Incidence and risk factor analysis of deep vein thrombosis following anterior cruciate ligament reconstruction: a retrospective cohort study

Deep vein thrombosis (DVT) is one of the severe complications following anterior cruciate ligament (ACL) reconstruction. This study aimed to investigate the incidence of DVT following ACL reconstruction in patients receiving mechanical thromboprophylaxis alone, and to identify high‑risk patient subgroups. This study enrolled 676 consecutive patients who underwent primary ACL reconstruction between 2018 and 2023. None of the patients received postoperative anticoagulation therapy. All patients received mechanical thromboprophylaxis, consisting of intermittent pneumatic compression and ankle pump exercises. Lower extremity duplex ultrasonography was performed on postoperative day 2 for DVT screening, with the incidence and anatomical location (proximal vs. distal segments) of thrombosis recorded accordingly. The collected data encompassed demographic characteristics, laboratory parameters, surgical variables, injury type, time since injury, and preoperative Caprini Score. Both univariate and multivariate regression analyses were performed to identify potential risk factors associated with DVT. Among the 676 patients, the mean age was 30.1 ± 8.8 years (range: 18–60), with 75% being male, and the average body mass index was 25.1 ± 3.9 kg/m 2 . The overall postoperative DVT incidence following ACL reconstruction was 6.4% (43/676), with proximal DVT at 0.4% (3/676) and distal DVT at 5.9% (40/676). Calf muscular vein thrombosis constituted 5.0% (34/676) of the entire cohort. Multivariate analysis, adjusted for potential confounders, identified age [odds ratio ( OR ) = 1.042, 95% confidence interval (CI) (1.004–1.083), P = 0.032] and preoperative C-reactive protein (CRP) positivity [ OR = 4.619, 95% CI (1.582–13.491), P = 0.005] as independent risk factors for postoperative DVT. The preoperative CRP-positive group exhibited a significantly higher incidence of postoperative DVT compared with both the CRP-negative group and the entire study population (28.2% vs. 5.0%, P < 0.001; 28.2% vs. 6.4%, P < 0.001). The overall incidence of early postoperative DVT following ACL reconstruction with mechanical prophylaxis alone was 6.4%, the majority of which were calf muscular vein thrombosis. Age and preoperative CRP positivity were associated with increased DVT risk; however, the clinical significance of these findings requires further validation in prospective studies.