Comparison of Outcomes Between a Fixed-Loop Cortical Suspensory Device and Metal Interference Screw for Femoral Fixation of Bone–Patellar Tendon–Bone Grafts in Anterior Cruciate Ligament Reconstruction: A Scandinavian Registry Study

Abstract

Background:

Use of a cortical suspensory device (CSD) is an alternative fixation method for bone–patellar tendon–bone (BPTB) in the femur. To the authors’ knowledge, no study has compared revision outcomes and patient-reported outcomes (PROs) with the traditional interference screw (IS) fixation.

Purpose:

To compare the survival rate of grafts fixated on the femoral side with either a fixed-loop CSD or IS for primary anterior cruciate ligament reconstructions (ACLRs) with BPTB autograft 2 and 5 years after index surgery, as well as to compare PROs between the same 2 treatment groups based on data from 3 National Knee Ligament Registers (NKLRs) in Scandinavia.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

The study included patients registered in the NKLRs of Norway, Denmark, and Sweden who underwent primary ACLR from 2005 to 2021. Patients undergoing additional surgery for concomitant injuries to the posterior cruciate ligament, lateral collateral ligament, or medial collateral ligament and patients with major cartilage lesions were excluded. Cox regression models with and without adjustment for possible confounding from age, sex, meniscal and chondral injury, tibial fixation, surgical time, time from injury to surgery, injury mechanism, and country were used to calculate hazard ratios (HRs) and 95% confidence intervals. The possible effects of femoral fixation on 1-year postoperative KOOS QoL and on change from preoperative to 1-year postoperative KOOS QoL were analyzed using multiple linear regression with adjustment from possible confounding from the same variables. P values <.05 were considered significant.

Results:

A total of 13,955 primary ACLRs met the inclusion criteria during the study period; 1852 patients (13%) had a femoral CSD fixation and 12,103 patients (87%) a femoral IS fixation. No significant difference was observed in overall risk of revision between CSD and IS (HR, 1.10; 95% CI, 0.83 to 1.47; P = .5), and differences in cumulative survival at 2 years (CSD: 98.3% vs IS: 98.6%) and 5 years (CSD: 96.3% vs IS: 96.4%) were not statistically significant. No difference was found for mean KOOS QoL delta (1 year minus baseline) when adjusting for possible confounders (mean difference, –1.60; 95% CI, –3.83 to 0.63; P = .16).

Conclusion:

Data from the Scandinavian NKLRs showed no difference in the risk of revision and no difference in the KOOS QoL for fixed-loop CSD fixation compared with IS fixation on the femoral side with BPTB grafts in primary ACL reconstruction.