INNOVATION PROFILE: X-Bolt

IT’S HARD TO find an accurate description to sum up Dr Brian Thornes. He’s an orthopaedic surgeon, an entrepreneur, an inventor and an innovator who has combined his medical career with a knack for coming up with novel solutions for bone-injury problems. His first invention, the TightRope for the treatment of ankle fractures, is about to be used for the 100,000th time worldwide while his latest, the X-Bolt, is already in use in several Irish hospitals and has won an Irish Times Innovation Award.

His inventions tend to have been inspired by personal experience. “Back in 1990, while I was a medical student I had an accident while water skiing,” he recalls. “I was run over by a speedboat and the propeller cut my foot in two places – the ankle and further down the foot towards the toes. I always had an interest in ankle injuries after the accident.”

One of the issues in relation to many ankle fractures is the necessity to have two operations. “I always thought it was ridiculous to have two operations for an ankle fracture – one to put a screw in and the other to take it out. With the TightRope, that doesn’t have to be necessary. In some cases, it is taken out but in many cases it stays in.”

The ankle syndesmosis TightRope, to give it its proper name, works like an internal cuff-link, pulled tight, to provide flexible but strong support between the tibia and fibula in high-energy ankle fractures. The problem with using a screw in such injuries is that it is not flexible and doesn’t allow the ankle to move properly.

“I thought about the problem and broke it down into its basic mechanisms,” Thornes explains. “The bones need to be able to move as you walk but an old fashioned screw doesn’t allow for that. A screw will eventually break under the stresses it is put under. The TightRope is a semi-flexible implant which is not elastic but still allows movement. It is a bit like a car seatbelt. When tension goes through it, it doesn’t budge. But a seatbelt allows for some limited movement and that’s what the TightRope does. That means it can stay in permanently although it’s a very simple procedure if it needs to be taken out.”

He came up with the initial concept of the TightRope in 2000 and licensed it to US multinational Arthrex in 2003. Four years later he came up with the idea of the X-Bolt through much the same process. “It was very much the same principles”, says Thornes. “I identified a problem, broke it down to its basic elements, and developed a solution.”

The X-Bolt will improve the efficacy of current hip-fracture treatment and has the potential to reduce dramatically the requirement for very costly and often devastating repeat surgery. It is a novel expanding-bolt device for use in bone fixation in osteoporotic hip fractures. Traditional internal fixation uses bone screws that depend on the hold of the screw threads. The X-Bolt can be likened to a masonry or plasterboard rawl-plug bolt that expands to anchor within the bone, and thus gives a much stronger hold and rotational stability.

Most inventions have their Eureka moment, and while the TightRope’s was a serious waterskiing accident, the X-Bolt’s was altogether more prosaic. “I got the idea for the X-Bolt when I was putting up my plasma TV on the wall of my apartment a few years ago,” says Thornes. “You needed expanding rawl plugs to fix it to the plasterboard wall. Many elderly people’s bones are soft and crumbly and this makes them similar to plasterboard in consistency and causes fixation problems for traditional screws. I set up the company to develop the X-Bolt in 2007 and spent the next few years on its research and development.”

The X-Bolt has been granted a European Patent (EP 2175790) and is patent-pending in the US (No. 12/667,513). Biomechanical data from testing performed in Trinity College Dublin, the University of Limerick, Tallaght IT and Queens University Belfast, has allowed regulatory approval by British Standards Institute (BSI) to award the CE Mark for the device and instrument sets for clinical use.

Some 2,500 hip fractures are fixed each year in Ireland, mostly in elderly patients. Around 5 per cent will require a second operation owing to loss of screw fixation or cut-out. The additional costs associated with cut-out from the additional surgery and prolonged hospital stay are estimated at €4 million per annum in Ireland alone.

The first patient was successfully treated with the X-Bolt on November 29th, 2011, and it is expected that at least 25 per cent of Irish acute hospitals will stock the X-Bolt by the end of the year.

“Like most innovations, the X-Bolt is based on a very simple idea,” says Thornes. “It addresses a huge unmet need in orthopaedic surgery – the problem of fixation in osteoporotic bone. Hip fractures are increasing with enhanced life expectancy and bone quality reduces with age. Hip fractures are a huge and increasing burden and cost on health services. The problem is that screws don’t hold particularly well in soft bone.”

The rawl-plug analogy is an apt one in these circumstances. As people grow older, their bone tissue becomes crumbly resulting in reduced strength and difficulties in terms of fixing fractures.

With European approval already in place, the product is near to final approval by the FDA in the US. The plan now is to gain wide acceptance for the device. “The plan is to increase its use so that we get more clinical data. We are in two hospitals in Ireland at the moment and we hope to be in two more shortly. We have 10 cases of it in use and the next stage is for us to get more clinical use which can be published in the medical literature. A lot of surgeons won’t use new technologies until they see them in use already so we are dependent on the early adopters. Every new medical technology has to go through this stage.”

He points out that the X-Bolt is reasonably easy for surgeons to adopt as it is just part of the kit they use when treating hip fractures. “It’s just a small part of it, 90 per cent of the kit is the same as that already used. It’s as easy or even a little easier and quicker than what they are already doing.”

Unsurprisingly, he is not stopping at the X-Bolt. “We are looking to expand the technology to cover the whole femur,” he says. “Also, we are looking at ways to use the X-Bolt instrumentation for the treatment of other bone traumas such as broken femur. The CE approval we already have allows us to use the technology for fracture-fixation devices and we are anxious to exploit that.”

And he is very proud of the Irish provenance of the X-Bolt. “The X-Bolt was invented in Ireland, developed in Ireland and tested in universities in Ireland. I’m very pleased to be able to say that the X-Bolt is manufactured in Galway, packaged in Ireland and will be distributed and exported from Ireland. We employ between 15 and 20 people indirectly in factories in the west of Ireland and we hope to see this number grow over time.”