Aspirin may not be effective in prevention of deep vein thrombosis after meniscus root repair: a retrospective cohort study

Background: Arthroscopic knee surgery has been associated with a low risk of symptomatic deep vein thrombosis (DVT), with previous studies demonstrating a risk of 0.12% to 3.7%. This risk of DVT and ideal prophylaxis in cases of meniscus root repair are unknown. The authors sought to determine the effectiveness of aspirin as DVT prophylaxis after meniscus root repair. The hypothesis was that there is no significant difference in the risk of symptomatic DVT after meniscus root repair with aspirin prophylaxis as compared with low molecular weight heparin (LMWH) or apixiban. Methods: Patients treated with repair of medial or lateral meniscus root tears over a 3 yr period were identified retrospectively. The risk of subsequent development of a symptomatic DVT was compared based on whether postoperative DVT prophylaxis was undertaken with aspirin or a stronger anticoagulant such as LMWH or apixiban. Results: Fifty-eight patients who underwent root repair (19 lateral and 39 medial) were identified. No symptomatic DVTs were identified in 42 patients (0%) who received LMWH or apixiban, but DVTs were identified in 3 of 16 patients (19%) who received aspirin (P=0.018). No significant differences in patient gender or body mass index, laterality of repair, associated procedures, or smoking history were noted between the groups. The aspirin group included older patients (mean age 49 yr) than those in the LMWH/apixiban group (mean age 39 yr). Conclusions: Aspirin alone may not be sufficient to prevent DVT after meniscus root repair. Additional work is required to clarify ideal DVT prophylaxis following this procedure. Level of Evidence: Level III.