Bias Does Not Exist in Treating Knee Periprosthetic Joint Infection Among Patients With Substance Use Disorder.

Debridement, antibiotics with implant retention (DAIR), and 2-stage revision are standard surgical interventions for treating knee periprosthetic joint infection (PJI). Patients with substance use disorder (SUD), especially addictive drug use disorder (DUD), have been shown to receive inferior medical care in many specialties compared with nonusers. The authors identified patients with a diagnosis of PJI after knee arthroplasty who received either DAIR or 2-stage revision with the Nationwide Inpatient Sample (NIS) database from 2010 to 2014. Patients were stratified into 2 groups, patients with DUD and nonusers, based on Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, criteria. Descriptive analysis was conducted to show the national trend for knee PJI treatment among the 2 patient groups. Multivariate logistic regression was used to compare the prevalence of DAIR and 2-stage revision between these 2 groups, adjusted for likely confounders, including age, sex, income, race, and comorbidities. Among the 11,331 patients with knee infection, 139 (1.23%) had DUD. Compared with nonusers, patients with DUD were significantly younger (P<.001), had more chronic conditions (P<.001), and were predominantly in lower income quartiles (P=.046). The 2 groups did not differ in sex and race (P=.072 and P=.091, respectively). The authors found that 30.22% of patients with DUD and 36.36% of nonusers received DAIR. The difference in these proportions was not statistically significant (P=.135). The results did not change after adjustment for confounding factors (P=.509). The findings suggested that bias does not exist among orthopedic surgeons who choose DAIR or 2-stage revision for knee PJI among patients with DUD. [Orthopedics. 2021;44(3):e385-e389.].

Lower Extremity Girth Does Not Predict Complications in TKA.

BACKGROUND: Obese patients have increased complications after total knee arthroplasty (TKA). A body mass index (BMI) cutoff of 40 is frequently used to determine eligibility for TKA. Patients with a BMI <40 and extremely large legs which may predispose them to complications are approved for surgery because they fall below this cutoff. Alternatively, patients with truncal obesity and a BMI >40 are accepted because they have thin legs. We sought to determine whether BMI or girth should be used to determine eligibility. METHODS: 453 patients who underwent TKA were included. A lower extremity girth (LEG) ratio was calculated dividing the width of the soft tissue envelope by bone width on lateral radiographs. Receiver operator curves were generated to predict 90-day complications. RESULTS: There was no difference in median LEG ratio between patients with or without a complication (P = .08). Receiver operator curves indicated that size of the soft tissue envelope had no utility in predicting complications. There was no correlation between LEG ratio and specific complications such as infection, malalignment, or wound complications. Using a LEG ratio threshold of 4.834, the sensitivity and specificity for predicting complications were 48% and 64%, respectively. The median BMI for patients with no complication was 32.3 and 35 for patients with a complication (P = .07). CONCLUSION: Complications are not necessarily associated with size of the soft tissue envelope in TKA.Decisions concerning TKA should not be made solely on the size of a patient's leg. LEVEL OF EVIDENCE: Level III (retrospective comparative study).

Ethnic Barriers to Utilization of Total Joint Arthroplasty Among Chinese Immigrants in the United States.

BACKGROUND: Previous studies have documented disparities in total joint arthroplasty (TJA) utilization among African American and Hispanic patients, but utilization among non-English-speaking Chinese patients in the United States has not been studied. METHODS: To quantify the utilization rate and detect ethnic factors effecting TJA utilization in non-English-speaking Chinese patients, data were gathered prospectively from the practice of a single fellowship-trained Caucasian surgeon from October 2012 to February 2013. A customized survey was drafted and validated in collaboration with a social scientist. Questions assessed demography, lifestyle factors, socioeconomic status, language skills, cultural beliefs, and prior experience with surgery. Surveys were administered in patients' native language and were collected in a blinded fashion. RESULTS: Overall, 269 patients were surveyed (157 Caucasian and 65 Chinese), 85 of which were recommended surgery (42 Caucasian and 26 Chinese). Seventy-six percent of Caucasian patients elected surgery, compared to 35% of Chinese patients. A multivariate logistic regression showed Chinese ethnicity to be a significant predictor of surgical decision after controlling for age, gender, socioeconomic status, and education. Several questions drafted to detect cultural differences in the aforementioned 6 categories were answered significantly differently (P < .05, chi-square). CONCLUSION: Language, lack of familiarity with surgery, lack of TJA knowledge, family members' role in decision making, and preference for a doctor of the same race may contribute to decreased utilization of TJA in this population. We believe a better understanding of the cultural beliefs and behaviors of Chinese patients will help physicians provide more optimal care to this patient population.

Twenty Percent of Patients May Remain Colonized With Methicillin-resistant Staphylococcus aureus Despite a Decolonization Protocol in Patients Undergoing Elective Total Joint Arthroplasty.

BACKGROUND: Staphylococcus aureus is the most commonly isolated organism in periprosthetic joint infection (PJI). Resistant strains such as methicillin-resistant S aureus (MRSA) are on the rise, and many programs have instituted decolonization protocols. There are limited data on the success of S aureus nasal decolonization programs and their impact on PJI. QUESTIONS/PURPOSES: The purposes of this study were to (1) determine the proportion of patients successfully decolonized using a 2-week protocol; (2) compare infection risks between our surveillance and decolonization protocol group against a historical control cohort to evaluate changes in proportions of S aureus infections; and (3) assess infection risk based on carrier type, comparing S aureus carriers with noncarrier controls. METHODS: We retrospectively evaluated a group of 3434 patients who underwent elective primary and revision hip and knee arthroplasty over a 2-year period; each patient in the treatment group underwent a surveillance protocol, and a therapeutic regimen of mupurocin and chlorhexidine was instituted when colonization criteria were met. A 2009 to 2010 comparative historical cohort was chosen as the control group. We compared risks of infection between our treatment group and the historical control cohort. Furthermore, in patients who developed surgical site infections (SSIs), we compared the proportions of each S aureus type between the two cohorts. Finally, we compared infection rates based on carrier status. Surveillance for infection was carried out by the hospital infection control coordinator using the Centers for Disease Control and Prevention (CDC) criteria. During the time period of this study, the CDC defined hospital-acquired infection related to a surgical procedure as any infection diagnosed within 1 year of the procedure. With the numbers available, we had 41% power to detect a difference of 0.3% in infection rate between the treatment and control groups. To achieve 80% power, a total of 72,033 patients would be needed. RESULTS: Despite the protocol, 22% (26 of 121) of patients remained colonized with MRSA. With the numbers available, there were no differences in infection risk between the protocoled group (27 of 3434 [0.8%]) and the historical control group (33 of 3080 [1.1%]; relative risk [RR], 0.74; 95% confidence interval [CI], 0.44-1.22; p = 0.28). In terms of infecting organism in those who developed SSI, S aureus risk decreased slightly (treatment: 13 of 3434 patients [0.38%]; control: 21 of 3080 patients [0.68%]; RR, 0.56; CI, 0.28-1.11; p = 0.11). Within the protocoled group, carriers had a slightly higher risk of developing SSI (carrier: seven of 644 [1.1%]; noncarrier: 18 of 2763 [0.65%]; RR, 1.77; CI, 0.74-4.24; p = 0.20). CONCLUSIONS: The screening and decolonization protocol enabled a substantial reduction in nasal carriage of MRSA, but some patients remained colonized. However, our nasal decolonization protocol before elective total joint arthroplasty did not demonstrate a decrease in the proportion of patients developing SSI. Future meta-analyses and systematic reviews will be needed to pool the results of studies like these to ascertain whether small improvements in infection risk are achieved by protocols like ours and to determine whether any such improvements warrant the costs and potential risks of surveillance and intervention. LEVEL OF EVIDENCE: Level III, therapeutic study.

The primary determinants of radiation use during fixation of proximal femur fractures.

OBJECTIVES: To establish the primary determinants of operative radiation use during fixation of proximal femur fractures. DESIGN: Retrospective cohort study. SETTING: Level I trauma centre. COHORT: 205 patients treated surgically for subtrochanteric and intertrochanteric femoral fractures. MAIN OUTCOME MEASURES: Fluoroscopy time, dose-area-product (DAP). RESULTS: Longer fluoroscopy time was correlated with higher body mass index (p=0.04), subtrochanteric fracture (p<0.001), attending surgeon (p=0.001), and implant type (p<0.001). Increased DAP was associated with higher body mass index (p<0.001), subtrochanteric fracture (p=0.002), attending surgeon (p=0.003), lateral body position (p<0.001), and implant type (p=0.05). CONCLUSION: The strongest determinants of radiation use during surgical fixation of intertrochanteric and subtrochanteric femur fractures were location of fracture, patient body position, patient body mass index, and the use of cephalomedullary devices. Surgeon style, presumably as it relates to teaching efforts, seems to strongly influence radiation use.