Effect of Patient Age on Morphology of Anterior Cruciate Ligament Grafts at Second-Look Arthroscopy

Purpose: The purpose of this study was to evaluate the effect of patient age on the morphology of anterior cruciate ligament (ACL) graft after ACL reconstruction, as well as to investigate the relation between morphology and clinical outcomes. Methods: Anatomic double-bundle ACL reconstruction by use of autogenous semitendinosus tendon graft was performed in 193 patients. Of these, 102 patients (51 male and 51 female patients) had consented to undergo second-look arthroscopy at the time of hardware removal within 2 years of ACL reconstruction. These patients were divided into the following 3 groups according to their age: group A, 29 years or younger (55 cases); group B, 30 to 49 years (36 cases); and group C, 50 years or older (11 cases). At second-look arthroscopy, the grafts were evaluated based on synovial coverage around the grafts, tension, and damage/tear of the grafts themselves. Clinical outcomes were evaluated with a physical examination including the Lachman test and side-to-side difference by KT-2000 knee arthrometer (MEDmetric, San Diego, CA), subjective assessment including International Knee Documentation Committee subjective assessment and Lysholm score, and sports activity level including Tegner activity scale. The Mann-Whitney U test, Kruskal-Wallis test, analysis of variance, and chi(2) test were used for statistical analysis. Results: Good synovial coverage over the graft was found in 49 cases (89%) in group A, 30 (83%) in group B, and 5 (46%) in group C. Synovial coverage in group C was significantly poorer than that in the other 2 groups. No statistical difference was found in tension of graft among the 3 groups, whereas the incidence of a "partial tear" tended to increase with age. With respect to clinical outcome, there was no significant difference among the 3 groups except for sports activity. Conclusions: Although clinical outcomes were comparable among the 3 groups, synovial coverage of ACL grafts in elderly patients was significantly poorer than that in younger patients. Level of Evidence: Level II, prognostic study.