Potato, Potahto: Different Things Heighten Risk of Reoperation in Women and Men After TKA

by Elizabeth Hofheinz, M.P.H., M.Ed.

There’s no way around it…there are definitely modifiable risk factors when it comes to reoperation following total knee arthroplasty (TKA). A new study in the June 1, 2020 edition of The Journal of Arthroplasty, “Gender Differences in Contribution of Smoking, Low Physical Activity, and High BMI to Increased Risk of Early Reoperation After TKA,” has looked into ways to preoperatively identify individuals most at risk for reoperation.

Co-author Jiri Gallo, M.D., Ph.D. is with the Department of Orthopaedics at Palacky University Olomouc, Teaching Hospital in the Czech Republic. Dr. Gallo told OSN, “Our main motivation was to preoperatively identify patients at a high risk of undesirable outcomes associated with total knee arthroplasty (TKA) surgery, in particular: early reoperations (<2 years after primary surgery) after TKA, postoperative pain, and dissatisfaction. Despite the fact that the rate of these undesirable outcomes is relatively low, the number of patients who do not reach the expected outcomes of TKA worldwide is growing as the number of TKA surgeries is increasing. We believe we have to understand patients coming to the surgery much better as well as to continuously improve our clinical practice. This could result in a decrease of the percentage of revision operations as well as the level of dissatisfaction among the TKA patients.”

No way around high BMI…

“The analysis of the 25 preoperative parameters identified smoking, physical activity, and BMI as the main risk factors for early reoperation after TKA, with different contributions in men and women. For the group of females, low physical activity and high BMI were the most likely risk factors contributing to early reoperations. The risk of reoperation in the group of men was more likely associated with smoking or obesity (high BMI).”

“In our study we applied an innovative approach of multivariate network analysis bringing a great advantage over classical statistical approaches. The main advantage is its independence on the size of patient cohorts, the number of cases (in our study the number of reoperation), visualization of the relationships between patients based on multivariate analysis of any kind of data (clinical, laboratory, genetic), selection of the most relevant factors while reaching excellent interpretability.”

However, there is room for additional study…

“On the other hand, I have to admit that causal relations between the above variables and the reasons for early reoperation are difficult to explain. Therefore, further study will be required to demonstrate the clinical utility of the above-mentioned mathematical analysis.”

“Generally, our study illustrates the current potential of bioinformatic analysis, in this sense, our study is another piece of evidence. Identification of patient groups at a risk of early reoperation represents a crucial topic in the field of total arthroplasty surgery in the era of precision medicine (one would rather use the term ‘precision orthopaedics’).”

And it all comes back to how much motivation there is for the modifiable…and timing.

“The key message of our study is that physically active non-smoking men and women, particularly non-obese, have the lowest rate of early reoperations regardless of a particular reason for a revision surgery. However, a change in these modifiable risk factors is difficult or even impossible at the time just prior to TKA. These changes have to be realized much longer before a need for TKA perhaps except stop smoking which is of reasonable value always.”