Fixing a fracture the ‘idiot-proof ’ way – thanks to 3D printer

SURGEONS are using astonishingly accurate 3D printed bones to help fix severe fractures, speeding up recovery and saving patients from repeat operations – and even amputations. The injured area is scanned using a technique similar to an X-ray, so a computer model of the bone can be created. This is then used to fashion a replica of the fractured bone using a 3D printer, allowing doctors to plan repair procedures beforehand – and making the operation ‘idiot-proof’, according to the British surgeon pioneering the method.

About 35,000 Britons each year suffer a bone fracture that does not heal correctly. Infections, smoking and certain medications are typically to blame. However, it can also happen for unknown reasons.

These fractures lead to long-term pain and disability and can be corrected only through surgery to realign the bone and fix it in place using metal plates and screws.

To achieve perfect alignment, operations often have to be repeated several times, costing the NHS an average of £60,000 per patient a year. In up to ten cases a week, repeated surgery fails, leaving amputation as the only option.

The new technique, developed by a team led by Professor Anan Shetty, director of stem-cell research at Canterbury Christ Church University in Kent, uses a combination of 3D printing and stem-cell therapy.

Doctors take a special type of CT scan of the bone from several angles, which is then used to create a 3D model of the limb on a computer. Often, new bone has grown that needs to be removed, after which a plate is used to fix the bone into the correct position.

Surgeons plan how the operation will be carried out beforehand and what the bone will look like after surgery on the computer screen. A life-size model of the bone postoperation is created using a 3D printer – a special machine that creates ‘sculptures’ by building up thousands of wafer-thin layers of plastic. The team uses this to prepare the steel plate that will hold the bone in place while it heals.

This is normally done during the operation itself, which takes longer and has a higher risk of trauma and blood loss. Using the 3D technology method and fitting the plate on the model beforehand, surgery takes just 30 minutes, compared to several hours needed in previous bonefracture procedures, and many patients go home the same day.

The surgeon cuts away a section of bone to correct the damage, and fixes it in its new position using the plate fitted on the 3D printed model beforehand. To speed up the healing process, Prof Shetty and his team also use stem-cell treatment by taking bone marrow from the patient’s own hip.

After the plate is fitted, a gel made from a mixture of the patient’s own stem cells and collagen is injected into the bone. Prof Shetty’s team take X-rays six weeks after a fracture to monitor healing.

They have now treated eight patients with 85 to 90 per cent success rates – the procedure costs less than £10,000 privately but is not yet available on the NHS.

ANDREW Kent, 60, a bank worker from Gillingham in Kent, was the first Briton to have the pioneering procedure after a falling rock shattered his right leg and foot as he climbed in the Lake District in 2009.

Andrew was airlifted to hospital by the RAF – the medical team warned then that his leg might have to be amputated since his injuries were so severe. He had an operation that day, followed by two more.

Then infection set in. Dr Shetty operated six weeks later once the infection had cleared, but warned that Andrew risked amputation if the leg did not heal.

‘The bones were held in place by metal plates, and it felt very uncomfortable,’ says Andrew. ‘My foot was at a strange angle so I couldn’t walk properly.’

In February, Prof Shetty, a consultant trauma surgeon who treats NHS and private patients at Spire Alexandra Hospital in Chatham, Kent, made a 3D model of Andrew’s leg, reshaping the leg and using stem cells to promote healing.

‘Now I’m back to cycling again, and using my leg normally,’ says Andrew. ‘It’s simply wonderful.’