Anterior Cruciate Ligament (ACL) injuries, once thought rare among pediatric and adolescent populations, have seen a notable increase in the last two decades1. This rise has been attributed to multiple factors, including the advent of high-demand, year-round sports at younger ages, improved clinician awareness, and better recognition of the signs and symptoms of ACL injuries2. When ACL tears occur in skeletally immature patients, the priority is to stabilize the knee; however, the optimal technique has not been completely agreed upon.

The physes of the knee provide a significant majority of lower extremity growth, with the distal femoral physis contributing 70% of femoral growth and the proximal tibial physis contributing 60% of tibial growth annually3. Historically, the potential for growth disturbances associated with traditional ACL tunnels led to a preference for non-operative treatments or delayed reconstruction until skeletal maturity4. However, studies have shown poor outcomes from non-operative management of complete ACL tears in skeletally immature patients, including progressive meniscus and cartilage damage, instability symptoms, and decreased activity levels5. A 2016 meta-analysis reported that patients treated non-operatively had a 12-fold greater risk of developing meniscal tears and were 33.7 times more likely to report instability compared to those undergoing early operative treatment6. Furthermore, delaying ACL reconstruction for more than 12 weeks significantly increases the risk of meniscal injuries and irreparable meniscal tears, with secondary tears observed in 17% to 44% of non-operatively treated patients7. The potential complications of traditional ACL reconstructions, along with the past tendency to delay surgery, have led to the development of new “physeal-sparing” and “physeal-respecting” surgical techniques designed to protect the growth potential of the physes.

Choosing the optimal ACL reconstruction technique depends on several factors, but most importantly, the skeletal age of the patient. It is our recommendation that physiologically younger patients with substantial growth remaining should undergo physeal-sparing techniques to mitigate the risk of significant growth disturbances3.

Iatrogenic physeal bar formation, leg length inequality, and angular deformity, although rare, are a concern with any skeletally immature ligamentous reconstruction. The all-epiphyseal Anderson technique and the Micheli-Kocher physeal sparing technique with iliotibial band have been the leading procedures in skeletally immature ACL reconstruction9,10. McCarthy et al. studied the risks of the all-epiphyseal technique and found that there is frequently an injury to the perichondral ring on the anteromedial tibia, concerning for developing an angular deformity with continued growth11. Other authors have demonstrated low risk of growth disturbance with transphyseal soft-tissue grafts, but these more vertical tunnels may result in a non-anatomic reconstruction12. Transphyseal suture fixation of tibial spine fractures has similarly shown minimal risk for physeal bar formation, even using two 3 mm diameter tunnels13.

Building on these previous efforts and with the goal of creating a biomechanically-stable, anatomic ACL graft that respects further growth potential., the senior author developed this novel technique. The technique combines a centrally-placed epiphyseal socket with transphyseal suture fixation on the tibia and an all-epiphyseal graft tunnel on the femur14 using a quadriceps tenon-bone autograft. This technique is described below and shown in Figure 1.