Every pelvis is unique, so, if off-the-shelf implants are used during a hip replacement, it can leave people with one leg shorter and less mobile. They are also the most difficult bones to access and fix, explains Orthopaedic surgeon, Dr Andre Olivier. The problem with a pelvis is the 3D anatomy. It is complicated to reconstruct as it differs from patient to patient, even more so when there is a significant defect for either a tumour patient or a patient who has had 3 to 4 previous operations leaving a gap in the anatomy of the pelvis.
Fortunately, South African engineers and designers like UCT Biomechanical engineer Prof George Vicatos had a breakthrough and came up with a revolutionary solution, changing people’s lives one at a time. Born from his love of anatomy and his excellence in engineering, Prof Vicatos ensures implants are able to handle the stresses and strains that bones endure. The implants are 3D printed out of medical titanium at the Centre of Rapid Prototyping and Manufacturing in Bloemfontein. In just over 2 weeks, Orthopaedic surgeons are able to operate with these individualised implants, transforming the lives of their patients.
An engineer can not just design an implant and expect a surgeon to insert it. They must create something that can bypass all the structures, which is the most difficult part. Once engineers have received the CT Scans of the patient, they design an implant that is the exact replica of the patient’s own bone, taking into account where the surgeon wants to attach the implant. From the scan, designers will mirror the healthy side of the pelvis, creating symmetry of the hip. The implant is therefore designed from the structure of the healthy part of the pelvis. These specifically designed implants functions very quickly within the patient, allowing them to live a full life once more.
One of the most critical aspects of the engineer’s design is a jig which shows the surgeon exactly where he decided to cut and where to anchor the implant. This enables the surgeon to position the implant precisely, allowing them to pin and cut the pelvis exactly as one needs to. It is near impossible to do such an operation successfully and reliably without such a jig.
“It is remarkable that options became available in South Africa as opposed to importing implants from abroad. This also eliminates customs clearance issues, but most importantly, saves valuable time for patients who are in desperate need of surgery and relief of pain” – Dr Andre Olivier.