Pharmacologic Thromboprophylaxis Other Than Aspirin Is Associated With Increased Risk for Procedural Intervention for Arthrofibrosis After Anterior Cruciate Ligament Reconstruction

Purpose: To compare rates of procedural intervention for arthrofibrosis following anterior cruciate ligament reconstruction (ACLR) among patients who were not prescribed any pharmacologic thromboprophylaxis compared with patients who were prescribed aspirin and to patients who were prescribed other agents. Methods: A search of a national insurance claims database was performed to identify all patients who underwent ACLR from 2007 to 2017 who were active within the database at a minimum of 6 months before and 18 months after their surgery. The primary outcome studied was a subsequent procedure for arthrofibrosis, manipulation under anesthesia, and lysis of adhesions (MUA/LOA). Patients who filled a prescription for aspirin, low-molecular weight heparin, direct factor Xa inhibitors, fondaparinux, and warfarin within 2 days after their surgery were included and those who filled a prescription within 3 months before surgery were excluded. Thromboprophylaxis status was defined as no thromboprophylaxis, aspirin, and any agent other than aspirin. Logistic regression analysis was performed to determine the association between prophylaxis status and MUA/LOA. Results: Of the 14,081 patients in our final surgical population, 191 patients had MUA/LOA and 13,890 patients did not. In total, 499 patients were prescribed pharmacologic prophylaxis. Rates of MUA/LOA across groups were 1.3% in the group with no thromboprophylaxis, 1.9% in the group prescribed aspirin, and 4.3% in the group prescribed any agent other than aspirin. Only the group prescribed an agent other than aspirin was significantly associated with subsequent procedure for arthrofibrosis (odds ratio 2.6, 95% confidence interval 1.3-4.8, P = .004). Conclusions: Patients who were prescribed a pharmacologic agent other than aspirin had a 2.6