Pediatric ACL Reconstruction

Four main surgical categories exist, with the technique matched to the patient’s Tanner stage and estimated remaining growth:

Extraphyseal (Physeal-Sparing) ACLR — For Prepubertal Children (Tanner Stage 1–2)

This technique avoids drilling any bony tunnels through or close to the physis, providing the highest degree of growth plate protection. The most widely used approach uses the iliotibial band (ITB) as the graft, passed from the lateral femoral condyle in an “over-the-top” position into the knee and sutured to the tibial metaphysis — entirely bypassing the physeal zones.

A landmark 23-year follow-up study by Kocher et al. reported a graft rupture rate of only 6.6% and no cases of limb length discrepancy or angular deformity. Biomechanical motion analysis confirms that this technique restores symmetric and physiologically normal kinetic and kinematic function in the growing knee. Cadaveric studies demonstrate that ITB reconstruction provides superior rotational control compared to all-epiphyseal and transtibial techniques. This technique is the preferred approach at our practice for prepubertal patients with significant remaining skeletal growth.

All-Epiphyseal ACLR — For Children with Significant Remaining Growth

The all-epiphyseal technique allows anatomical ACL reconstruction without drilling tunnels across the physis, by confining both femoral and tibial bony tunnels entirely within the epiphysis — the end portion of the bone beyond the growth plate. This technique is most commonly performed arthroscopically using an “all-inside” approach.

This approach is valuable for younger patients where transphyseal tunnels would remove significant physis volume. It is technically demanding, with a steep learning curve. While growth disturbances have been reported with this technique (the proximity of tunnels to the physis can stimulate vascular changes), outcomes are generally equivalent to other techniques, and three-dimensional intraoperative imaging has improved tunnel placement precision, reducing physis proximity risks. Pre-operative assessment of physis size is essential to ensure adequate bone volume for tunnel placement.

Partial Transphyseal ACLR — For Peripubertal Patients (Tanner Stage 2–3)

Designed for patients who are entering puberty with approximately 5–7 years of growth remaining, this hybrid technique uses an extraphyseal or all-epiphyseal femoral tunnel combined with a small transphyseal tibial tunnel. Because the femur contributes a greater percentage of overall limb growth than the tibia, confining the femoral tunnel to the epiphysis or extra-articular position while permitting a narrow transphyseal tibial passage minimizes overall growth disturbance risk while enabling effective ligament tensioning.

Published series using this approach have reported no limb length discrepancies in multiple patient cohorts, with mean height increases of 17.5 cm documented post-operatively — confirming preserved longitudinal growth. However, studies using strict MRI follow-up have identified that 16.7% of patients may develop some degree of growth disturbance, underscoring the need for surveillance to skeletal maturity in all cases.

Transphyseal ACLR — For Adolescents Near Skeletal Maturity (Tanner Stage 3–4)

The transphyseal technique — the standard adult ACL reconstruction approach — is appropriate for adolescents who are approaching skeletal maturity and have minimal remaining growth. Tunnels are drilled through the physis on both the femoral and tibial sides, using the same anatomic landmarks as adult reconstruction. This technique is familiar, reproducible, and does not require specialized intraoperative imaging.

Multiple published series demonstrate excellent outcomes: graft rupture rates of 3–11%, with no limb length discrepancies or angular malalignment in most cohorts when performed in appropriately selected (late Tanner stage) patients. A systematic review comparing physeal-sparing versus transphyseal techniques found equivalent Lysholm and Tegner activity scores between approaches, with statistically worse outcomes only in the non-surgical group. All patients undergoing transphyseal ACLR are followed to skeletal maturity to document and, if needed, address any growth disturbance.

Children have among the highest rates of ACL graft re-rupture of any age group. Anterolateral extra-articular procedures (AEAPs) — including lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR) — are increasingly performed alongside primary ACLR to reduce rotational instability and graft failure rates.

The current evidence supports adding an AEAP in pediatric patients with two or more of the following risk factors: generalized ligamentous hyperlaxity, more than 10 degrees of knee hyperextension (recurvatum), evidence of high-grade pivoting injury at the time of ACL tear (concurrent meniscus tear, lateral compartment osteochondral injury, or multi-ligament injury), and participation in pivoting, collision, or contact sports. Dr. Patel evaluates each patient for these risk factors when planning the surgical approach.