Matthew Dietz, M.D. is an Assistant Professor for the orthopaedics department at West Virginia University School of Medicine. In his surgical practice he performs primary hip and knee arthroplasties, including complex revisions—fueling his research focus on biophysical disruption of biofilms in total joint arthroplasty and the care of patients affected by prosthetic joint infection.
As is well-known, the Baby Boomer joint surgery candidate is a different kind of patient from her grandparents. She is a healthy patient with functional limitations, and as Dr. Dietz described, surgeons “want to provide efficient, safe, surgical care; we want to improve patient outcomes and limit complications. When we do have to deal with complications, we want to address them in a safe, effective manner.”
In the Knowledge Pod at OMTEC 2017, Dr. Dietz shared his take on challenges with patient care using present systems and devices, and offered thoughts on what he’d like to see in the future. Here are three points from Dr. Dietz’s Wish List:
We need to collect data that lets us know how we’re doing. However, with studies showing that 28% of our time is spent on patient care, while 43% of time is spent on data entry to feed electronic medical records, increasing numbers of surgeons are opting to leave the practice altogether. Data entry and data analysis need to be made easier. We need implants and technology that can help to collect information and report it to our healthcare providers.
Improved Debridement Strategies
When I perform debridement in an infected setting, I have to observe and decide what’s infected and what is not. It’s important that I have bone stock to build back into, and I also want to get rid of all of the infected material possible.
When doing a debridement, surgeons are encouraged to attend to the Four Cs: contraction, consistency, color and circulation. But I can’t tell you if bacteria is there and intracellular. I can’t tell if there’s biofilm adhering to that metal or bone or tissue.
If I do a full-scale debridement—if I treat this like cancer and take out all of the collateral structures—I can get a more thorough debridement, but I also end up with a much more mechanical knee, with greater limitations in the long run.
We can do better in providing a solution, an understanding of what defines an adequate debridement. What can we do to tell whether or not infection is present on that implant?
Advance Infection Detection
The diagnosis of infection is a problem. There is no gold standard that is 100% sensitive and specific to give us the answer: is that infected, or not? We’ve looked at aspiration of joint fluid, and if you observe the literature, numbers are all over the place as to what’s an optimal cut-off in number of white blood cells, with very different scenarios for the patient: six weeks out from surgery vs. three years out. Issues like this hinder our ability to define what infection is, though some very smart people (Drs. Parvizi and Gehrke) have helped to convene the Musculoskeletal Infection Society and craft major and minor criteria to get consensus on how we judge infection.
Newer technology is looking at biomarkers as a means to diagnose whether a certain joint is infected or not. There are limitations; this requires fluid aspiration, which is invasive—if you’ve never seen it done, patients hate it; it’s quite painful, there is significant variability depending upon the clinical situation and it’s still a send-out test. I have to take that fluid, send the patient home or admit him to the hospital, and I don’t get the results back until later that day or the next.
We’re looking for an implant or device that can tell us when it’s infected or compromised by biofilm. We want a test that is less- or non-invasive. We want it to be accurate and rapid—like a pregnancy test, we can know right away if it’s plus or minus, so we can come up with a plan to adequately treat our patients.
Dr. Dietz's full presentation, as well as slides from other surgeon speakers, can be accessed online.