What you need to know about cell therapy and how it can treat your knee

Written by: Professor Paul Lee
Published: | Updated: 26/02/2020
Edited by: Cal Murphy

Traditionally, we’ve treated serious knee injuries and osteoarthritis with surgical techniques, including replacing the knee entirely. But what if this could be avoided? What if you could find a way to regenerate the knee? Cell therapy is an exciting form of therapy that promises just this. Expert orthopaedic surgeon and sports medicine specialist Professor Paul Lee explains what you need to know:

What is cell therapy?

Cell therapy is a type of biological treatment using the body’s own building blocks to regenerate and regrow an injured part. When part of the body is damaged, cell therapy techniques can help restore that part to its “original” state.

The problem with the human body is that we don’t always recover fully from injuries. Broken bones can heal and bruises eventually go away, but when you cut yourself badly you’re left with a scar that never completely vanishes. Then there are a whole range of injuries that involve the soft tissues of our body – the cartilage and tendons – such as a shoulder injury or knee injury. Even with the best surgery you’re likely to still have limited range of movement and possibly pain. There seems to be something that stops these soft tissues from healing properly.

But what if we could help the soft tissues recover?

That’s what cell therapy is all about. Over the last 40 years researchers have been figuring out the environment our bodies need to help soft tissues grow and regenerate. The latest techniques are safer than ever – and they can be carried out in a single session.

What can cell therapy be used for?

In the knee, typically cell therapy is used to treat a large cartilage defect. It is also possible to use cells to enhance meniscus repair.

With recent advances in technology and experience, we are also now able to treat osteoarthritis, and in some cases, ACL injuries.

The advantages of cell therapy

To understand why cell therapy is so exciting, we need to look at the limitations of current treatments.

When you injure your knee badly, or when you develop a condition like osteoarthritis, there are two main treatment options. Firstly, we have steroids. Steroids are brilliant at reducing inflammation – your body’s natural reaction to injury – and relieving pain. However, they actually damage the cells in your knee, and over time your knee is likely to get worse. When steroids eventually run their course, the other treatment option is surgery – a knee replacement.

It’s true that knee replacements are much better than they used to be. Techniques have improved dramatically over the last few years meaning the surgery is safer and more predictable. The latest generation of knee replacements can be 3D-printed to fit your knee, guided with incredible precision using robotic technology, and made from materials that last for 20 years. The problem is that 20 years is not a long time if you’ve injured yourself at a young age and you have another 60 or 80 years ahead of you.

We know that a biological solution is the only option that can stand the test of time. No matter how sophisticated surgery becomes, nothing is as tailor-made for our own body as the knee we already have. The best thing to do is to use our own body to heal ourselves – and that’s the ultimate promise of cell therapy.

How does cell therapy work?

Cell therapy is often misunderstood as just a series of injections. While cell therapy certainly does involve injections, it’s much more than that.

The best way to think about cell therapy is to imagine that you’re repairing a patch of your garden. There is a patch of dead grass (the damaged cartilage in your knee) that you’d like to repair. If you just threw some seeds on top of the dead grass, this would be a bad idea. You need to remove the bad grass, get rid of the weeds, dig up the dry soil and put some new soil down. The seeds you scatter then need plenty of water and sunlight to grow.

Similarly, in the knee, there are several steps to the process. Diseased tissues need to be removed, the foundation needs to be rebuilt, external harmful forces need to be corrected, and proper nutrition and cells are also needed to enable the cell therapy process to happen. Eventually, new cartilage will grow and thrive in a healthy environment.

So cell therapy is a combination of therapies:

  • Hyaluronic acid – a man-made molecule that can improve the environment around the damaged cells and give them the nutrients they need to help them recover.
  • Stem cell therapy – the “seeds” we inject into the knee that can turn into healthy cartilage
  • Growth factors such as PRP – these enhance the growth of the stem cells
  • Scaffolding – a living transplant made from your own cartilage cells that provides the structure you need in your knee

What’s the evidence that cell therapy works?

There is different evidence out there for cell therapy. It depends what we are looking at. In some sectors of cell therapy, there are over 20 years of experience and many randomised control trials to show that it is superior compared to traditional treatments, for example, micro-fracture. There are also studies that suggest it makes no difference.

This variety is to be expected in a field that has evolved so much over time. Inevitably there will be techniques that do not work, and situations where a technique was applied without understanding if it was right for that particular patient.

So to maximise your chances of success, it’s important to do your research, understand the studies relevant to you, and if in doubt, seek professional advice. Simply typing ‘cell therapy’ into a search engine will come up with a lot of unorganised – and mostly irrelevant – facts.

Where should I go for treatment?

Surgical cell therapy requires sub-specialist expertise. It is not something that can be done with a simple injection. In order to correct the environment, your surgeon needs to do the ground work and plan the cells’ recovery. All in all, extensive investigation is needed prior to treatment. Due to the complex nature, you will need a team to help you before, during and after the surgery. I would recommend spending a little time to research into each surgeon you find, as well as their team, to know their background before embarking on your cell therapy journey.

The good news is that there are now more cell therapy specialists in the UK than ever – so there are plenty of options to choose from.

To book a consultation with Professor Lee and explore cell therapy as a treatment option, click here.

Professor Paul Lee

By Professor Paul Lee
Sports medicine

Professor Paul Lee is a consultant orthopaedic surgeon practising in Lincoln, Nottingham, and Leicester. Specialising in sport and regenerative surgery, he treats sports injuries using cutting-edge regenerative techniques such as stem cell treatment and PRP (platelet-rich plasma). He also has expertise in orthopaedic surgery, such as hip replacements and knee problems.

After receiving his medical degree from the University of Cardiff, Wales, Professor Lee continued with higher surgical training, becoming a certified Member of the Faculty of Sports and Exercise Medicine (MFSEM) and Fellow in the European (FEBOT) and UK (FRCS) Trauma and Orthopaedics boards. He completed a PhD in medical engineering and has conducted research into regenerative medicine, which has helped him to treat sports injuries, including a number of UK Premiership footballers. He is now Medical Director of MSK Doctors and he continues to develop new treatments at the cutting edge of his field in his capacity as Director of Research and Cell Therapy Lead for the Lincolnshire NHS trust.

Professor Lee is an experienced orthopaedic surgeon too. Learn more about his orthopaedic surgery experience here.


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