Researchers at the Medical Advanced Manufacturing Research Centre have assisted an orthopaedic products company in developing a surgical screw that improves operating procedures for surgeons and outcomes for their patients.
Huddersfield-based Innovate Orthopaedics (IO) develops medical devices that solve problems identified by surgeons in order to achieve better results for patients without increasing costs.
IO asked the Medical AMRC – part of the University of Sheffield Advanced Manufacturing Research Centre with Boeing – to evaluate two new designs it had developed with leading orthopaedic surgeons for specialised orthopaedic screws.
The screws, made from biomedical Titanium alloy TI-6AL-4V ELI (ASTM F 136), are designed for certain surgical procedures, including reconstructing the knee’s anterior cruciate ligament.
Reconstruction is carried out by inserting a piece of healthy tendon in place and securing it to the bone with a screw, over which the bone will grow.
The medical AMRC worked with IO to combine aspects of their two designs and create one universal design that reduced the force needed to insert the screw while maintaining fixation.
Marcus Crossley, from the Medical AMRC, said the new screw helps the surgeon by engaging more rapidly with the ligament and bone when it is inserted, reducing the fatigue experienced by the surgeon and minimising damage to the replacement ligament.
Medical AMRC showed how the universal design could be used to produce a wide range of screw sizes and worked with AMRC partner Star Micronics to develop the CNC program that allowed prototype screws to be produced on a Star Micronics sliding head lathe.
Sandvik Coromant provided the bulk of the tooling, whilst Sheffield Precision Medical carried out trial production runs and developed the complete range of screws.
According to IO founder Alex Gutteridge, clinical tests have produced positive results and demand for the solution is rising among surgeons.