Innovation
Orthopedic surgeon Dr Andre Olivier has joined forces with University of Cape Town Emeritus Professor George Vicatos, founder of Advanced Tumour and Trauma Reconstructive Implants (ATTRI), to offer orthopaedic oncology patients unprecedented quality of life.
It wasn’t long ago that the only choice open to many patients suffering from bone cancer was amputation; a drastic solution that would have a permanent impact on their quality of life.
Dr Andre Olivier, an orthopaedic surgeon at Mediclinic Vergelegen, says the introduction of customisable megaprostheses has changed this. It’s now possible for patients to enjoy life, if not exactly as it was, then with a great deal more comfort, dignity and hope – and that, after all, is a key part of the oncologist’s job.
“As an orthopaedic surgeon, I see many patients besides those suffering from cancer, but I often treat patients who have either primary bone cancer or whose disease has metastasised,” Dr Olivier explains. Treatment may take the form of excising a tumour or fixing a fracture caused by the growth of a tumour. “Complications arise because the bone quality of patients typically degenerates to the point where we can’t use normal plates to fix a bone. The only course of action is to replace it with a megaprosthesis; an implant that’s both large and long enough to replace an entire bone, rather than a small segment.”
It is possible to purchase sizeable prostheses “off the shelf”, but at times it’s necessary to customise the implant – especially when it’s intended to replace the soft tissue that must be removed when a tumour is excised. This is important, as the limb would otherwise lose functionality.
This is where UCT Emeritus Professor George Vicatos’ ATTRI plays a role. Professor Vicatos, whose mother was a doctor, says from an early age he developed a habit of browsing her reference books, which helped him build a solid understanding of anatomy. He harnessed this knowledge when he first started designing devices back in 1992, and 10 years later became a founder of ISIQU Orthopaedics, designing and manufacturing custom implants. He advanced this work at ATTRI (founded in 2012), developing a system of modular implants for arms and legs that can be fully customised to a patient’s needs.
Although customisable megaprostheses aren’t new, Professor Vicatos says their use has gained momentum since the advent of 3D printing. “I became the first person to design and use printed implants in 2007,” he adds. “South Africa started making them through the University of Bloemfontein (CRPM) two years earlier, but these were at an experimental stage. Bloemfontein continues to stand out in this area and is considered one of the best facilities in the Southern Hemisphere.”
It’s easy to understand why customisable implants are in demand: they offer high resolution and are simple to manufacture through a process that leaves no waste material. But perhaps more importantly, printing can produce complex shapes that would otherwise be impossible to produce; think of the intricate forms of structures like the pelvis, ankle or scapular, for example. Professor Vicatos notes that porous structures can be printed as an integral part of the implant, speeding up the integration of devices at resection areas.
Both he and Dr Olivier are excited about the positive impact these implants have on patients’ lives – and, they say, further improvements are certain to come about as the field develops. “It’s not only cancer patients who are benefiting – people who have undergone surgeries like hip replacements also enjoy better quality of life when they have a customised implant fitted,” Dr Olivier reports.
Professor Vicatos, a recipient of the 2022 ARGO-Brussels Hellenic Network Award for his innovative work in biomedical design, agrees. “This is just the beginning. Currently, most implants are made from a titanium alloy because of its biocompatibility, low density, exceptional strength and elasticity. But we in the field are continuously discussing our learnings and experiences, and this is leading to the use of new materials. Polyethylene-keton-keton (PEKK) is a case in point – it’s even lighter than titanium alloy, its flexibility is almost comparable to bone, and its osseointegration ability is also an improvement. Plus, it can be 3D-printed and offers high strength in static loading.
“We have no way of knowing what implants will look like in future, but as we make improvements, we advance the field – step by step.”