Transphyseal anterior cruciate ligament reconstruction using living parental donor hamstring graft: excellent clinical results at 2 years in a cohort of 100 patients

Purpose: To determine outcomes of transphyseal ACL reconstruction using a living parental hamstring tendon allograft in a consecutive series of 100 children. Methods: One hundred consecutive juveniles undergoing ACL reconstruction with a living parental hamstring allograft were recruited prospectively and reviewed 2 years after ACL reconstruction with IKDC Knee Ligament Evaluation, and KT1000 instrumented laxity testing. Skeletally immature participants obtained annual radiographs until skeletal maturity, and long leg alignment radiographs at 2 years. Radiographic Posterior tibial slope was recorded. Results: Of 100 juveniles, the median age was 14 years (range 8–16) and 68% male. At surgery, 30 juveniles were graded Tanner 1 or 2, 21 were Tanner 3 and 49 were Tanner 4 or 5. There were no cases of iatrogenic physeal injury or leg length discrepancy on long leg radiographs at 2 years, despite a median increase in height of 8 cm. Twelve patients had an ACL graft rupture and 9 had a contralateral ACL injury. Of those without further ACL injury, 82% returned to competitive sports, IKDC ligament evaluation was normal in 52% and nearly normal in 48%. The median side to side difference on manual maximum testing with the KT1000 was 2 mm (range − 1 to 5). A radiographic PTS of 12° or more was observed in 49%. Conclusions: ACL reconstruction in the juvenile with living parental hamstring tendon allograft is a viable procedure associated with excellent clinical stability, patient-reported outcomes and return to sport over 2 years. Further ACL injury to the reconstructed and the contralateral knee remains a significant risk, with identical prevalence observed between the reconstructed and contralateral ACL between 12 and 24 months after surgery. Level of evidence: III (Cohort Study).