Active not recruitingNAINTERVENTIONAL

All Polyethylene Versus Metal Backed Tibial Components in Knee Replacement

If you're aged 75 or over and need a knee replacement for arthritis, you might be interested in this study. We're looking at two different types of knee replacement components that fit onto your shin bone. One is the standard metal-backed type, and the other is a newer, all-plastic type that's less expensive to make. Our aim is to find out if the all-plastic component works just as well as the metal-backed one in terms of reducing pain, improving movement, and how long it lasts. By carefully comparing them, we hope to improve future knee replacement care for everyone.

At a glance

Status

Active not recruiting

Phase

Sponsor

Maidstone & Tunbridge Wells NHS Trust

Enrolment target

Start

01 Jan 2017

Estimated completion

01 Jul 2025

Osteoarthritis, Knee

What is this study about?

When you have a total knee replacement, the surgeon replaces the damaged parts of your knee with artificial ones. This is a very common operation that helps many people get rid of pain and move around better. In the UK, thousands of these operations are done every year. We know that good knee replacement designs can last 10 to 15 years or even longer, and patients are usually happier when they recover quickly and can get back to their daily lives soon after surgery.

This study focuses on a specific part of the knee replacement called the 'tibial component', which is the bit that fits onto your shin bone. There are two main types designers use for this part: one with a metal back and another that's made entirely of a special kind of plastic. The all-plastic version is much cheaper to make. Other studies have already suggested that these all-plastic parts are safe and work well, but we want to do our own in-depth comparison.

So, we are inviting people aged 75 and over who are having knee replacement surgery for arthritis to join our study. If you decide to take part, you'll be randomly assigned to receive either the metal-backed or the all-plastic tibial component. We will then follow your progress for up to five years, carefully checking how your knee feels, your pain levels, and how well you can do your daily activities. We'll also take X-rays to see how the replacement parts are positioned and holding up over time. This will help us understand if the cheaper, all-plastic component is just as good, or even better, than the traditional metal-backed one.

Key takeaways

Compares two knee replacement parts: metal-backed vs. all-plastic.
Aimed at patients aged 75 and over with knee arthritis.
Participation involves random assignment to one type of knee part.
Includes follow-up appointments, questionnaires, and X-rays over 5 years.
Helps improve understanding of knee replacement effectiveness.
You can withdraw at any time without affecting your care.

Who may be eligible?

This study is looking for people aged 75 or older who are having their knee replacement for the first time because of arthritis. You should be able to walk by yourself, understand the study information, and be willing to come for follow-up appointments.

There are some reasons why you might not be able to join. For example, if you've had previous knee surgery (apart from some minor keyhole or open procedures), if you have other serious health problems, if you have conditions that make it hard to walk properly, or if you can't give your consent to take part due to severe visual impairment or other reasons.

Could this study suit you?

Answer these quick questions to see if you may be eligible. This is a guide only — the research team makes the final call.

Are you 75 years old or older?
Are you having your first knee replacement for arthritis?
Can you walk on your own (even if with aids)?
Do you feel you can understand the study information and attend follow-up visits?
Have you NOT had previous major knee surgery (besides specific minor procedures)?

Answer every question to see your result.

What does participation involve?

If you are interested in this study, you'll first receive an information sheet to read through and ask any questions you might have. Before your operation, you'll come to a special clinic where the study will be explained in person, and you'll have another chance to ask questions and decide if you want to take part. If you agree, you'll complete some questionnaires about your knee and how you're feeling.

After your knee replacement, you'll have standard check-up appointments at 6 weeks and 3 months. Then, your study follow-up appointments will be at 1 year, 2 years, and 5 years after your surgery. At these appointments, your knee will be checked by a doctor, and you'll complete the same set of questionnaires you did before the operation. We'll also take X-rays of your knee to see how the replacement is doing. This means a few extra appointments over five years, but it's important for understanding how well the knee replacements work over time.

Potential risks and benefits

Taking part in this study means you could be helping us learn important information that might improve future knee replacement surgery for many people. You'll receive careful monitoring of your knee replacement over several years. There are no known extra risks from being in this study beyond those associated with standard knee replacement surgery and follow-up appointments, which include some extra visits to the hospital and X-rays. You are free to withdraw from the study at any time without giving a reason, and this will not affect the normal care you receive.

Locations (1)

Some site locations are approximate. We're improving this — please verify with the trial team before travelling.

Trauma & Orthopaedic Dept, Tunbridge Wells Hospital
Verified postcode
Pembury, United Kingdom

Common questions

What's the main purpose of this study?

To compare two types of knee replacement parts in older patients to see which works best over time.

Who can join this study?

People aged 75 and over who are having their first knee replacement for arthritis and can walk.

Will I get to choose which knee part I receive?

No, the type of knee part you receive (metal-backed or all-plastic) will be chosen randomly, like flipping a coin.

How long will I be involved in the study?

You will be followed for up to 5 years after your knee replacement surgery, with a few extra follow-up appointments.

Can I leave the study if I change my mind?

Yes, you can withdraw from the study at any time, and it won't affect your treatment.