A pioneering invention that can accurately measure patients for hip replacements has been developed by the University of Warwick and University Hospitals Coventry and Warwickshire (UHCW).

The device, called KingMark, will see its commercial launch in the US this month. It will be manufactured and distributed by the orthopaedic specialists Voyant Health, following a deal negotiated by Warwick Ventures, the University of Warwick’s technology transfer office.

KingMark, developed by UHCW orthopaedic surgeon Mr Richard King in collaboration with Professor Damian Griffin at the University’s Warwick Medical School, provides a non-intrusive, reliable method of calculating radiographic hip magnification.

Current initial estimation of replacement hip size is correct in only around 30% of cases, so this invention could drastically improve efficiency for orthopaedic surgeons worldwide.

The invention includes a simple kit for measurement and comprises a pad with an incorporated measurement system which is placed face down; the patient lies with their hips on the pad; a string of five linked precision balls are placed on the patient’s abdomen. The anterior (ball) and posterior measurements from the radiograph are entered and calculated and an accurate value for magnification is then generated.

KingMark will become part of Voyant Health’s solutions package for orthopaedic surgeons and will be marketed to the healthcare profession worldwide following its US launch.

Professor of Trauma and Orthopaedic Surgery at Warwick Medical School, Professor Damian Griffin said: “KingMark has removed all of the uncertainty about scaling digital radiographs for hip replacement. Our radiographers find it easy to use, and I can be confident that the measurements I make on scaled radiographs are correct. It is now unusual for my pre-operative templating not to be exactly right.”

More reliable measurement would lead to much less wastage and more efficiency and time savings for orthopaedic surgeons. The invention may also have potential for spinal work and trauma implants as well as other joint replacement operations and any surgery where magnification issues exist.