2025 ISAKOS Congress in Munich, Germany

2025 ISAKOS Biennial Congress Paper


More ACL Graft Re-Injuries or Contralateral ACL Injuries During the First Season Back in Young Athletes Who Perceived Greater Return to Sport Bridge Program Improvement

John Nyland, EdD, DPT, Louisville, Kentucky UNITED STATES
Samuel Carter, MD, Louisville, KY UNITED STATES
Ryan Jeffrey Krupp, MD, Prospect, KY UNITED STATES
David N. M. Caborn, MD, Crestwood, KY UNITED STATES

Anchorage Public School, Anchorage, Kentucky, UNITED STATES

FDA Status Not Applicable

Summary

Subjects who sustained a new knee injury were younger, had greater perceived knee function at return to sport and most experienced the new injury during their first season back.

Abstract

Objective

Anterior cruciate ligament (ACL) graft failure or contralateral ACL injury after return to sport (RTS) post-ACL reconstruction and standard physical therapy remains problematic. This study evaluated the new injury outcomes of athletes who participated in a RTS bridge program.

Materials And Methods

Post-program objective functional tests, pre- and post-program Knee Outcome Survey Sports Activity Scale (KOS-SAS) scores, global knee function scores, sport knee function ratings, and sport performance ability perceptions were evaluated. Follow-up compared groups who either had or had not sustained a new knee injury (p ≤ 0.05).

Results

Two hundred and four athletes (19.7 ± 6 years of age, 108 males) completed the RTS bridge program and were released back to sports at 8.5 ± 2.4 months post-surgery. Groups had similar perceptions of returning to the same or better pre-morbid performance level (no new injury group = 84%, 157/187); and new knee injury group = 94%, 16/17, p = 0.27). Bilateral functional test symmetry results did not differ between groups. By 7.8 ± 4 years post-surgery, 17 subjects sustained either ACL graft re-injury (n = 6) or contralateral ACL injury (n = 11) with a similar frequency between males and females (p = 0.30). Six injuries (35%) occurred from contact to the surgical knee (n = 3, each during American football) or to the contralateral knee (n = 3, American football, wrestling, soccer). Eleven injuries (65%) involved non- or indirect contact to the surgical knee (n = 3, American football = 2, soccer = 1) or to the contralateral knee (n = 8, soccer = 3, basketball = 2, lacrosse = 2, taekwondo = 1). New knee injuries occurred during the initial RTS season (47%, n = 8), 1-year after RTS (n = 5, 29%), 2-years after RTS (n = 2, 12%), 5-years after RTS (6%, n = 1), and 10-years after RTS (6%, n = 1). Athletes that sustained another knee injury were younger at program initiation (17.1 ± 1.8 years vs. 20.9 ± 9 years, p = 0.04), more often had two-level sports knee function rating improvements (p = 0.01), more frequently scored ≥ the 25th percentile for KOS-SAS and global knee function scores (p ≤ 0.001), and had most new knee injuries during the initial RTS season (p = 0.01).

Conclusion

Although important, factors other than physical performance capability may possess a greater influence on athletes who sustain a new knee injury. Among some adolescent athletes re-injury may be related to strong athletic identity in combination with high confidence, low fear avoidance, poor risk appraisal and greater pressure from oneself, and perceived pressure from peers, coaches and parents/guardians.