To Resurface or Not to Resurface the Patella in Total Knee Arthroplasty, That Is the Question: A Meta-Analysis of Randomized Controlled Trials.

Background and Objetives: Currently, total knee arthroplasty is one of the most common surgeries, increasing with the increase in life expectancy. Whether or not to replace the patella has been a subject of debate over the years, remaining in controversy and without reaching a consensus. Over the years, different meta-analyses have been carried out in order to provide evidence on the subject, although, in recent times, there have not been many new studies in this regard. Therefore, it is considered necessary that the latest works form part of a new meta-analysis. Materials and Method: We searched the literature using PUBMED, SCOPUS, the Cochrane database and VHL from 2010 to 2020. The search terms used were "patellar" AND "resurfacing" OR "Replacement" and "no resurfacing" OR "no replacement". A meta-analysis was performed with Stata software (Stata version 15.1). Forest plots were generated to illustrate the overall effect of knee arthroplasty interventions. Results: As a result, it was obtained that there is a significantly higher risk of suffering AKP in the non-resurfacing group, in addition to a significant increase in the risk of undergoing a reoperation in the non-resurfacing group. On the other hand, significant differences were obtained in favor of the resurfacing group in both the clinical and Feller KSS, with functional KSS being inconclusive. After analyzing different variables throughout the literature, it does seem clear that the non-resurfacing group may present a higher risk of reoperation than the resurfacing group. Conclusions: For all these reasons, we think that, although it does seem that not replacing the patella can precipitate a reoperation, it is not clear whether this reoperation is a direct consequence of not having replaced the patella. Therefore, in our opinion, the treatment must be individualized for each patient.

Explanatory Factors for Periprosthetic Infection in Total Knee Arthroplasty.

There are many studies whose results reveal possible risk factors for developing an infection after a total knee arthroplasty (TKA). The objective of this study is to analyse the risk factors that depend on the hospital and, especially, if the patellar replacement influences the appearance of periprosthetic infection. A retrospective study was performed, where data from the electronic registry of patients of people over 18 and who had undergone TKA, between the years 2015 and 2018, were reviewed. Dependent variables on the patients and the health care system were collected. The possible associations between the factors and the appearance of infection after TKA were studied using univariate and multivariate regression analyses. A total of 907 primary knee arthroplasties were included in the study. Those patients who had their patella replaced had a significantly higher risk of developing an infection (OR 2.07; 95% confidence interval 1.01-6.31). Likewise, patients who underwent surgery by surgeons with more than 10 years of experience were more than twice as likely to become infected than those operated on by younger surgeons (OR 2.64; 95%CI 1.01-6.97). Male patients were also found to be three times more likely to be infected than women (OR 2.99; 95%CI 1.32-5.74). Those interventions that were longer had a higher risk of infection. The same happened with patients who stayed in the hospital for a longer period of time. The rest of the variables did not show statistically significant results. In this study, it was found that the replacement of the patella may be a factor of infection, but it should be corroborated with randomized clinical trials. Furthermore, patients who underwent longer surgeries or those with prolonged hospital stays should be closely monitored to detect infection as soon as possible and establish the most appropriate treatment.