Andrew Kowblansky

Background:  The incidence of anterior cruciate ligament (ACL) injuries in young athletes has increased, and, as of 2022, over 25% of all pediatric and adolescent knee injuries involved the ACL.¹ For complete ACL tears in skeletally immature patients, physeal-sparing ACL reconstruction (ACLR) is preferred, with average costs ranging from $13,000 to nearly $30,000.^2,4 Although return-to-sport rates after ACLR exceed 90% in this population, the risk of post-traumatic osteoarthritis (PTOA) remains a major concern.³ PTOA in young athletes can compromise knee function and diminish quality of life.

Methods:  A PubMed database search was conducted, including terms “skeletally immature”, “ACLR”, “lateral extra-articular tenodesis”, and “post-traumatic osteoarthritis”. Studies were selected based on their relevance to the topic and publication within the past 10 years.

Results:  Studies of isolated ACLR suggest that patients with greater postoperative knee laxity and instability are at higher risk for inferior long-term outcomes and may be more susceptible to developing PTOA.⁶ In a 10‑year prospective study of 146 young athletes who underwent isolated ACLR, the incidence of radiographic PTOA was 37% when defined by osteophytes and 23% when defined by joint space narrowing in knees whose contralateral limb showed no radiographic osteoarthritis.⁵ Although this cohort included a mixed age range, these findings support the concept that residual laxity and instability after ACLR may increase PTOA risk, potentially because altered knee mechanics increase abnormal articular cartilage loading. Biomechanical data from a cadaveric study indicate that combining ACLR with LET can reduce anterior tibial translation, internal rotation, and pivot‑shift displacement compared with ACLR alone, providing a mechanistic rationale that LET might mitigate PTOA risk by improving joint stability.⁷ However, more long‑term data on radiographic PTOA after physeal‑sparing ACLR with LET in skeletally immature patients is needed, and this theoretical benefit remains unproven in this population. In contrast, patient-reported outcomes (PROs) following ACLR with LET appear excellent in younger patients. In a long‑term cohort of skeletally immature athletes treated with physeal‑sparing over‑the‑top ACLR and LET, all Knee Injury and Osteoarthritis Outcome Score subscales remained above Patient Acceptable Symptom State thresholds at a mean 11‑year follow-up.⁸

Conclusions:  Physeal-sparing ACLR with LET in young patients appears to yield excellent long-term PROs, but its effect on PTOA incidence and severity remains uncertain. Future research should compare physeal-sparing ACLR with and without LET in young patients, with standardized imaging-based PTOA assessment to determine whether LET meaningfully reduces osteoarthritis risk.

Work Cited

1. Cancino, B., Muñoz, C., Tuca, M. J., Birrer, E. A. M., & Sepúlveda, M. F. (2022). Anterior Cruciate Ligament Rupture in Skeletally Immature Patients. Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews, 6(5), e21.00166. https://doi.org/10.5435/JAAOSGlobal-D-21-00166
2. Attri, M., D’Ambrosi, R., Farinelli, L., Malik, S. S., De Sa, D., Tapasvi, S., Fink, C., & Meena, A. (2025). ACL Reconstruction in Skeletally Immature Athletes: Current Concepts. Medicina (Kaunas, Lithuania), 61(4), 562. https://doi.org/10.3390/medicina61040562
3. Kay, J., Memon, M., Marx, R. G., Peterson, D., Simunovic, N., & Ayeni, O. R. (2018). Over 90 % of children and adolescents return to sport after anterior cruciate ligament reconstruction: a systematic review and meta-analysis. Knee surgery, Sports Traumatology, Arthroscopy, 26(4), 1019–1036. https://doi.org/10.1007/s00167-018-4830-9
4. Nicholas D Thomas, & Childs, B. (2023). The Cost of Pediatric ACL Reconstruction: A Narrative Review. Journal of Orthopaedic Business, 3(3), 14–16. https://doi.org/10.55576/job.v3i3.36
5. MOON Group, Everhart, J. S., Jones, M. H., Yalcin, S., Reinke, E. K., Huston, L. J., Andrish, J. T., Cox, C. L., Flanigan, D. C., Kaeding, C. C., Magnussen, R. A., Obuchowski, N., Parker, R. D., Pedroza, A. D., Sanders, R. A., Winalski, C. S., & Spindler, K. P. (2021). The Clinical Radiographic Incidence of Posttraumatic Osteoarthritis 10 Years After Anterior Cruciate Ligament Reconstruction: Data From the MOON Nested Cohort. The American journal of sports medicine, 49(5), 1251–1261. https://doi.org/10.1177/0363546521995182
6. Wang, L. J., Zeng, N., Yan, Z. P., Li, J. T., & Ni, G. X. (2020). Post-traumatic osteoarthritis following ACL injury. Arthritis research & therapy, 22(1), 57. https://doi.org/10.1186/s13075-020-02156-5
7. Van de Velde, S. K., Telfer, S., van Arkel, E. R. A., & Schmale, G. A. (2024). A lateral extra-articular tenodesis without additional hardware: Surgical technique and biomechanical comparison with an anatomic anterolateral ligament reconstruction in the augmentation of anterior cruciate ligament reconstruction. The Knee, 47, 112–120. https://doi.org/10.1016/j.knee.2024.02.003
8. Grassi, A., Dal Fabbro, G., Di Paolo, S., Aparo, F., Allhalalmeh, M. I., Lucidi, G. A., & Zaffagnini, S. (2025). High Long-term Survivorship From Revision After Physeal-Sparing “Over-the-Top” Anterior Cruciate Ligament Reconstruction and Lateral Tenodesis in Skeletally Immature Patients: 8- to 17-Year Follow-up. Orthopaedic journal of sports medicine, 13(12), 23259671251389126. https://doi.org/10.1177/23259671251389126