Treating Anterior Cruciate Ligament Tears in Skeletally Immature Patients.
Vavken P, Murray MM. Arthroscopy. 2011 May 1;27(5):704-716.
Anterior cruciate ligament (ACL) tears are common knee injury that are typically managed with ACL reconstructive surgery.  However, the typical transphyseal ACL reconstruction (passing through a growth plate) has been avoided among skeletally immature patients because of the risk of long-term physeal malfunction and secondary angular deformity or growth disturbances. As a result the standard of care in skeletally immature patients with an ACL tear has relied on conservative management until the patient is skeletally mature enough to undergo a reconstruction. In recent years, physeal-sparing ACL reconstruction techniques have been introduced. While studies have reported clinical results on these procedures little is known about how these surgeries compare to alternative treatment approaches (transphyseal reconstruction or conservative management). Therefore, Vavken and Murray performed a systematic review to evaluate the current evidence for conservative and surgical treatment of ACL tears in skeletally immature patients. The authors identified 47 articles (total of 1,256 patients; average age was 13 years) with an average follow-up of 45 months (minimum 6-month follow-up) and reported that conservative treatment led to poor clinical outcomes (e.g., laxity, low functional scores) and high incidence of secondary injuries/defects (e.g., meniscal degeneration/injuries and cartilage defects). The authors suggest that surgical stabilization should be considered the preferred treatment among skeletally immature patients. Furthermore, the selected procedure (transphyseal reconstructions versus physeal-sparing reconstructions) may have a smaller clinical impact than deciding to choose surgery instead of conservative management. The authors propose that while transphyseal reconstructions (adhering to a few established rules) can be safely done in skeletally immature patients there are physeal-sparing procedures that lead to comparable results with possibly less risk to the growth plate.
The authors reference other recent systematic reviews by Kaeding et al and Frosch et al (click names for abstract). Kaeding et al also reported that physeal-sparing and transphyseal reconstructions can lead to good clinical outcomes with a low incidence of growth complications. Frosch et al had similar findings but also reported that physeal-sparing techniques may increase the risk of leg length differences or angular deformity compared to transphyseal procedures. Overall, this study highlights that conservative or delayed surgical treatment for skeletally immature patients may increase the risk of secondary injuries and should be reserved for special cases (e.g., patients with low activity demands, no other knee injuries, highly compliant patients). It will be important for us to continue to follow these patients to evaluate their knees 10 years, 20 years, or even further down the road. Based on the current literature it appears that at least 20% of patients with ACL tears will develop osteoarthritis (some estimates go well above 50%), regardless of whether or not the skeletally mature patient has an ACL reconstruction (see Øiestad BE et al 2009). We’ll need more data to know what the incidence of osteoarthritis will be like in the younger population that this systematic review focused on. The sports medicine community needs to further explore ways of improving the long-term health of these patients (e.g., injury prevention programs, interventions to prevent joint degeneration after trauma).
Written by: Jeffrey B Driban
Reviewed by:  Stephen Thomas