Management of Paediatric Anterior Cruciate Ligament Injuries

Original Editor - Trista Chan

Top Contributors - Trista Chan, Kim Jackson and Vidya Acharya  

Introduction

ACL (anterior cruciate ligament) injuries are increasingly prevalent among children and adolescents, impacting their sports participation and overall quality of life. Choosing the right management strategy—surgical reconstruction or nonoperative treatment—can be complex and must consider the patient's age, skeletal maturity, and activity level. Recent research provides valuable insights into the best practices for managing ACL injuries in this age group.

Management Strategies for Pediatric ACL Injuries

Historically, nonoperative treatment, including activity modification and bracing, was preferred to avoid potential damage to the growth plates. However, recent studies suggest a shift towards early surgical intervention for better outcomes.

Operative vs Conservative Management

Research on children's anterior cruciate ligament (ACL) injury management is notably limited. While there is a substantial body of evidence addressing ACL injuries in adults, studies focusing specifically on skeletally immature patients are scarce. This gap is significant given the unique considerations for treating ACL injuries in children, such as growth disturbances and the high risk of recurrent instability. The few available studies highlight the challenges and limitations of applying adult-based treatment protocols to younger populations, underscoring the need for more targeted research to guide effective management strategies for pediatric ACL injuries.

Evidence in Paediatric Population

In recent years, there has been a notable rise in anterior cruciate ligament (ACL) injuries among children and adolescents, leading to a significant increase in ACL reconstructions for patients under 15 years of age. This shift is attributed to increased youth sports participation and early specialisation . Historically, skeletally immature athletes with ACL tears were managed conservatively due to concerns about physeal damage, but evidence now supports earlier reconstruction to prevent secondary chondral and meniscal damage. Current practices emphasise the importance of assessing skeletal maturity and choosing appropriate surgical techniques based on the remaining growth, such as physeal-sparing or transphyseal reconstruction. Despite these advancements, most research and evidence predominantly focus on adult populations, leaving a critical gap in tailored treatment protocols and outcomes for younger patients.

Bixby and Heyworth (2024) discuss how ACL tears in children and teens are managed, noting the significant effects on their lives, including sports and academics. ACL injuries are common, especially in young female athletes. Traditionally, nonoperative treatments like rehab and bracing were used to avoid harming growing bones. However, Surgery is increasingly preferred for better knee stability and fewer future injuries. Surgical options vary by age: children who haven't started puberty get one type of Surgery, while those who have or are close to adulthood get different techniques. Surgery is generally favoured because it leads to better outcomes and fewer complications, although growth issues are a concern and must be monitored after Surgery .

Pediatric ACL reconstruction presents unique challenges due to the risk of growth disturbances, including limb length discrepancies and angular deformities. Key mechanisms include physeal bridge formation and graft tension across the physis, which can lead to significant growth alterations. Techniques to minimise these disturbances emphasise reducing damage to the growth plate, careful graft selection, and precise surgical techniques. Despite the benefits of early reconstruction to prevent further damage in unstable injuries, the procedure carries risks, highlighting the need for standardised assessments and long-term follow-up and establishing national pediatric ligament registries for better data collection and outcome tracking.

Evidence in Adult Population

The systematic review by Papaleontiou et al. (2024) assessed surgical versus conservative management of ACL injuries through four studies involving 426 participants over 18 years old. The review found that surgical ACL reconstruction (ACLR) generally results in better knee function and stability than nonoperative treatment. Specifically, patients who underwent ACLR had a higher mean IKDC score (86.7) than those treated conservatively (77.5), and they showed significantly better knee stability, with 76% achieving normal stability compared to 33% in the conservative group. However, it took longer for patients who had Surgery to return to sports (24 weeks) than those who managed without Surgery (15 weeks). Additionally, ACLR resulted in less knee laxity, with a mean anterior tibial translation of 1.5 mm versus 4.5 mm for the conservative group . While ACL reconstruction provides superior long-term outcomes regarding knee stability and function, conservative management remains a viable option for some patients. However, it may involve longer recovery and higher knee laxity.

Park et al. (2024) conducted a study to evaluate the ligamentous stability and functional outcomes of nonoperative treatment for acute ACL injuries, comparing early versus delayed initiation of therapy. The study included 106 patients with confirmed ACL injuries following a structured nonoperative rehabilitation program divided into six phases over at least 12 months. Key findings indicated that patients who began nonoperative treatment within two weeks of injury generally achieved better ligament stability and functional status. At one year, 80% of patients showed maintained or improved stability, significantly improving Lachman Test (LT) and Pivot Shift Test (PST) scores. Nonoperative treatment was particularly indicated for partial tears, young children, low-risk activities, isolated ACL injuries, and cases with mild pathological laxity.

The Delaware-Oslo ACL Cohort Study by Grindem et al. (2018) provides valuable insights into the outcomes of non-surgical management for ACL injuries. Their research indicates that older female patients who demonstrate good knee function early after an ACL injury are likelier to report favourable symptoms and functional outcomes in sports two years later. Among active patients who opted for non-surgical management, 52-56% achieved successful outcomes within two years. However, approximately 33-37% eventually required delayed ACL reconstruction, while 11% of patients remained ACL deficient and reported poor knee function. Notably, only 5% of those who stayed ACL deficient at the two-year mark failed to achieve an acceptable symptom state. The study highlights the potential for successful outcomes with conservative management. However, it also notes limitations, such as discrepancies in methodologies like strength testing and hop tests, which may affect the generalisability of the results.

De Jonge et al. (2024) conducted a systematic review and meta-analysis comparing ACL reconstruction (ACLR) and nonoperative treatment for isolated ACL injuries in individuals aged 20-50. The review highlights that nonoperative treatment is associated with a 50% lower likelihood of developing knee osteoarthritis than ACLR, although this result lacks statistical significance due to variability in study designs. Both treatments show similar rates of return to play, though ACLR often provides better knee stability and allows for higher levels of sports participation. The review found no significant difference in subsequent surgical procedures or functional outcomes over 5-10 years. Given the current evidence, nonoperative treatment with a structured rehabilitation program is suggested as the primary approach. At the same time, ACLR may be considered for its potential to provide better stability and protect against further injuries. The authors call for future research with standardised protocols and reporting systems to clarify these findings.

Filbay (2022) provides an overview of recent evidence on managing anterior cruciate ligament (ACL) injuries, focusing on the ACL SNNAP trial conducted in the UK's National Health Service. This study compared ACL reconstruction with rehabilitation and optional delayed ACL reconstruction for patients with longstanding knee instability (up to 10 years post-injury) who had not previously undergone rehabilitation. Results showed that ACL reconstruction was favoured over rehabilitation and optional delayed reconstruction, with an adjusted mean difference of 7.9 (95% CI 2.5–13.2) in the Knee Injury and Osteoarthritis Outcome Score (KOOS) at 18 months. Comparisons with other trials like KANON and COMPARE also indicate some benefits of early ACL reconstruction, though differences in knee function were not always clinically significant. The quality and duration of rehabilitation varied between trials, with the SNAPP trial setting a minimum standard of six sessions over three months. Delayed ACL reconstruction timing and individual patient factors like self-efficacy and preoperative knee function are crucial in outcomes. The study suggests initial rehabilitation for acute ACL injuries and ACL reconstruction for longstanding knee instability without prior rehabilitation, highlighting the importance of individualised treatment plans and considering patient preferences and outcomes .

The Choice of Surgical Technique

The types of surgical techniques used often depend on the skeletal maturity of the patients. Using physeal-sparing or physeal-respecting surgical methods based on the patient's skeletal maturity and avoiding techniques that may interfere with average growth minimises damage to the growth plates.

These are some common techniques used:

• Physeal-Sparing Techniques: Recommended for prepubescent children to avoid damaging the growth plates.
• Physeal-Respecting Techniques: Suitable for adolescents who are close to skeletal maturity.
• Adult-Type Techniques: Used for patients whose growth plates are closed.
• Monitoring for growth disturbances post-surgery is essential, and techniques to minimise risks include careful graft selection and surgical precision.

Information on ACL management

Gamble et al. (2022) highlighted a gap in online information regarding ACL management. Many resources provide misleading information about treatment options and recovery, underscoring the need for accurate, evidence-based patient education. Most consumer webpages on ACL rupture management fail to align with the best available evidence and guidelines, presenting a skewed view of treatment options. Less than half of these sites suggest that returning to some form of sport is possible with non-surgical management, and only 20% mention activity modification as a viable treatment option. Furthermore, only 25% acknowledge the risk of re-injury when resuming sports post-ACL reconstruction, and a mere 4% highlight that approximately two-thirds of individuals return to their pre-injury sports levels. The benefits of ACL reconstruction (ACLR) are emphasised more frequently than non-surgical management, with webpages authored by surgeons often highlighting ACLR's advantages and potential to reduce osteoarthritis risk. This imbalance in information can lead to unrealistic expectations and may not fully support informed decision-making for patients and their families.

Clinical Implication

Choosing between ACL reconstruction (ACLR) and nonoperative treatment should be tailored to the patient's condition, preferences, and lifestyle. A balanced understanding of each option's potential risks and benefits is essential for making informed decisions. Setting realistic expectations is crucial, as outcomes can vary significantly based on individual factors such as activity level, injury severity, and overall health. While increasing evidence supports conservative management for ACL ruptures, the current literature is limited in its applicability to the pediatric Population, necessitating cautious and individualised clinical decision-making.