cost?

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Funding and partners

Further questions

High blood pressure is related to the development of cerebral small vessel disease, retinal microvascular abnormalities, eye diseases (e.g. cataract and glaucoma), reduced visual acuity, and dementia. Cerebral small vessel disease, retinal microvascular abnormalities, eye diseases and vision are also related to the risk of dementia. Moreover, socioeconomic inequalities are related to blood pressure and dementia and may consequently shape the associations between blood pressure and risk of cerebral small vessel disease, retinal microvascular abnormalities, eye diseases and dementia. 

To date, there is no study investigating the indirect effects of cerebral small vessel disease, retinal microvascular abnormalities, eye diseases and vision impairment on dementia or cognitive decline and no study evaluating the influence of different socioeconomic indicators on these associations.  

Frailty is a term that is often used in clinical or research settings to describe someone who has less ability to recover from disease or illness, someone who has less reserve and is more vulnerable. 

Frailty can occur at any age but it gets more common as we get older. Being frail also makes us more likely to need additional care such as care at home or hospital care. But the good news is that frailty can be modified, it can be stabilised or even reversed.  

Our team has several projects that are investigating frailty, from understanding the best ways to measure and approach frailty in community settings to testing ways that we might be able to reduce it. Our current projects are shown below:  

The INTERgenerAtional Clinical Trial In at risk Older adults and preschool childreN (INTERACTION) (ACTRN12622000368730).  

In the INTERACTION trial led by Associate Professor Ruth Peters, we are collecting data to help us understand whether an intergenerational program (that is bringing older adults and pre-schoolers together to complete purposeful structured activities) helps to reduce frailty in the older adults. We are also measuring what happens to the children as we think it will help them with things like school readiness.  

Associated people: Ruth Peters, Ebony Lewis, Mae Lim, Christine Zammit, Nicole Ee, Gail Kenning.  

Understanding frailty in Indigenous populations  

In this study led by Ebony Lewis, we are mapping the rates of frailty in Indigenous adults, looking at what proportion of people have frailty, what proportion are developing frailty over time and what that means for future engagement and care.  

Project 1 – Views that older First Nations people hold about frailty  

To understand the views that older Aboriginal and Torres Strait Islander people in Sydney hold about frailty and any needs and suggestions around frailty and ageing to support health and wellbeing as people age 

Project 2 – Incidence and prevalence of frailty in First Nations Peoples in New South Wales  

To describe the frailty profile of older Aboriginal and Torres Strait people using data from a population-based cohort in NSW 

Associated people: Ebony Lewis, Dr Kylie Radford, Dr Nicole Mealing, A/Prof Ruth Peters.  

Frailty and high blood pressure 

 In this study led by Associate Professor Ruth Peters, we are looking at whether frailty mediates the impact of blood pressure-lowering medication. This is important since both high blood pressure and frailty become more common as we get older.  

In the last 30 years we have learned an enormous amount about the risk factors for dementia and cognitive decline and whether they have their biggest impact in mid and/or late life. Now we are starting to extend our understanding to earlier adult life and even childhood. To do this we are synthesizing the academic evidence using systematic review and meta-analysis techniques to deliver an overview of the current evidence at younger ages. We have recently published an article bringing together the available data on the impact of high blood pressure in childhood and early adulthood on cognitive function and are now looking at other modifiable risk factors that might be present in earlier life. This is important because the more we can understand about when and how the risk factors for poorer cognitive function have their impact, the better we can target our risk reduction strategies.  

Osteoarthritis affects more than 20% of Australians aged over 60. The knee joint is commonly affected, causing persistent pain and difficulty in daily activities. Although exercise is the cornerstone of conservative treatment for knee osteoarthritis and recommended in all international guidelines, its effects are, at best, moderate.

BOOST is a ‘proof of concept’ study to explore the use of a novel intervention combining non-invasive brain stimulation and exercise therapy in people with knee osteoarthritis. This intervention applies repetitive transcranial magnetic stimulation, a safe and painless non-invasive brain stimulation, targeting specifically the brain region involved in pain processing and motor function to enhance the effects of exercise therapy.

The study might be a good fit for you if you:

• Are aged ≥ 50 years with knee osteoarthritis.
• Have knee pain for more than 3 months and on most days of the past month.
• Have average pain intensity higher than 4 out 10 in the past week.
• Do not have previous knee joint replacement or high tibial osteotomy.
• Do not knee surgery or joint injection in past 6 months.
• Do not have planned surgery in the next 9 months.
• Do not use oral corticosteroids currently or in the past 4 weeks.
• Do not have systemic arthritis, previous knee fracture or malignancy.
• Do not have other condition affecting lower limb function.
• Do not participate in knee strengthening exercise in past 6 months.
• Do not have a loss of sensation of the affected leg.
• Do not have neurological or psychiatric disorders.
• Do not have contraindications to brain stimulation such as epilepsy, metal implant in the skull.
• Do not use neuroactive drugs.

If you are eligible and agree to participate, you will be asked to attend 2 sessions per week for 6 weeks (each session includes 15 minutes of active or sham brain stimulation plus 30 minutes one-to-one exercise by a physiotherapist); 2 testing sessions (about 1.5 hours per session) before the start and after the completion of the intervention. All sessions will take place in a laboratory at NeuRA.

If you would like more information or are interested in being part of the study, please contact:

Name: Dr Wei-Ju Chang

Email: w.chang@neura.edu.au

Phone: 02 9399 1260

This research is being funded by the ANZMUSC Clinical Trial Network.