Crohn’s Disease is Associated With Implant-Related Complications Following Primary Total Knee Arthroplasty: A Matched-Control Analysis

Abstract

Introduction: Crohn’s Disease (CD) burdens a large percentage of Americans with rising prevalence in newly developed countries. Rates of primary total knee arthroplasty (TKA) have also increased in recent decades. While past studies have demonstrated a relationship between CD and outcomes and costs of TKA, there is still sparse evidence on specific postoperative complications. The purpose of this study is to reaffirm and further investigate the influence of CD on (1) in-hospital length of stay (LOS); (2) readmission rates; (3) implant-related complications; and (4) costs of care in patients undergoing primary TKA. Methods: A retrospective query using the Medicare claims database was performed from January 1st, 2005 to March 31st, 2014 for patients undergoing primary TKA with and without CD using ICD-9 diagnoses codes. CD patients receiving primary TKA were matched to non-CD patients in a 1:5 ratio by age, sex, and medical comorbidities, yielding 96,229 patients (CD=16,039; non-CD=80,190). Primary endpoints were in-hospital LOS, readmission rates, implant-related complications, and day of surgery and 90-day costs of care. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using logistic regression analyses. A p-value less than 0.05 was considered statistically significant. Results: Patients with CD undergoing primary TKA experienced significantly longer in-hospital LOS (3- vs. 2- days, p<0.0001) in comparison to non-CD patients. In addition, patients with CD suffered significantly higher readmission rates (19.8% vs. 14.9%; OR, 1.40; 95% CI, 1.34-1.47; p<0.0001) compared to non-CD patients. Total implant-related complications following primary TKA were also significantly higher in CD patients (6.88% vs. 4.88%; OR, 1.43; 95% CI, 1.34-1.54; p<0.0001). CD patients incurred significantly higher day of surgery ($18,365.98 vs. $16,192.00; p<0.0001) and 90-day costs ($21,337.46 vs. $19,101.42; p<0.0001) compared to their counterparts. Conclusion: This study demonstrated notably higher in-hospital LOS, readmission rates, implant-related complications, and costs of care in CD patients. Orthopedic surgeons may use this study to educate their higher-risk patients of potential postoperative complications.