On 15 February 2019 approximately 50 delegates from various industries ranging from jewellery manufacturers to academics gathered at Zevenwacht Wine Estate’s conferencing facilities to experience the exciting world of rapid prototyping and additive manufacturing in orthopaedics.
Rapid 3D’s David Bullock hosted the event with presentations delivered by LRS Implants, Rapid 3D and Executive Engineering, with whom LRS Implants has partnered locally to manufacture their custom 3D printed components.
3D printing or additive manufacturing is not really something new, in fact the process, in some form or another, has been around since the early 1970s. Neil Campbell, CEO of LRS Implants, used the analogy of a 1980s Land Cruiser juxtaposed with a Land Cruiser from more recent times – it’s really about the technological advances that have been made since then that have allowed the technology to be embraced more frequently, and used for an ever-increasing number of applications. Simply put – it’s much better now.
Neil Campbell of LRS Implants explains the process of rapid prototyping and additive manufacturing in orthopaedics
While the technology is not limitless, its importance in the world of manufacturing is being recognised more enthusiastically by industry. These advances have come in the form of better materials, better surface treatments and better machining capabilities. The costs associated with the various methods of rapid prototyping have also decreased significantly and the industry is now on the cusp of mass production – two key advantages of this being faster lead times on production runs and manufacturers having reduced inventories by virtue of on-demand replacements, that is, less unnecessary stock taking up valuable warehousing and shop floor space. Long-term, this will have a significant impact on the environment too as it will lead to more materials being recycled and reused.
LRS Implants, headed up by Neil Campbell, is one of South Africa’s leading companies providing a full suite of solutions for both upper and lower limb salvage scenarios. Neil is passionate about finding solutions for any orthopaedic case or problem. He holds an Honours degree in Mechanical Engineering and a Masters degree in Biomedical Engineering, both from the University of Cape Town. He has spent over 10 years in the industry, working closely with leading international orthopaedic surgeons, both in the field of limb salvage and general orthopaedics.
Campbell demonstrated that human bones are living tissue, and thus the technologies of rapid prototyping and additive manufacturing are perfectly suited to the needs of limb salvage – the final step before amputation. A variety of patients could experience the need for some form of limb salvage and these include cancer sufferers, severe trauma sufferers and replacement implant or prosthetic patients. He says that you can design and print anything, but it doesn’t mean that it will work.
Campbell said that it is about offering patients a better quality of life, as opposed to full function. Although in certain instances, and depending on the extent of the component or procedure, very respectable results will be obtained. It’s personalised surgery with patient specific implants.
Willie Conradie of Executive Engineering and David Bullock of Rapid 3D
“The primary goals of both the designer and the surgeon are to reconstruct and recreate the integrity and symmetry of the limb so as to provide the patient with a long-term, functioning and pain-free limb,” he said. Implants are designed and manufactured by LRS Implants and Executive Engineering via the CT DICOM (Digital imaging and communications in medicine) data that is converted into stereolithography (.stl) file format and imported into 3D Computer Aided Design (CAD) software. LRS uses Solidworks. “The models are then used to design a suitable prosthesis, as well as the templates and jigs required for the insertion of the implant,” says Campbell.
“Revision surgery and limb-reconstruction surgery are technically demanding and require careful pre-operative planning in order to achieve accurate bony cuts and correct implant positioning and fixation. With the use of our proprietary CAD software and embracing 3D printing technology, we as a company have advanced consequently,” continued Campbell.
While materials such as stainless steel and cobalt chrome have previously been used, titanium is now the material of choice. Cobalt chrome is notoriously difficult to machine and stainless steel comes with its own problems when used in the human body. Further technological advances such as silver coating the titanium to help prevent infection are being realised, which could have benefits over slow release antibiotics as infection and bugs can be a cause of surgical failure – not the surgery or the implant itself. A further benefit of titanium is its very good fatigue resistance.
Attendees view the EOS M 290 in action on a tour of the Executive Engineering facilities
New research is being undertaken in the field of stem cells to find ways to encourage bone growth, but for now, the mesh structure of the components printed allow perfectly for the regrowth of the bone onto this mesh structure. Prototypes can be designed and taken from x-rays as well as from CT and MRI scans.
In 2018, Executive Engineering installed an EOS M290 Metal 3D Printer in their Cape Town facilities, and together with their customer, LRS Implants, took the lead in local additive manufacturing of orthopaedic implants.
Willie Conradie of Executive Engineering explains their partnership with LRS Implants to locally manufacture components for them:
“We have expanded our prototyping and manufacturing capabilities by investing in an EOS M 290 metal sintering machine, supplied by Rapid 3D. The EOS M 290 is based on the DMLS (Direct Metal Laser Sintering) 3D printing technology developed by EOS. This 3D printing technique uses a fiber laser to melt and fuse fine metal powder. Layer after layer the 3D object is built. This 3D printing method allows us to create 3D printed products with complex geometries including elements such as freeform surfaces, deep slots and/or coolant ducts.”
Campbell explains that as a result, “We now outsource all our manufacturing to Executive Engineering. Partnering with Executive Engineering has freed us up to concentrate on our core competencies of implant design in conjunction with surgeons and academic institutions. The team at Executive Engineering has delivered exemplary quality products, often under tight deadlines. This is born out by their having been awarded the ISO 13485 accreditation for medical manufacture and having a full service machining setup. Machining still needs to take place once the 3D object is built. Logistically it was becoming a nightmare for us and we now have a local partner that can provide us with a full service.”
“We appreciate the fact that they have a can do attitude and have exacting quality standards, and we are exceptionally happy to partner with them going forward to grow our business.”
The EOS M 290 can manufacture multifaceted components
“The addition of the EOS M 290 direct metal laser sintering printer by Executive Engineering opens up huge new possibilities for us going forward, especially in the patient-specific custom implant market. The most fulfilling part of my job is seeing a design move from computer, to machine, to patient, knowing that we have made a difference in that patient’s life.”
This technology and a printer of this magnitude are perfectly suited to industries such as limb salvage and jewellery manufacturing as not only does it produce perfect, customisable components, but it also increases production times rapidly. After the presentations, attendees took a tour of the Executive Engineering facilities where the EOS M 290 is kept and got to see it in action and see first hand the complex components it is capable of manufacturing.
David Bullock says: “We are at the dawn of a new era in flexible production where conventional manufacturing struggles to offer solutions. However, this technology transition can be realised with additive manufacturing (AM) and its ability to enable intelligent components and digitalised production.”
“AM technology is a powerful enabler for innovative South African businesses supporting competition and development in the Global market. Rapid 3D’s event with Executive Engineering, LRS Implants and EOS was attended by more than 50 people from various businesses, and illustrates the interest in the application of the technology,” concluded Bullock.
While the printing of other organs such as ears is already being done in other materials, for now metal remains the best material available. We should expect to see further growth to come in the form of polycarbonate, polyethylene and polypropylene laser sintering in the near future.