Preservation of the MMPH and Status of the Notch Configurations Are Important Factors for Successful Revision ACL Reconstruction.

Objective: The aim of this study was to identify the differences in anatomical factors between the patients who underwent revision and primary anterior cruciate ligament reconstructions (ACLR) and compare the outcomes between the 2 surgeries.

Design: Retrospective cohort study.

Setting: Single institution tertiary academic center between 2014 and 2020.

Patients: A total of 84 matched patients who underwent revision (group I) or primary ACLR (group II).

Interventions: Radiological evaluations were performed using side-to-side differences (SS-D), femorotibial angle, and posterior tibial slope. The medial meniscus posterior horn status as width (MMPHW), medial tibial plateau width (MTPW), notch configurations, tunnel positions, and sagittal graft angle were measured using 3D-CT and magnetic resonance imaging (MRI).

Main Outcome Measures: Graft signals were assessed using MRI. The clinical outcomes were assessed.

Results: Group I showed larger SS-D and higher mean Howell grade of anterior cruciate ligament (ACL) graft than group II ( P = 0.002 and P = 0.004, respectively). Multivariate regression analyses showed that the decreased MMPHW/MTPW ratio ( P = 0.010) and notch width index ( P < 0.007) were significantly independent factors associated with the higher Howell grade of ACL grafts. The decreased MMPHW/MTPW ratio ( P < 0.001) was a significantly independent factor associated with larger SS-D. In the subgroup analysis, all patients in the notchplasty group showed wider notches postoperatively ( P < 0.001).

Conclusions: Revision ACLRs resulted in worse ACL signal intensity and stability outcome. The results of this study suggest that it may be important to preserve the MMPHW as much as possible and check notch configurations, especially during a revision ACLR.