Risk of Revision for Various Hamstring Fixation Methods after ACLR

Abstract

Objectives:Risk factors for anterior cruciate ligament reconstruction (ACLR) revision have included graft type, as well as fixation methods. Newer fixation techniques and devices for hamstring (HS) autograft have been introduced over the years. The purpose of this study was to compare the risk of aseptic revision after HS autograft ACLR between various femoral and tibial fixation methods/devices.Methods:Patients who underwent primary ACLR using a HS autograft from 2007-2014 were identified through a community-based registry for this retrospective cohort study. Bilateral, double bundle, and multiligament ACLRs were excluded. Patients were categorized (crosspin, interference, suspensory, or combination [more than one fixation]) based on the type of fixation utilized for the femur and tibia. Femoral/tibial fixation groupings with more than 500 patients were evaluated as a risk factor for aseptic revision, with adjustment for age, sex, body mass index, and race/ethnicity, using a multivariable Cox proportional-hazards regression model.Results:6,716 primary ACLR patients were included, of whom 2,894 (38.8%) were younger than 22 years old, 4,111 (61.2%) were male, 2,956 (44.0%) had a BMI < 25 kg/m2, and 3,163 (47.1%) were caucasian. Five femoral/tibial groupings had more than 500 patients: suspensory/interference (n=2,176, 32.4%), suspensory/combination (n=1,940, 28.9%), interference/combination (n=1,025, 15.3%), interference/interference (n=845, 12.6%), and crosspin/combination (n=730, 10.9%). The cumulative failure probability at 5 years was highest for the suspensory/interference group (9.0%, 95% CI 7.2-11.2), followed by suspensory/combination (6.7%, 95% CI 5.4-8.4), interference/interference (5.1%, 95% CI 3.7-7.2), interference/combination (4.3%, 95% CI 2.9-6.3), and crosspin/combination (3.1%, 95% CI 2.0-4.9). After adjusting for the other covariates, the hazard ratio for aseptic revision was 2.9 (95% CI 1.9-4.7) for the suspensory/interference group, 2.7 (95% CI 1.7-4.5) for the suspensory/combination group, 1.6 (95% CI 0.9-3.0) for the interference/combination group, and 2.1 (95% CI 1.2-3.7) for the interference/interference group when compared to the crosspin/combination group.Conclusion:ACLR using HS autograft appears to have the highest risk of aseptic revision when suspensory fixation is used on the femoral side and is coupled with either an interference screw or combination fixation on the tibial side. Understanding the device-related risk of aseptic revision after HS autograft ACLR will help guide surgeons regarding which devices may negatively influence surgical outcomes.