Endoscopic Anterior Cruciate Ligament Reconstruction in Children Using Living Donor Hamstring Tendon Allografts

Background: The incidence of anterior cruciate ligament (ACL) injuries in children is increasing, but ACL reconstruction with traditional autograft sources is associated with high rates of further ACL injury when compared with adult populations. The outcome of ACL reconstruction using an alternative graft source, the living donor hamstring tendon (HT) allograft, has not been reported. Purpose: To determine the outcome of endoscopic transphyseal single-tunnel ACL reconstruction using living donor HT allografts. Study Design: Case series; Level of evidence, 4. Methods: Between 2007 and 2008, 32 children underwent endoscopic transphyseal single-tunnel ACL reconstruction using living donor HT allografts. The HT allograft was harvested from a parent. At a minimum 2 years' follow-up, full International Knee Documentation Committee (IKDC) knee ligament examination was performed on the children including instrumented testing using the KT-1000 arthrometer. Donors underwent subjective review at a minimum 2 years' follow-up. Results: Thirty-one children (97%) were able to be contacted for review. Of these, 2 (6%) sustained an ACL graft rupture within 2 years after surgery. Twenty-nine children completed clinical and subjective review. The mean age at ACL reconstruction was 13 years (range, 8-16 years). The mean HT graft size was 7.2 mm (range, 6-8 mm). The mean IKDC subjective score was 97 (range, 84-100). Twenty-eight patients (97%) had a normal or nearly normal IKDC ligament grade. At 2 years after surgery, 27 patients (93%) reported regularly participating in very strenuous or strenuous activities. There were no cases of limb malalignment. Twenty eight (97%) of the donors reported that they would undergo the same procedure again under the same circumstances. Conclusion: Excellent clinical and subjective outcomes were achieved with high levels of return to desired activities. This technique allows a more predictable size of the HTs compared with an autograft from the child and maintains an intact neuromuscular hamstring structure in the child. Finally, the child's own HTs are reserved for future use. Anterior cruciate ligament reconstruction using living donor allografts should be considered a viable choice in children.