Personalised hip implants and surgical planning
It’s a fresh autumn morning when I venture out to Stanmore to visit the Royal National Orthopaedic Hospital. I’m meeting Johann Henckel, an orthopaedic surgeon, who works with Anna Di Laura, a bioengineer in UCL Mechanical Engineering, and their team of engineering researchers at the Institute of Orthopaedics and Musculoskeletal Science. Nestled away in a leafy campus, the team’s office makes a nice change from the hustle and bustle of Gower Street.
The Royal National Orthopaedic Hospital (RNOH) is a UCL-affiliated teaching hospital, globally renowned for its neuro-musculoskeletal patient care and research. Clinicians and scientists at RNOH are pioneering new treatments and technologies for a range of conditions affecting joints, ligaments, muscles, nerves and tendons.
Johann and Anna are interested in the ways robotics and imaging software can help surgeons better plan and perform hip replacement surgery – a procedure performed approximately 1.5 million times a year globally, with about 100,000 of these procedures being done in the UK.
Stepping into the Institute, I am met by an incredible display of surgical objects – from 3D-printed pelvic bones to purple ceramic hip joints. The effect is pleasingly aesthetic. (Who knew orthopaedics could be so pretty?).
Of course, looking great is not the primary purpose. Every person’s anatomy is different, and so each surgical plan must be unique and tailored to the individual’s hip. When things don’t go to plan – for example, the implant rubs against the pelvis, or it degrades at an accelerated rate – surgeons perform what is called a revision surgery. That is what Johann and Anna’s team are working to reduce. They want to minimise complications and make sure that hip replacements last as long as possible.
PhD students Angelika Ramesh and Xing Lim give me the lowdown. They’re using medical imaging and imaging software to improve surgical planning. Using CT scans, they’re able to build 3D digital templates of a patient’s anatomy, helping them accurately plan the orientation, design and size of the implant. Hip implants slot into a cavity in the femur and the pelvis, and with a well-fitting implant, over time the bone will grow up into the implant to keep it stable.
Angelika describes how 3D printing has revolutionised the way hip implants are made, as well as personalised planning instruments, such as perfectly tailored guides which help the surgeon make an incision in the right spot, or the best place to insert a screw.
Xing (who is on Day 2 of her PhD), explains that CT scans are done with the patient lying down, so the patient’s pelvis will be tilted in a particular direction, which isn’t reflective of their daily activity.
“We only spend eight hours a day sleeping. Most of the time we’re moving around, and that’s when dislocation is most likely to happen”.
“We need to ensure that the hip implant position is optimal for how we spend a big part of our time – otherwise it will be painful for the patient”.
Xing’s PhD will focus on merging x-ray imaging with CT scanning, so surgical teams have as much information as possible about the patient’s position standing up, sitting, and lying down.
Getting their start with the IHE Summer Studentship
That Xing is so clued up on the second day of her PhD is less surprising when you realise she’s worked with the team before.
Both Xing and Angelika got their first taste of this research through the IHE Summer Studentship, a programme providing UCL Engineering students with eight-week placements in clinical settings. Students gain first-hand experience working with clinicians and engineers on real healthcare engineering projects. They are both now PhD students in UCL Mechanical Engineering.
Angelika was part of our inaugural cohort in 2021, when she was an undergraduate student in medical physics. She was placed with Johann and Anna’s team.
“Medical physics is a combination of science and medicine. Getting a clinical or hospital-based internship is so difficult these days, so when I saw the IHE Summer Studentship, it really stood out to me – I was trying to gain that experience.”
“During the studentship, every day was different. Some days I went into the operating theatre to watch a surgery. There were other days when I was at the outpatient clinic, seeing the people who had previously been just a CT scan on a computer screen. Seeing them in real life made it so much more real. And sometimes I was working with PhD students and learning about their work”.
After completing her studies, Angelika reached out to Johann to see if he knew of any work opportunities. That’s when she was offered the PhD post.
Xing was also placed within the team when she completed the IHE Summer Studentship in 2023.
“I applied for the studentship because I knew I wanted to do a PhD, and I wanted to gain more research experience.”
“When I did my studentship, I was told, ‘Okay, this is what we’ve identified, this is the idea, now we need a way to actually execute it’. So, I think I had a lot of freedom to figure out how to get the outcome they wanted. I had the chance to see how surgeons interact with patients in the clinic and the impact it had on patients. That’s what made me interested in pursuing this, so I reached out to see if I could come back and join the team”.
Over the years, Anna and Johann have supervised seven summer students. They both believe the IHE Summer Studentship scheme has had enormous benefits for the team.
“The IHE Summer Studentship allows us to engage exceptional students in advancing our research and building larger projects with the potential to grow into PhD programmes, enriching both the students and our team”, says Anna.
Johann agrees, “The programme has really worked for us. Two out of seven going on to do a PhD is pretty impressive – I couldn’t have asked for more”.
“I think it works so well because they’ve had a taster, so they know exactly what they’re going into. They appreciate the challenges of working in a hospital, and the fact that they choose to do this over their summer holidays says a lot about them as individuals”.
It’s clear from my visit that the culture of this collaborative, productive environment starts from the top and enables the researchers to thrive. Johann and Anna’s summer students have gone on to publish their research in well-respected journals and present their work at conferences.
“This is about engineering meeting medicine”, says Johann. “I really want to sell the clinical side of what we do to engineers”.
Well, I’m already sold. The team at RNOH are an incredible example of what happens when we collaborate across disciplines and invest in the next generation of talent.
Acknowledgments:
Angelika and Xing’s placements were funded with generous support from the RNOH Charity.
More information:
- Main photo shows the team from left to right: Angelika Ramesh, Xing Lim, Sara de Angelis, Johann Henckel
- Anna di Laura’s research profile
- Johann Henckel’s research profile
- Angelika Ramesh’s research profile
- Sara de Angelis’ research profile
