JOA - 2026-03-16 - Journal Article
Increased Risk of Postoperative Complications Following Total Knee Arthroplasty in Patients Who Have Metabolic Syndrome.
Smitterberg CW, Misch M, Katanbaf RM, Nace J, Mont MA, Delanois RE
Topics
Key Takeaway
Metabolic syndrome independently increases the 2-year odds of periprosthetic fracture by 2.84-fold and all-cause revision by 2.25-fold following TKA in a cohort of 1,255,079 patients.
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Summary
This study used a national all-payer database (2010–2023) to determine whether metabolic syndrome independently predicts mechanical, infectious, and revision complications after TKA using multivariable logistic regression. At 2 years, MetS was associated with significantly elevated odds of mechanical loosening (OR 1.62), periprosthetic fracture (OR 2.84), SSI (OR 1.79), PJI (OR 1.53), all-cause revision (OR 2.25), and septic revision (OR 1.85), with hypertension and diabetes identified as the strongest individual component predictors.
Key Limitation
Administrative coding cannot capture implant design, surgical technique, alignment philosophy, or degree of individual MetS component severity, all of which confound the complication risk estimates.
Original Abstract
BACKGROUND
Postoperative outcomes after total knee arthroplasty (TKA) are influenced by patient comorbidities. Metabolic syndrome (MetS) combines hypertension, diabetes, obesity, and dyslipidemia, which have been associated with increased short-term surgical complications. However, its independent impact on TKA outcomes beyond the perioperative period (> 90 days) remains unclear. This study compared outcomes following TKA between patients who had and did not have MetS, including (1) mechanical complications (mechanical loosening and periprosthetic fracture), (2) infectious complications (surgical site infection and periprosthetic joint infection), and (3) reoperations (all-cause revision, septic revision, and manipulation under anesthesia), at 90 days, 1 year, and 2 years.
METHODS
A national all-payer database was reviewed using International Classification of Diseases, Ninth and Tenth Revision codes to identify 1,255,079 patients who underwent TKA from 2010 to 2023. Among these, 386,813 (30.8%) had MetS. Outcomes were assessed at 90 days, 1 year, and 2 years. Student's t-tests and Pearson's Chi-square tests were used for unadjusted comparisons, and multivariable logistic regressions estimated odds ratios (ORs) with 95% confidence intervals (CIs).
RESULTS
At 2 years, MetS was associated with increased odds of mechanical loosening (OR 1.62, 95% CI 1.43 to 1.83, P < 0.001), periprosthetic fracture (OR 2.84, 95% CI 2.42 to 3.32, P < 0.001), surgical site infection (OR 1.79, 95% CI 1.70 to 1.87, P < 0.001), periprosthetic joint infection (OR 1.53, 95% CI 1.43 to 1.65, P < 0.001), all-cause revision (OR 2.25, 95% CI 2.06 to 2.46, P < 0.001), and septic revision (OR 1.85, 95% CI 1.04 to 3.34, P = 0.040). Among MetS components, hypertension and diabetes were the strongest predictors.
CONCLUSIONS
Metabolic syndrome is independently associated with increased risk of mechanical-, infectious-, and revision-related complications following TKA. These findings may help guide perioperative risk stratification, closer medical care coordination, and shared decision-making in this population.