Evaluation of graft maturation by MRI in anterior cruciate ligament reconstruction with and without concomitant anterolateral ligament reconstruction

Abstract

<p><strong>Background</strong></p><p>It is shown in meta-analysis that single-bundle anterior cruciate ligament reconstruction (SBACLR) with concomitant anterolateral ligament reconstruction (ALLR) is associated with better clinical results when compared with isolated SBACLR. However, it is not known whether the improved clinical outcome is a result of the positive influence of the concomitant ALLR in the healing of the graft of ACLR.</p><p><br></p><p><strong>Hypothesis</strong></p><p>The objective of this study is to determine if concomitant ALLR is associated with signal-noise quotient (SNQ) of the ACLR graft. It is hypothesized that ALLR will not affect graft healing as measured by SNQ. </p><p><br></p><p><strong>Study Design</strong></p><p>Cohort study with one-to-one matching; Level of evidence, 3.</p><p><br></p><p><strong>Methods</strong></p><p>A one-to-one matching study was conducted on a consecutive series of 732 patients who underwent ACLR using hamstring autograft between 2007 and 2019. Patients were excluded if they had skeletal immaturity, inflammatory joint disease, multiple ligament reconstruction (other than ALLR), or a graft rupture. Patients with SBACLR-ALLR and isolated SBACLR were matched one-to-one based on age, sex, examination-under-anaesthesia (EUA) grade 3 pivot shift phenomenon, EUA grade 3 anterior drawer test, presence of graft impingement, sagittal graft angle, skeletal maturity, generalized ligamentous laxity, and multiple ligament injury. A total of 40 matched pairs underwent post-operation MRI within the second year after surgery to assess graft ligamentization by measuring the SNQ. Inter-observer and intra-observer repeatability checks were performed. </p><p><br></p><p><strong>Results</strong></p><p>The average follow-up period was 41 months, with a 2-year follow-up rate of 80% in the concomitant SBACLR-ALLR group and 98% in the isolated SBACLR group. SNQ was measured in 40 matched pairs. The mean duration between the index operation and MRI was 16.4 +/- 3.4 months. No significant difference was observed in the SNQ of the ACLR graft between the SBACLR-ALLR (6.9 +/- 4.6) and SBACLR (5.2 +/- 4.8) groups (p=0.066). </p><p><br></p><p><strong>Conclusion</strong></p><p>The addition of an ALL reconstruction at the time of hamstring autograft ACL reconstruction had no effect on SNQ of the ACL graft. The ALL reconstruction did not appear to affect graft healing as measured by SNQ. </p><p><br></p><p><strong>Keywords</strong></p><p>anterior cruciate ligament reconstruction; anterolateral ligament reconstruction; maturation; graft; signal-noise quotient; MRI</p><p><br></p><p><strong>What is known about the subjects?</strong></p><p>It is known that concomitant ALLR at the time of SBACLR results in a lower rate of graft rupture and fewer residual ACL deficiency signs when compared with isolated SBACLR. However, there is a controversy in the literature about the impact of concomitant ALLR on the healing of the ACLR graft.</p><p><br></p><p><strong>What this study adds to existing knowledge?</strong></p><p>The current study showed no association between concomitant ALLR and the ligamentization of the ACLR graft in terms of SNQ. However, better clinical outcomes were observed in the concomitant SBACLR-ALLR group. This suggests that the improved clinical results in concomitant SBACLR-ALLR are unlikely to be related to the potential influence of ALLR on the healing of the ACLR graft. Despite knowing that concomitant ALLR improves the clinical results of SBACLR, surgeons should continue to observe all recommended surgical practices when performing ACLR to ensure prompt healing and ligamentization of the graft.</p>