With surgical-assisted technologies and services to track episode of care dominating joint reconstruction conversations in the AAOS 2017 Exhibit Hall, we stepped off the floor to ask Orhun Muratoglu, Ph.D., about research that could impact hip and knee devices in the coming decade.
Muratoglu, an ORTHOWORLD Member, has a long list of credentials:
- Director of the Harris Orthopaedic Laboratory and Director of the Technology Implementation Research Center (TIRC) at Massachusetts General Hospital
- Professor of Orthopaedic Surgery at Harvard Medical School
- Pioneer of highly cross-linked UHMWPE
- Pioneer of the use of antioxidant vitamin E to further stabilize highly cross-linked UHMWPE
When we sat down with Muratoglu, we wanted to understand the state of material use in joint reconstruction and his thoughts on the technology that will be implanted ten years from now.
Infections, pain management and dislocation are among hip and knee implant issues that need to be addressed, Muratoglu says. All of these concerns can be prevented with materials and load-bearing choices, which Muratoglu presented research on at AAOS.
Regarding infections, Muratoglu and his team are working on a two-stage revision in which polyethylene and gentamicin or vancomycin are mixed together and then machined into an implant, for instance a knee. Following implantation, the antibiotic would slowly release into the joint space, clearing the periprosthetic infection. Once the infection is cleared, a new device would be implanted.
Similar research is being done by mixing bupivacaine with polyethylene to control pain management. The bupivacaine would slowly release and be delivered to the joint over a period of time to provide pain relief and eliminate the need for opioids or other narcotics.
While Muratoglu wouldn’t say how far along the group’s research is, he predicts that in ten years such implants will be on the market. He expects that their technology to prevent hip dislocation will be ready much sooner, possibly by AAOS 2018.
“The way to decrease dislocation in the hip is to increase the head size,” Muratoglu says. “When you get to the really large heads, more hardware protrudes out of the acetabulum. What invariably happens is that some patients experience groin pain, because the implant sticks out and will impinge on the psoas muscle or other soft tissues.”
The answer to this problem, according to Muratoglu, is an anatomically contoured femoral component; think the shape of a mushroom. The femoral heads, known as Contoura, are under development by CeramTec.
The last focus of our conversation with Muratoglu was on the use of PEEK in hip and knee implants. He says that the fallout from metal-on-metal could continue to push researchers and companies to find alternatives to metal replacements. Invibio and Maxx Medical are already working on a PEEK-OPTIMA femoral knee.
Muratoglu’s early research showed that cross-linked polyethylene wear was lower with PEEK than with cobalt chrome. His prediction is that if PEEK doesn’t work, it will be because of fixation and not fatigue issues.
We asked whether ten years is too long to wait for these technologies. His response: “Ten years is nothing in orthopaedics.”