Management of ACL Injuries in the Skeletally Immature

Abstract and Introduction

Abstract

Background: Despite an increasing incidence of injury, there continues to be a paucity of literature, when compared with adult cohorts, for anterior cruciate ligament (ACL) disruption in skeletally immature patients. The detrimental long-term effects of chondral or meniscal damage resulting from an ACL deficient and unstable knee, has led most contemporary orthopaedic surgeons to opt for surgical intervention rather than nonoperative management. However, high failure rates in the young and adolescent group after formal ACL reconstruction, along with the potential risks of physeal disturbance, have been highlighted as a cause for concern. The aim of this review was to provide the state of art management of ACL injuries in skeletally immature patients based on the current evidence.

Methods: A literature review on the different management options of ACL injuries in skeletally immature patients was conducted. The authors searched PubMed entries from inception until April 2021. The search was performed with the search terms "ACL injuries" AND "skeletally immature".

Results: A comprehensive search related to the management of "ACL injuries" generated 13,157 results. Thus, search was narrowed to include the term "children" to focus our study on 570 papers. To further refine our search, we included the terms "ACL injuries" AND "skeletally immature," which produced 327 results.

Conclusion: This review highlights pros and cons of current treatment options, based on available evidence, including a detailed assessment of factors affecting the success of repairing the ACL. Overall, further Level 1 studies are necessary to improve the available evidence.

Level of Evidence: Level I.

Introduction

Anterior cruciate ligament (ACL) injuries in the pediatric age group are not uncommon.^[1,2] The burden of disease also continues to increase in this skeletally immature population, and currently estimated to be around 3.4% of all ACL injuries.^[2] A study examining insurance claims in soccer players aged 5 to 18 yr old found 22% of injuries to be knee related, of which a third involved an ACL injury.^[3] More recently, a study from Finland^[4] has demonstrated a rise in the incidence of pediatric and adolescent ACL injuries over an 18-year period, with a 143% increase in incidence in girls aged between 13 and 15 yr. This continued increase can be attributed to the improved availability of diagnostic imaging, as well as greater clinical awareness and understanding.^[5] Additionally, there has been a rise in the number of children and young athletes involved in high-demand sports.^[6] This rise has been recognized by Fédération Internationale de Football Association (FIFA) who have developed the FIFA 11+ program, which has shown a reduction in noncontact football injuries through a warm-up program.^[7]

"Children aren't little adults" is true especially when it comes to the patterns and management of ACL injuries. Previously, it was thought that disruption of the ACL integrity was associated with tibial spine avulsion in the skeletally immature patient. This, however, is a misconception which has been clearly highlighted by van der List et al.^[1] They demonstrated in a retrospective MRI study of 274 patients between the ages of 6 and 18 yr that ACL disruption occurs in different locations depending on the age of the patient. In the group between 6 and 10 yr old, there was a 93% prevalence of distal bony avulsions (tibial spine), compared with 2% in those between 14 and 17 yr old. Interestingly, the group aged between 11 and 13 yr had the equivalent of Sherman type 1 injury in 32% with Sherman type 2 in another 16% of patients (Figure 1).

(Enlarge Image)

Figure 1.

Sherman classification of anterior cruciate ligament (ACL) tears.

The treatment goals for all patients with an ACL injury, regardless of age, are a stable functional knee, prevention of further intraarticular damage, and expeditious return to daily activities and sport.^[8,9] There is relative paucity of literature about pediatric ACL ruptures when compared with adult cohorts.

Although the management of adults is transferable to patients with open physis, significant anatomical and physiological differences limit its application.^[2] Support does exist for both operative and nonoperative management for the skeletally immature patient with an ACL injury, with the majority of recently published literature leaning towards surgical intervention.^[9] The purpose of this study was to provide a comprehensive analysis and recommendations for management of pediatric ACL injuries based on the best available evidence.