Background

Few studies have investigated the incidence, types and risk factors for reoperation after primary anterior cruciate ligament reconstruction (ACLR).

Purpose

To analyse the incidence, types and risk factors for reoperation within 2 years of primary ACLR.

Methods

Our clinic registry was used to identify primary ACLRs, performed from 2005 to 2015, and reoperations performed on the ipsilateral knee within 2 years at our institution. Reoperations were identified using procedural codes and analysis of medical records. A logistic regression analysis was used to evaluate risk factors for reoperation.

Results

A total of 6,030 primary ACLRs were included. A total of 1,112 (18.4%) reoperations performed on 1,018 (16.9%) primary ACLRs were identified. The most common reoperations were screw removal (n = 282, 4.7%), meniscus procedures (n = 238, 3.9%), cyclops removal/notchplasty (n = 222, 3.7%) and reoperations due to graft rupture (n = 146, 2.4%), including revision ACLR. Age < 30 years (OR 1.57; 95% CI 1.37-1.80; P <0.001), female gender (OR 1.33; 95% CI 1.17-1.51; P <0.001), medial meniscus repair (OR, 1.55; 95% CI 1.23-1.97; P <0.001), lateral meniscus resection (OR 1.26; 95% CI 1.07-1.49; P = 0.005) and lateral meniscus repair (OR 1.38; 95% CI 1.03-1.85; P = 0.02) at primary ACLR were found to be risk factors for reoperation.

Conclusion

One sixth of all primary ACLRs underwent reoperation due to complications or new injuries within 2 years. The most common reoperations were screw removal, meniscus procedures, cyclops removal/notchplasty and reoperations due to graft rupture, including revision ACLR. Younger age (< 30 years), female gender, medial meniscus repair and lateral meniscus resection or repair at primary ACLR were associated with an increased risk of reoperation. This study provides clinicians with important data to inform patients about the short-term reoperation rates, the most common reoperation procedures and risk factors for reoperation after primary ACLR.