Double bundle anterior cruciate ligament reconstruction: Failure rate and patients-reported outcomes at 4-11 years of follow up.

Background: Biomechanical studies have demonstrated that single bundle (SB) anterior cruciate ligament (ACL) reconstruction (SB-ACLr), which represents the gold standard for the management of ACL lesions, is not sufficient to completely restore the rotational stability and resistance to valgus stress of the knee.

Purpose: To evaluate the failure rate and patients reported outcomes at a long-term follow-up of double bundle anterior cruciate ligament reconstruction (DB-ACLr).

Study Design: Retrospective cohort study.

Materials And Methods: The database of arthroscopic DB-ACLr procedures performed from 2006 to 2015 at our Institution was retrospectively reviewed. Patients were screened for eligibility according to the following inclusion criteria: magnetic resonance imaging (MRI) evidence of anterior cruciate ligament (ACL) lesion, positive anterior drawer test and/or Lachman test; age ≤ 45 years at the time of surgery; DB-ACLr with autologous hamstrings, minimum follow up of 24 months. Patients were excluded if they presented associated lesions of the knee preoperatively or at the time of surgery, expect for meniscal lesions, or in case of inability to complete clinical questionnaires. Clinical outcomes were assessed at a mean follow up of 95.4 ± 21.9 months (range 51-129 months; median 98 months) using the Tegner-Lysholm score and the IKDC subjective score. Failures were defined as Tegner-Lysholm score ≤65 points, and were confirmed with MRI.

Results: 58 (81.7%) male and 13 (18.3%) female patients (mean age 29.7 ± 7.8 years) were included in the study. 2 (2.8%, 95% CI 0.3-9.8%) patients had a failure of DB-ACLr both occurred after a sports trauma. The IKDC subjective score was statically better in patients younger than 30 years. Tegner-Lysholm and IKDC subjective score were statistically better in professional athletes and in patients with isolated medial or lateral meniscus lesion instead of combined medial and lateral meniscus lesion.

Conclusion: DB-ACLr technique provides excellent clinical results at a long term follow-up. Low failure rate and high percentage of return to sports participation at the same pre-injury level was found in our cohort of patients.