Tobacco Use Is Associated with More Severe Adverse Outcomes Than Morbid Obesity after Aseptic Revision TKA

Impact of Obesity on the Outcomes of Aseptic Revision Total Knee Arthroplasty

BACKGROUND

Obesity is a known risk factor for complications following primary total knee arthroplasty (TKA), yet its impact on the outcomes of aseptic revision TKA remains less defined. This study evaluates the influence of body mass index (BMI) on revision, reoperation, and infection outcomes following aseptic revision TKA.

METHODS

A retrospective cohort of 2,836 first-time aseptic revision TKAs performed at a single academic institution from 2000 to 2022 was analyzed. Patient demographics, including BMI, were collected. The mean age was 69 years, the mean BMI was 33, and 42% were men. The main causes for the initial revisions were aseptic loosening (37%), instability (29%), and wear or osteolysis (13%). Kaplan-Meier survivorship, univariate Cox regression analyses, and multivariate Cox regression analyses adjusted for age, sex, indication for revision, and Charlson comorbidity index were used to assess the impact of BMI on the risks of revision, reoperation, and infection. The mean follow-up was seven years (range, 2 to 22 years).

RESULTS

The 5-year survivorships free from revision for periprosthetic joint infection (PJI), reoperation for PJI, any revision, and any reoperation were 96, 96, 89, and 85%. Univariate analyses showed that a BMI > 40 correlated with a trend towards increased reoperation for PJI (HR [hazard ratio] 1.4, P = 0.05) and a higher risk of reoperation for any reason (HR 1.3, P = 0.04). However, these findings did not remain significant when controlling for confounding factors with multivariate analysis.

CONCLUSION

Although a body mass index greater than 40 did impact the risk of subsequent reoperation following revision TKA on univariate analysis, these findings did not persist when accounting for confounding factors. These results suggest that the indication for revision plays a much larger role in outcomes following revision TKA for aseptic indications than BMI alone.

LEVEL OF EVIDENCE

IV (retrospective study).

Effects of smokeless tobacco use on primary total shoulder arthroplasty outcomes

BACKGROUND

Total shoulder arthroplasty (TSA) is a common procedure performed to treat a variety of shoulder pathology. Smokeless tobacco use in the United States has increased in recent years and prior studies have found smokeless tobacco use to be associated with increased rates of medical and surgical complications following lower extremity total joint arthroplasty. The purpose of this study is to evaluate the effects of perioperative smokeless tobacco use on the short-term postoperative outcomes following primary TSA.

METHODS

The Nationwide Readmissions Database was queried to identify patients who underwent primary TSA between 2016 and 2020. This cohort was further stratified into 3 cohorts: tobacco smokers, smokeless tobacco users, and nontobacco users. Subjects in both tobacco cohorts were matched at a 1:3 ratio with nontobacco users based on age, sex, and the presence of specific comorbid conditions. Demographics, postoperative complications, readmissions, revision, and mortality rates within 180 days of TSA were compared between the 3 groups.

RESULTS

Patients who use smokeless tobacco present with a greater mean Charlson-Deyo Comorbidity Index (5.1% vs. 1.8%) and concomitant alcohol use (5.1% vs. 1.8%). Smokeless tobacco users experienced significantly higher rates of Acute Respiratory Disease Syndrome (1.9% vs. 0.8%), sepsis (0.4% vs. 0.0%), and mortality (0.8% vs. 0.1) at 180 days.

CONCLUSION

Patients undergoing primary TSA who use smokeless tobacco are at an increased risk of mortality at 180 days and several medical postoperative complications including sepsis. Identifying these patients prior to their procedure and engaging in patient-centered discussion can help improve patient outcomes following primary TSA.

A mapping review on preoperative prognostic factors and outcome measures of revision total knee arthroplasty

To map literature on prognostic factors related to outcomes of revision total knee arthroplasty (rTKA), to identify extensively studied factors and to guide future research into what domains need further exploration. We performed a systematic literature search in MEDLINE, Embase, and Web of Science. The search string included multiple synonyms of the following keywords: "revision TKA", "outcome" and "prognostic factor". We searched for studies assessing the association between at least one prognostic factor and at least one outcome measure after rTKA surgery. Data on sample size, study design, prognostic factors, outcomes, and the direction of the association was extracted and included in an evidence map. After screening of 5,660 articles, we included 166 studies reporting prognostic factors for outcomes after rTKA, with a median sample size of 319 patients (30 to 303,867). Overall, 50% of the studies reported prospectively collected data, and 61% of the studies were performed in a single centre. In some studies, multiple associations were reported; 180 different prognostic factors were reported in these studies. The three most frequently studied prognostic factors were reason for revision (213 times), sex (125 times), and BMI (117 times). Studies focusing on functional scores and patient-reported outcome measures as prognostic factor for the outcome after surgery were limited (n = 42). The studies reported 154 different outcomes. The most commonly reported outcomes after rTKA were: re-revision (155 times), readmission (88 times), and reinfection (85 times). Only five studies included costs as outcome. Outcomes and prognostic factors that are routinely registered as part of clinical practice (e.g. BMI, sex, complications) or in (inter)national registries are studied frequently. Studies on prognostic factors, such as functional and sociodemographic status, and outcomes as healthcare costs, cognitive and mental function, and psychosocial impact are scarce, while they have been shown to be important for patients with osteoarthritis.

Morbidity and Mortality in Non-Obese Compared to Different Classes of Obesity in Patients Undergoing Transtibial Amputations

This study assesses the effect of obesity classes on outcomes and inpatient-hospital-cost compared to non-obese individuals undergoing below-knee amputations (BKAs). Retrospective matched-case controlled study performed on data from NIS Database. We identified three groups: N-Ob (BMI < 29.9 kg/m2; n = 3104), Ob-I/II (BMI: 30 to 39.9 kg/m2; n = 3107), and Ob-III (BMI > 40; n = 3092); matched for gender, comorbidities, tobacco use and elective vs. emergent surgery. Differences in morbidity, mortality, hospital length of stay (LOS), and total inpatient cost were analyzed. Blood loss anemia was more common in Ob-III compared to Ob-I/II patients (OR = 1.2; 95% CI = 1.1−1.4); blood transfusions were less commonly required in Ob-I/II (OR = 0.8; 95% CI = 0.7−0.9) comparatively; Ob-I/II encountered pneumonia less frequently (OR = 0.9; 95% CI = 0.4−0.9), whereas myocardial infarction was more frequent (OR = 7.0; 95% CI = 2.1−23.6) compared to N-Ob patients. Acute renal failure is more frequent in Ob-I/II (OR = 1.2; 95% CI = 1.0−1.3) and Ob-III (OR = 1.8; 95% CI = 1.6−1.9) compared to the N-Ob cohort. LOS was higher in N-Ob (13.1 ± 12.8 days) and Ob-III (13.5 ± 12.4 d) compared to Ob-I/II cohort (11.8 ± 10.1 d; p < 0.001). Mortality was 2.8%, 1.4%, and 2.9% (p < 0.001) for N-Ob, Ob-I/II, and Ob-III, respectively. Hospital charges were $22,025 higher in the Ob-III cohort. Ob-I/II is protective against peri-operative complications and death, whereas hospital cost is substantially higher in Ob-III patients undergoing BKAs.