How 3D printing is set to revolutionise reconstructive surgery

A decade ago, the idea of 3D printing body parts to seamlessly replace damaged or disfigured limbs, joints and features may have seemed like science fiction. Now, as 3D printing technology stands on the cusp of a new era of combining biosynthetic products with our natural flesh and bone, the way surgeons treat their patients is changing forever. In 2015, American schoolboy Dallan Jannet was the first to receive a 3D-printed nose, at the age of 14, after falling face first on to live electrical cables. Reconstructive surgeons restored his taste and smell with a functional, 3D-printed nose that even matched his pores, skin tone and wrinkles for a more organic feel. Once considered groundbreaking, these techniques first explored by pioneering surgeons have advanced to a degree where patients can now receive perfectly matched custom-fitted prosthetics to replace body parts. Julian Callanan, managing director of Sinterex, established his 3D printing company in 2016 during the embryonic era of the technology in the UAE. A pilot project to work alongside surgeons at the Dubai Health Authority’s Rashid Hospital ended this year and explored new areas of printing prosthetics, tools and surgical guides required for the operating table. Today, the company remains part of the emirate's 3D Printing Strategic Alliance, a platform under the Dubai Future Foundation that pulls together government entities and private companies to accelerate the use of 3D printing across a variety of sectors. Sinterex also now prints 3D prosthetics for Mediclinic hospitals and Cleveland Clinic Abu Dhabi. “The way to think about 3D printing in medicine is that each person is different and this enables mass-customised manufacturing,” said Mr Callanan. “We can make things at scale, which are completely individual and different. “If you are having a knee replacement, the regular artificial joint comes in only four sizes. “So, the patient is fitted to the implant, rather than fitting the implant to the patient — as you can do if it is 3D printed.” Custom-fitted joints and templates for surgery allow doctors to take less time to perform complex procedures, and speed up patient recovery. On average, surgeons reported 25 per cent less time spent in the operating theatre, due to the pre-planning allowed by using 3D printed models. It allows for huge savings, about $3,000 to $4,000 in costs per operation. Printing replacement body parts such as ears, lips or a nose involves photogrammetry, a technique that takes several images from a patient to overlay on to an editable model. The files are then checked alongside MRI data and CT scans of a patient to create a perfect fit. Digital sculptures then use that data to replicate the damaged body tissue so it can be printed and perfectly fitted to the surviving tissue. “[The] benefits of 3D printing custom-made joints for patients are they are generally more suitable, so can be fitted faster, last longer and are generally slightly cheaper as the surgery is shorter,” said Mr Callanan. “Rather than surgeons having to manipulate a joint to fit during surgery, as it is custom built, they know it already perfectly fits. “In one kidney transplant case, the surgeon said after he had reviewed the surgical 3D model, he changed his approach to go into the patient via their back with keyhole surgery, rather than the stomach with a large incision. “There was less damage to stomach tissue so it was better for the patient.” Dental, maxillofacial and orthopaedics are key areas of health care where 3D printing is now used, and can replace bone and teeth using titanium or cobalt materials. They are proven to be biocompatible over a long period of time and do not leech to pollute the body. Titanium is also slightly porous, which allows for oscillo-integration, where natural bone can grow into and through the titanium so it is absorbed into the body. One of those to recently benefit from a new 3D printed knee joint is Mohammad Shafiq, 69, an American in Dubai who had lived with a deformity in his right knee. Mr Shafiq travelled regularly and endured daily pain while walking until doctors at Burjeel Hospital for Advanced Surgery in Dubai created a replacement knee joint that has transformed his life. An X-ray of Mr Shafiq’s knee showed an unusually large bone that would make it difficult to fit a standard prosthetic, so a custom knee joint was printed instead. A CT scan provided the exact dimensions required for the manufacturer in Switzerland, who then created a virtual model and then an implant base. It took three to four weeks for the company to finish the product. “The custom-made implant made it possible to perform a cruciate-retaining surgery,” said Dr Samih Tarabichi, who performed the operation that allowed them to retain more of the patient's ligaments. “We did not have to resect the posterior cruciate ligament during surgery, thereby maintaining the normal structure of the knee. “An implant is like wearing a shirt. If it is not of the proper size, you won’t be comfortable wearing it.” After the complete knee replacement surgery, Mr Shafiq was able to walk about an hour later. Burjeel currently outsources its 3D printing implant operations to Symbios in Switzerland and the UK. Currently, only about 3 per cent of custom implants are 3D printed at the hospital, but that is expected to increase significantly. The hospital aims to have its own 3D printing centre on site within six months, to reduce reliance on overseas printers, which delays patient recovery, said Dr Tarabichi. “It will be a breakthrough for the region,” he said. “When we do this in-house, design and printing, we can be the source for 3D printing in the GCC. “It will save time, from three months down to just a week, and we can ship it to anywhere in the Middle East. “To build this infrastructure with computer ability and engineers in Dubai is doable and really exciting for us.” Reconstructive surgery is another area of specialist care set to greatly benefit from new developments in 3D printing in the years to come. From titanium implants that fit seamlessly into bone, to biomaterials used alongside a patient’s body tissue to reconstruct damage, 3D printing has an important role to play. Dr Demetrius Evriviades, a plastic surgeon at King's College Hospital London Dubai, operated on Pakistani activist Malala Yousafzai to rebuild her face after an assassination attempt by the Taliban on a school bus in the Swat Valley in 2012. Dr Evriviades was one of two reconstructive surgeons who helped wounded soldiers during the worst years of the Taliban insurgency in Afghanistan, rebuilding genitalia damaged by roadside bombs. Now working in the UAE, he is excited about the future potential of 3D printing in his field. “This technology is hugely beneficial in our pre-surgical planning and has become routine in head and neck reconstruction surgeries,” said Dr Evriviades. “We can now print a perfect titanium implant which goes into the bone for amputees. It is completely anchored into the femur of the amputee, so they can then click on a prosthetic limb, terminator style. “That conveys huge functional improvements for an amputee as they no longer have to wear a socket, which causes a lot of problems and discomfort. “We can print a bespoke implant, designed specifically for that patient, based on results from a 3D CT scan. It is like buying a suit off the peg, compared with one that is tailor made.” In patients born without an ear, or who lose one through misfortune, reconstruction is challenging. Now, biological scaffolds can be printed for ear reconstructions to be implanted. It involves harvesting rib cartilage and spending hours carving a scaffold for an ear, securing it with wires, implanting it in the head and then covering it with biological tissue and skin. “We are on the cusp of a new era of tissue engineering,” said Dr Evriviades. “By printing a biological scaffold, you can create a perfect replica of someone’s ear can then be implanted and transferred. It is an exciting development.” Tissue manufacturing is already in place, where bovine collagen and shark fin cartilage are used to generate a new human skin with a silicon layer on top, called Integra. It can be used to make the dermis, the inner layer of the skin beneath the epidermis. The body grows into it, it is vascularised and eventually replaces the bovine collagen and shark collagen with the patient’s own new dermis. It takes a few weeks but it is a way to create new skin, minus the nerve endings and hair follicles. “In reconstruction, if you can take something from elsewhere in the body, it is less likely to be rejected by the body,” said Dr Evriviades. “But that has a cost to the patient, with extra surgery, scarring, pain and morbidity. If we can take a patient’s cells and grow them into more cells to populate them into a structure, that is the holy grail.”

How 3D printing is set to revolutionise reconstructive surgery

From new ears to a perfect knee replacement, what once would have seemed like science fiction is becoming medical fact