How Do Venous Thromboembolism Rates in Adolescents and Adults Compare After Arthroscopic Knee Surgery? A Propensity-Matched Study.

Background: Arthroscopic knee procedures such as meniscus and ACL repairs are cornerstone interventions in pediatric and sports orthopaedics. While venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), is a rare yet devastating complication in major joint surgeries, its association with minimally invasive procedures remains relatively unexplored. Emerging evidence shows rates of VTE in adolescent orthopaedic patients approaching that of adults, highlighting the need to further characterize the unique risk profile of this population. Therefore, this study aims to compare VTE rates, risk factors, and chemoprophylaxis use in adolescents versus adults undergoing arthroscopic knee procedures.

Methods: A retrospective cohort study using the TriNetX Research Network identified 301,585 patients who underwent knee arthroscopy from January 2003 to January 2023, including 29,984 adolescents (aged 14 to 17) and 271,601 adults (aged 18 years or older). Propensity score matching based on sex and relevant comorbidities, including diabetes mellitus, tobacco use, oral contraceptive (OCP) use, and obesity yielded balanced cohorts of 29,984 each. Univariate logistic regression analysis was performed for preliminary assessment of the risk factors associated with VTE. P <0.01 was considered significant.

Results: Adults had a higher 90-day incidence of DVT (1.3% vs. 0.8%) and PE (0.3% vs. 0.2%) than adolescents. Combined DVT/PE incidence was 1.5% in adults and 0.8% in adolescents (RR: 1.782). Univariate analysis showed OCP use (OR: 3.167), obesity (OR: 3.445), tobacco use (OR: 23.975), and diabetes (OR: 34.064) were significant VTE risk factors in adolescents; sex was not. Adults more frequently received postoperative chemoprophylaxis (24% vs. 20%, P <0.001), with aspirin being the most common agent (23% in adults vs. 19% in adolescents, P <0.001).

Conclusion: Adolescents undergoing knee arthroscopy have a lower risk of VTE compared with adults, with an incidence below 1%. Routine VTE prophylaxis may not be necessary for all adolescents but should be considered for those with significant risk factors, including diabetes, tobacco use, and obesity. Further research is warranted to refine prophylaxis guidelines in this population.

Level of evidence: Level III-retrospective cohort study.