Pediatric and Adolescent ACL Reconstruction: Is Delaying Surgery Doing More Harm Than Good?

Commentary The timing of anterior cruciate ligament (ACL) reconstruction in pediatric and adolescent patients remains a complex topic with a myriad of factors to be considered. Historically, concerns about growth plate disturbances from ACL tunnels led to recommendations for activity modification and a delayed surgical procedure near or after physeal closure. However, a push to early reconstruction is becoming the contemporary norm due to advances in physeal-sparing ACL reconstruction techniques in combination with mounting scientific evidence indicating a risk of further injury to the ACL-deficient knee in young, active patients undergoing delayed operative management1-3. Although prior studies have used specific time cutoffs and odds ratios when evaluating the risk for further meniscal and chondral injury with delays to the surgical procedure in the ACL-deficient pediatric or adolescent knee1,2, Kolin et al. take a novel approach in evaluating the cumulative risk of a meniscal injury secondary to surgical delays in pediatric and adolescent patients undergoing ACL reconstruction. In this Level-IV retrospective cohort study, the time from the injury to the surgical procedure was categorized as a continuous variable rather than a discrete or categorical variable, and multivariable Poisson regression models were used instead of odds ratios in order to avoid an overestimation of risk. The authors found that, in a study population of 546 pediatric or adolescent patients, each week of delay in ACL reconstruction led to a 3% increase in risk of a medial meniscal injury in male patients. This led to an identified risk increase of >30% for each 10-week delay to ACL reconstruction in male patients and almost 80% in obese male patients (defined as those with a body mass index of >95th percentile for age). The authors also found that the use of crutches lowered the risk of both medial and lateral meniscal injuries during the interval between the ACL injury and reconstruction. Although Kolin et al. should be applauded for their novel approach to evaluating the risk for a meniscal injury with delays in ACL reconstruction in a pediatric and adolescent population, the use of the sole end point of a meniscal tear found at the time of the surgical procedure lacks clarity. The true risk of developing a meniscal tear in the interval between the injury and the surgical procedure would be best assessed by specifically identifying meniscal tears found at the surgical procedure that were not present on the magnetic resonance imaging (MRI) scan obtained following the injury. Although the article states that the MRI scan dates were obtained and were required for inclusion in the study, specific numbers delineating the number of medial or lateral meniscal tears found on the MRI scan compared with the surgical procedure are lacking, as are data about the number of new meniscal tears that developed between the MRI scan and the surgical procedure. It is well established that medial meniscal tears tend to develop over time in an ACL-deficient knee and that lateral meniscal tears are more prone to occur at the time of an ACL injury4,5, but it cannot be assumed that all medial meniscal tears found at the time of an ACL reconstruction developed while waiting for the surgical procedure rather than at the time of the injury. Such an assumption can lead to an overestimation of the risk of a meniscal injury related to delays in ACL reconstruction. This article could also have shed further valuable light on the risk of a chondral injury from a delay to ACL reconstruction. This topic would be an important area for future work to evaluate using the same methodology that Kolin et al. used to evaluate the risk for a meniscal tear in the present study. Nevertheless, this overall well-done study adds to the mounting evidence that delaying ACL reconstruction in pediatric and adolescent patients can lead to deleterious effects to the ACL-deficient knee. With advances in physeal-sparing ACL reconstruction techniques and a patient population that may find it hard to comply with activity modification while waiting for the surgical procedure, the authors’ findings of a 3% increased risk for a medial meniscal injury per week of surgical delay in pediatric and adolescent male patients awaiting ACL reconstruction should provide surgeons with food for thought when considering the timing of ACL reconstruction in the pediatric and adolescent population.