Purpose: Total knee arthroplasty (TKA) is a frequently performed surgical procedure aimed at reducing pain, improving mobility, and restoring function in patients with advanced knee osteoarthritis. As patients undergoing TKA age, the prevalence of comorbidities, particularly diabetes, continues to rise. This study assesses post‐operative complications, healthcare costs and hospital length of stay (LOS) among diabetic patients undergoing primary and revision TKA using nationwide data from the NIS database, employing propensity score matching (PSM) to minimize confounding variables. We hypothesized that diabetic patients undergoing TKA would experience higher complication rates, greater healthcare costs and longer hospital stays compared to non‐diabetic controls.Methods: This retrospective cohort analysis utilized data from the Nationwide Inpatient Sample from 2016 to 2019, including a total of 2,602,484 TKA patients: 561,340 with type 2 diabetes and 2,041,144 without diabetes. PSM was applied to create balanced cohorts, adjusting for baseline demographic and clinical differences. Outcomes analyzed included LOS, total hospitalization charges, post‐operative complications and revision surgery rates. Statistical significance was set at p < 0.05.Results: Following PSM, diabetic patients exhibited significantly higher risks for post‐operative complications, including sepsis, heart failure and surgical site infections, compared to matched non‐diabetic controls. Diabetic patients also incurred significantly greater hospital charges ($64,694 vs. $59,952, p < 0.001). In revision TKA cases, diabetic patients demonstrated slightly longer LOS (3.5 days vs. 3.0 days, p < 0.001) and higher total hospital charges ($101,457 vs. $96,614, p = 0.015).Conclusions: Diabetic patients undergoing TKA experience significantly higher complication rates, hospital charges and revision surgery burden. Orthopaedic surgeons and perioperative teams should implement personalized perioperative management strategies, including optimized glycaemic control, cardiovascular risk assessment and infection prevention measures, to mitigate these risks and improve clinical outcomes.Levels of Evidence: Level III.

Background: Total knee arthroplasty (TKA) is one of the most frequently performed procedures for end-stage arthritis. Effective pain control is essential for recovery, and opioids are widely used. However, patients with opioid use disorder (OUD) may be at increased risk of complications. Methods: We analyzed 2,514,099 TKA cases from the Nationwide Inpatient Sample (2016–2019), identifying 11,785 patients with OUD. After 1:1 propensity score matching, clinical and economic outcomes were compared between OUD and non-OUD patients. Results: Patients with OUD had significantly higher odds of intraoperative fracture (OR: 6.1), DVT (OR: 5.0), pneumonia (OR: 2.5), pulmonary edema (OR: 1.6), and blood transfusion (OR: 1.5) (p < 0.001). Mean hospital charges were higher (USD 68,687 vs. USD 60,984), and LOS was longer (2.8 vs. 2.5 days, p < 0.001). OUD patients were more likely to undergo revision TKA at a younger age (59.6 vs. 65.4 years, p = 0.016), with higher infection rates and greater costs. Conclusions: Patients with OUD undergoing TKA experience more complications, higher costs, and require earlier revision. Underreporting of OUD highlights the need for improved preoperative screening.

Background: THA is a gold-standard intervention for end-stage hip osteoarthritis, historically performed in older adults. However, the growing global obesity epidemic is reshaping this landscape. Emerging evidence suggests that elevated body mass index (BMI) may not only worsen perioperative outcomes but also accelerate the need for surgery at a younger age. Understanding how BMI influences both the timing and safety of THA is crucial to optimizing care in this evolving patient population. Methods: We conducted a retrospective analysis of 1,626,965 elective THA hospitalizations from the Nationwide Inpatient Sample. Patients were stratified by BMI into three categories: <29.9, 30–34.9, and ≥35. Fracture- and oncology-related cases were excluded. ICD-10 codes identified comorbidities and complications. Primary outcomes included age at surgery, in-hospital mortality, length of stay (LOS), complications, and hospitalization costs. Statistical analysis used Pearson correlation, linear regression, chi-square tests, and t-tests via SPSS version 26.0.0.0. Results: Higher BMI was significantly associated with younger age at THA (r = −0.187, p < 0.001). Each 5-unit BMI increase corresponded to a ~2-year decrease in age at surgery. Obese patients had higher rates of hypertension, diabetes, dyslipidemia, and sleep apnea. Complications including blood loss anemia, acute kidney injury, venous thromboembolism, and postoperative infections were more common in higher BMI groups. LOS increased with BMI, though total hospital charges showed minimal clinical variation. Conclusions: Obesity is a key driver of earlier THA and elevated perioperative risk. These findings underscore the need for BMI-tailored surgical planning and risk stratification. As younger, high-BMI patients increasingly undergo THA, future strategies must focus on preoperative optimization, complication prevention, and long-term implant durability.