Review Question - QID 219968

The patient is a 12-year-old skeletally immature athlete with an ACL rupture, thus a physeal-sparing reconstruction technique that utilizes soft tissue autograft and minimizes tunnel size should be chosen.

ACL ruptures in skeletally immature athletes require special considerations given the proximity of the growth plates to the area of ligament reconstruction. Non-surgical treatment leads to ongoing activity-related symptoms and failure to return to healthy fitness and pre-injury level of sports activity, with subsequent unaddressed knee instability pre-disposing to additional meniscal and chondral injury, making conservative treatment a poor choice for adolescents with ACL injuries. Treatment options are many but have generally been delineated into using iliotibial band reconstruction (Answer 3) for pre-adolescent patients, either partial trans-physeal or all-epiphyseal forms of ACL reconstruction for patients approaching skeletal maturity (Answer 2), and trans-physeal autograft for skeletally mature adolescents (Answer 1).

DeFrancesco et al. review the challenges inherent in the management of ACL ruptures in skeletally immature patients. The authors note that although drilling 5% of the physis is associated with minimal risk of growth disturbance, the risk of growth disturbance generally increases with the proportion of the physis that is violated during surgery, with central physeal drilling being associated with a lower risk of growth arrest compared with peripheral drilling, and vertical tunnels minimizing physeal volume injured. They conclude that, although a variety of techniques are available for ACL reconstruction, orthopedic surgeons must select the technique appropriate for each patient based on the demands of their skeletal age, a process that can be guided by the algorithm they devise, which is reproduced in Illustration A.

Frank et al. review the diagnosis and management of ACL injuries in skeletally immature athletes. The authors note that the management of ACL injuries in skeletally immature patients includes physeal-sparing, partial trans-physeal, and complete trans-physeal ACL reconstruction. The partial trans-physeal technique involves a hybrid of physeal-sparing reconstruction and traditional trans-physeal procedures performed in adults, traditionally using either hamstring or bone-patellar tendon-bone grafts, with either the distal femoral or the proximal tibial physis left undisturbed, using smaller (6 to 8 mm) and more vertical bone tunnels to limit to <5% the overall cross-sectional area of physis that is interrupted. They conclude that In prepubescent patients (boys ≤12 years and girls ≤11 years), physeal-sparing combined intra- and extra-articular reconstruction using autogenous iliotibial band is recommended, while in adolescent patients with growth remaining (boys 13 to 16 and girls 12 to 14 years) all-epiphyseal or trans-physeal reconstruction using autogenous quadrupled hamstring tendons with smaller, more vertical tunnels and metaphyseal fixation are recommended compared to the more anatomic adult-type ACL reconstruction with autogenous quadrupled hamstring or bone-patellar tendon graft and interference screw or aperture fixation that is used in older adolescent patients with closing physes (males >16 years and females >14 years).

Figures A-C represent sequential T2-weighted sagittal MRI images from lateral to medial of a skeletally immature patient with open physes demonstrating the typical bone-bruising pattern associated with a non-contact ACL injury, with edema of the mid-portion of the lateral femoral condyle and the posterolateral aspect of the tibial plateau, as well as a complete rupture of the fibers of the ACL. Illustration A reproduces the treatment algorithm proposed by DeFrancesco et al. for the treatment of ACL ruptures in adolescent patients.

Incorrect Answers:
Answer 1: Patellar tendon autograft is not typically harvested in skeletally immature patients given the risk for physeal arrest; thus, soft tissue autograft is preferred in this setting.
Answer 3: IT Band ACL reconstruction is reserved for pre-adolescent patients, not a 12-year-old athlete with two years of growth remaining.
Answer 4: Though partial trans-physeal or hybrid reconstruction with hamstring autograft would be appropriate in this setting, the chosen bone tunnel should be <8mm in diameter to avoid drilling through more than 5% of the cross-sectional area of the physis.
Answer 5: Complete trans-physeal ACL reconstruction with the use of a bone block is appropriate for a patient with limited remaining growth or a skeletally mature athlete, but not for a 12-year-old, as mentioned above.