Donor transplant that could repair your creaky knee

KNEE replacement surgery is generally unsuitable for people under 50 but Jason Bear, 46, an IT specialist from Hemel Hempstead in Hertfordshire, underwent a new procedure, as he tells LEAH HARDY.

THE PATIENT

SporT had always been something I loved doing, and I used to play football semi-professionally. even at 43, my life outside work still revolved around sport. But one week in January 2013 I played football one day, and squash the next, then woke up in the morning to find my right knee had ballooned and I couldn’t bend my leg.

I took ibuprofen so I could hobble to work, but after five days I still had stabbing pains in my knee when I tried to walk.

I had private health insurance so my Gp referred me to an orthopaedic surgeon, and two weeks later I had an arthroscopy, where they use a tiny camera to look inside and repair the joint.

The surgeon said I’d so badly torn my medial meniscus, a cushion-like pad in the knee that acts like a shock absorber, he had to take out almost the entire thing.

He thought I had probably torn it when I’d badly twisted my knee during a match 15 years before.

Because it had been damaged for so long, the smooth cartilage over the end of my thigh bone, known as articular cartilage, had worn away, leaving bare bone, meaning that I had premature arthritis.

I was also bow-legged, as the cartilage loss had put additional pressure on my inner knee. y surgeon referred me to a knee specialist, Ian McDermott, who said that if I was older I would be offered a knee replacement.

But in young and active people they last less than 15years. you then need a new implant but because there is less bone to attach the replacement joint to, these operations have twice the rate of complications.

Most people are told to limp on and take painkillers until they are in their 50s. But I was in pain and without regular exercise I get down.

Mr McDermott suggested a new operation called a biological knee replacement, where I’d get a meniscus transplant from a dead human donor and a treatment to regrow cartilage over the end of my thigh bone. I’d also have surgery to straighten my bow leg.

My biological knee could last up to 20 years. Then, as none of my bone had been removed, a conventional knee replacement would be uncomplicated.

I was apprehensive. It would take at least six months for me to recover — but I went ahead. The operation, in November 2014, took nearly four hours.

When I came round I felt fine, as I was on continuous intravenous pain relief. But when I left hospital three days later the pain really kicked in.

My knee was dark purple with bruising and very swollen, and in a knee brace which made it very hard to walk.

I couldn’t manage stairs, so I slept on the sofa. It was three months before I could walk without crutches and the brace was removed. Then I worked with a physiotherapist to strengthen my muscles. Two years on, I go to the gym every day for an hour and have no pain at all.

THE SURGEON

ian McDerMott is a consultant orthopaedic surgeon at London Sports orthopaedics clinic. THere are two types of cartilage in the knee: articular, the smooth layer that covers the ends of bones, reducing friction, and meniscal, found within the joint, that acts as a shock absorber.

Both types are prone to wear and tear, but if the meniscal cartilage is torn or removed, pressure on the articular cartilage increases and can speed up the onset of osteoarthritis — when bone rubs against bone.

Meniscal tears are common and are often caused by patients twisting a knee playing sport, but can occur in everyday life in older people, especially as their meniscus is thinner.

Some tears heal without treatment, but most are treated by removing or ‘trimming’ the rough, damaged portion, allowing the remainder to heal. Unfortunately, this leaves less cushioning in the joint, and in time, the bones lose their protective articular cartilage.

Until recently, most surgeons would not try to restore the missing articular cartilage (by drilling tiny holes in the bone to release stem cells to encourage cartilage to grow) if the meniscal cartilage in that knee was also missing.

That’s because the lack of cushioning would mean the new cartilage would be eroded. Nor would they perform a meniscal transplant if there was bare bone, because this would wear away the transplanted meniscus.

A biological knee replacement allows us to replace both at once. It is intended for patients under 50 — older patients heal more slowly, so the graft is less likely to be successful.

Jason was very keen to start exercising again, and a biological knee replacement was the best option for him.

He HAD the operation under general anaesthetic.

I made three incisions around the front of the knee, ranging from 5mm to 1.5cm, and using a tiny camera as a guide, I transplanted a C-shaped wedge of donor meniscus matched to the size of Jason’s knee.

The graft was inserted through the 1.5cm incision, then stitched to the bone.

To replace the missing articular cartilage, I applied a scaffold of a biodegradable sponge-like material. I made tiny holes in the bone to allow stem cell-rich blood from the bone marrow to soak into the scaffold.

I then covered the scaffold with a biological ‘glue’ made of the sticky part of blood, called fibrin, and platelets (blood cells), which are rich in growth factors. This would encourage the growth of new cartilage into the scaffold. The scaffold dissolves over six months.

Finally, I performed an osteotomy to straighten Jason’s leg by cutting into the lower leg (tibia) bone and fixing it with a metal plate and screws.

a bioLogicaL knee replacement and osteotomy costs £20,000 to £25,000 privately. Meniscal transplants cost the nHS £3,500, while transplants similar to the one Jason had cost over £12,000. Some nHS trusts do not fund them.