Patch made of your stem cells helps avoid need for a new knee
A PROCEDURE to regrow cartilage using stem cells helps patients avoid knee replacement. Steve Neary, 36, a tree surgeon and landscaper from Winchester, tells
CAROL DAVIS about having it done. THE PATIENT
PlAYING football aged 18, I ran full pelt off the pitch and into a barrier. My body went one way and my lower left leg went the other.
The pain in my knee was agonising. Within minutes, it had swelled to the size of my thigh. My teammates wanted to take me to hospital but I just wanted to go home — it was an away game and I didn’t want to be stuck on the Isle of Wight.
I couldn’t really walk on the leg, but I didn’t see the point of X-rays. I just treated it with ice, elevation and compression, and took four months off football.
But in my first game back, I jumped up for a header and, when I came down, I landed with my left knee locked and felt the joint ‘ pop’ backwards. The pain was unbelievable and I was rushed to A&E.
X-rays showed that I had ripped through my anterior cruciate ligament (ACl), which supports the knee and joins the shin to the thigh bone.
The doctors said the first injury had partially torn it, and the second snapped it completely. I’d also damaged the cartilage covering the joint in these two accidents, and by continuing to work and play sport afterwards.
Doctors said I would need surgery to repair the ACl, which I had six months later.
The operation was successful, but, despite lots of physiotherapy, my knee wouldn’t bend properly. This made climbing trees with a chainsaw very difficult.
It turned out that, while my ACl had recovered, the damaged cartilage was so far gone that I now had arthritis. S
EVERAL years later, I had a microfracture operation, where they drilled tiny holes into the bone to stimulate the cartilage to grow back. But the pain and stiffness remained. I had to take care over which trees I climbed, and I did more landscaping instead.
I saw the same surgeon again four years ago. He offered an osteotomy, where they take a wedge out of the thigh bone, then reset it to change the angle so weight goes through undamaged cartilage. It sounded horrible.
The alternative was a knee replacement, and I was advised that I was far too young for that. They wear out, and ten years down the line I’d need repeat surgery.
By now, I could only play six-aside football.
Chatting to my teammate Gorav one day, he mentioned that he had run a trial to regrow knee cartilage. I hadn’t known he was a consultant orthopaedic surgeon, and I asked my GP for a referral. I saw Gorav at Southampton General Hospital.
He explained that the ABICUS trial treated patients by taking stem cells (which can turn into any cells in the body) from the hip, then processing them in the laboratory there and putting them on to a special patch which goes on to the damaged cartilage to help it regrow. I felt I had nothing to lose. Nine months later, the trial reopened and I had the 25-minute operation in March 2017.
Afterwards, I was put into a leg brace that went from my ankle to two-thirds of the way up my thigh, and my brother-in-law took me home the next day.
It was very painful after the first 24 hours, and I was prescribed a strong painkiller, tramadol.
Over the following months, I had lots of physiotherapy to strengthen the joint as the rigid brace was gradually unlocked — it had locked hinges, which were loosened in stages to give more movement, starting at the ankle.
Three months later, the brace was taken off and, four months after surgery, I was off crutches.
My leg was incredibly weak, but I started with a few landscaping jobs and was back full-time by Christmas that year. Finally, I can use my knee properly again.
I’ve started playing golf, am doing lots of building work on my house, and I’m delighted I won’t need a knee replacement.
WE CAN try microfracture, where we make multiple holes in the bone just beneath the damaged cartilage to prompt bleeding, so scar tissue grows and fills the crater, acting like cartilage. But this tissue is much softer and less long-lasting than natural cartilage.
Another option is autologous chondrocyte implantation, taking cartilage cells from the knee itself and growing them in a lab.
Six weeks later, the patient has a second operation to implant them surgically through a small incision. However, it is expensive — costing the NHS around £17,000 — and not widely performed, since we need a special licence from the Human Tissue Authority.
So we are trying a newer technique using bone marrow-derived stem cells, which involves only one operation, no licence and costs less. It takes around 25 minutes under general anaesthetic.
First, I put a camera into the knee through a tiny incision to check there are no other issues, and then make a 4cm incision over the damaged area.
I use a syringe to draw bone marrow from the hip. A technician then puts this into a centrifuge, a machine which spins the tissue and separates out the stem cells from red blood cells and plasma, until we have 1ml.
Meanwhile, I make holes in the damaged area to prompt bleeding and cut a piece of material called Hyalofast, rather like tissue paper, to fit over the defect and act as a scaffold for new tissue to grow into. We apply the stem cells to this scaffold. Then I close the incision and send the patient to recovery.
This approach produces new cartilage, although only time will tell how successful it truly is.
For young people who don’t want a knee replacement, this is a good option, and results so far show better function and less pain for up to five years compared to microfracture. THE op costs £1,700 to the NHS and up to £7,000 privately.