Len Chandler’s right heel had been hurting so badly that he could barely walk, but the retired builder from Rutherglen in Victoria kept going with the help of orthotics and anti-inflammatories. It wasn’t until he had an MRI that the Australian grandfather realised how serious it really was. “You’re in trouble,” said his doctor. “It’s cancer.”
Referred to orthopaedic surgeon Professor Peter Choong at St Vincent’s Hospital in Melbourne, Len was shown how a rare cancer had eaten a gaping hole in his heel bone. The only option was amputation, Professor Choong explained, since conventional implants cannot support the body’s weight or fit properly with the bones in the foot.
But in late 2014, Professor Choong had an exciting new option: he could literally “print” a new heel bone for Len.
Professor Choong ordered a detailed scan to capture the exact dimensions of Len’s good heel. Technicians at medical device company Anatomics mirrored the scans and created a digital model of Len’s missing right heel bone. This information was sent to experts at the Commonwealth Scientific and Industrial Research Organisation (CSIRO). With a sophisticated 3D printer and titanium “ink”, they set about printing a new heel for Len, layer upon microscopic layer. The revolutionary prosthesis was crafted to the finest detail, with smooth surfaces where it would contact bone, holes for the stitches and rough surfaces to allow tissue to adhere.
A few months after the operation to fit the bespoke heel, Len was driving, walking and playing with his seven grandchildren again.
Printing the future
Scientists developed the first basic 3D printers to replicate solid objects more than three decades ago. Today, printers routinely fashion items as large as furniture and cars, or as delicate as jewellery and microscopic parts. But it’s in healthcare that this technology promises some of the most life-changing applications. Here’s what scientists can do right now and what we can hope to see in the future.
“Bones” are a comparatively easy challenge for 3D printing. With advances in body scanning, it’s possible to map every angle and dimension of existing body parts and then customise a new implant out of plastic or metal (and ceramics, though mostly in dentistry so far), as Professor Choong did with Len’s heel.
Think of it as the difference between a tailor-made suit over one off a rack – the first is made to your exact requirements for the most elegant fit; with a ready-made outfit, invariably the trousers are too long or too short. For years patients and surgeons have been forced to pick the closest fit from the limited range of prostheses available in medical catalogues, but 3D printing allows technicians to make replacement body parts to measure.
In the Netherlands in 2014, a Dutch woman with a rare condition who needed a new skull received a 3D-printed cranium that was made after scanning her head. It was positioned over her brain much like a cycle helmet. Thousands of others around the world have already received customised sections of skull to close gaps left after head surgery. And in world firsts, 3D printing has recently been used to create a fingertip, hand bones, arm, jaw and even the bones for an entire skull in a man who crushed his face after a four-storey fall.
To replace teeth, dental labs take detailed scans and “print” accurate crowns, bridges, models and orthodontic appliances – most without having to wait for a technician to cast the parts. And the day’s not so far off when doctors will be able to print body parts on demand, right there in the operating theatre.
“One day I’ll get a patient with bone cancer, isolate the tumour with a computer, scan the patient’s leg with a CT scanner and then print out the part I need to put back in real time,” says Professor Choong.