A new magnetic rod could end the pain of knee arthritis without the need for a joint replacement. Steve Broatch, 61, a window cleaner from Carlisle, Cumbria, had the operation and tells Carol Davis his story.
THE PATIENT
Living close to the English Lakes, I’ve always loved trail running and rock climbing, as well as long bike rides and football. But for years my left knee gave me trouble. It ached from time to time, but because the pain came and went I didn’t bother seeing a GP.
A new magnetic rod could end the pain of knee arthritis without the need for a joint replacement
But two years ago I was climbing steps in a customer’s garden when suddenly the inside of my left knee felt as if someone was sticking hot pokers in it.
The pain didn’t ease overnight so I saw my GP who sent me for physiotherapy. But after weeks of this I was no better. I was in constant agony, and could barely walk — I had to use crutches to get about.
I went back to my GP who referred me to a specialist: X-rays showed I had osteoarthritis, meaning the cartilage in my left knee had worn away and bone was now grinding on bone.
The surgeon said it could have been caused by torn cartilage I’d had eight years before — the surgery I’d had then trimmed it rather than mended it.
There are around 95,000 knee replacements carried out annually in the UK due to osteoarthritis
He said the traditional treatment was a knee replacement, but I knew that an artificial knee wouldn’t work as well as my own.
Then he explained that he was taking part in a trial for a new technique where, rather than replacing the knee joint, they altered the way weight was put through it.
He would do this by making a small cut in the bone under my knee. A rod would be inserted, and using a remote control this could be used to widen the cut slowly into a wedge shape.
This would realign my knee so the damaged section would no longer take the strain. Bone would then naturally grow into this gap.
I would have to extend the rod at home using a remote control but to me anything that saved me from having a replacement knee sounded great!
Three months later, I had the operation. By then I limped when I walked. I needed painkillers every day and a knee brace for support.I had to employ someone to go up ladders and clean windows for me.
I had the one-hour operation at Carlisle Infirmary in November 2015. I was given a general anaesthetic and there was no pain when I woke, though I couldn’t put weight on the knee and it was bandaged. I went home the next day with crutches.
Three days later, I started adjusting the rod. There was a staple just below my knee where I had to centre the remote control, which looked like a pair of binoculars.
I’d put the remote control over the staple and switch it on. I couldn’t feel a thing, and it beeped once its preset cycle had finished.
I did it twice a day for under two minutes for ten days, and then went back to hospital to get the rod checked.
After three weeks I could walk without crutches and six weeks later I was climbing ladders.
The following April, I did the 210-mile coast-to-coast Southern Upland Way walk and now I’m back rock climbing and hill walking.
I go for long bike rides with my four children and seven grandchildren, and I’m told my knee pain could be gone for good.
THE SURGEON
Matt Dawson is a consultant specialist knee surgeon at North Cumbria University Hospitals NHS Trust and BMI The Lancaster Hospital.
There are around 95,000 knee replacements carried out annually in the UK due to osteoarthritis.
In 80 per cent of cases, the wear to the cartilage is on the inside of the knee where the body’s load falls naturally — this can make walking and everyday tasks very difficult. Patients can take painkillers, support the knee with braces, or have steroid anti-inflammatory injections.
As the pain worsens, many are offered a knee replacement.
However, we know that patients under 58 are likely to need revision surgery in time as the prosthesis tends to loosen and wear out and that is a bigger operation.
So many patients who have early osteoarthritis simply live with the pain, become less active and may have to give up work.
But I am currently involved with a large European trial for a new device, OptiLine, which was developed in the U.S. around three years ago. It can keep patients active and delay the need for a knee replacement, or do away with the need for one altogether.
It involves making a horizontal cut in the bone just under the knee. At the same time, we insert a long rod into the tibia or shin bone. This is gradually expanded in the weeks after the operation to expand the original straight cut into a wedge shape.
As a result that side of the tibia rises. This means the weight falls through the outer healthy part of the knee, not the arthritic part.
Surgeons have long taken weight off the damaged section of the knee by making a cut through the tibia — known as an osteotomy — and inserting a wedge of bone graft so the weight shifts away from the damaged section.
The tibia is then fixed in its new position using a plate and screws, but this means estimating the correct angle the knee should be in theatre and it can’t be changed afterwards.
Because with the OptiLine we adjust the rod gradually (it extends a bit like a telescope), we can adjust the knee to the exact degree we want it, rather than doing it all at once in theatre using a plate and screws. Also as we gradually expand the cut, bone grows naturally to fill it as the damaged area repairs itself. We take X-rays and use sophisticated software planning beforehand so we know just how far we want to alter the knee.
The operation takes around an hour under general anaesthetic. First we bend the knee and make a 6cm (2.4in) incision under the knee cap, exposing the top of the shin bone. Then I use a pointed instrument called an awl to puncture the top of the tibia and insert a guidewire and a drill to open up a space for the rod. I insert the rod and then secure it into the knee with screws.
The titanium rod is around 20cm (8in) long and 8mm (0.3in) in diameter. Inside it is a clever screw mechanism that activates powerful magnets within the remote control to lengthen the rod.
We check the mechanism works using the remote control, and close the wound with stitches. The patient expands the rod at home using the remote control provided.
Most patients need 9mm to 10mm (about 0.4in) of expansion, which we would achieve over a couple of weeks in around four sessions a day.
We see them six and then ten weeks later for a check-up, and can fine-tune the positioning to our pre-planning at those check-ups.
The rod is normally in place permanently, but we can remove it if it starts causing problems. Sometimes metal implants can cause irritation and minor discomfort in the surrounding soft tissues.
In patients with plates, between 50 to 100 per cent need them removing while only 15 per cent of the rods require removal.
Patients such as Steve should never need a knee replacement as long as we catch this early enough, because we shift the load away from the damaged section.
The operation costs £9,000 to £10,000 privately and to the NHS.