A prospective randomized study comparing double- and
single-bundle techniques for anterior cruciate ligament reconstruction

Ahlden M, Sernery N,
Karlsson J, and Kartus J. Am J Sports Med. 2013; [Epub Ahead of Print}

Take Home Message: Patients receiving single-bundle or
double-bundle techniques for ACL reconstruction have similar favorable
patient-reported and objective measures at 2 years post-surgery.

Despite development
of both the single-bundle and double-bundle technique for reconstructions of
anterior cruciate ligament (ACL) ruptures, a definitive gold-standard is still
debated. Therefore, we need more clinical trials to identify which technique is
most beneficial in terms of post-surgical knee stability. Therefore, Alden and
colleagues completed a prospective, randomized controlled trial of 98 patients
from 2 hospitals in western Sweden to investigate which surgical method had
better clinical outcomes at 2 years post-surgery. The authors used the pivot-shift test to
assess their primary outcome measure, which was the degree of rotational
laxity. The secondary outcome measures were functional tests (1-legged hop test, square
hop test, Lachman test
and KT-1000 arthrometer)
and patient-reported outcome measurements (Lysholm knee scoring scale,
KOOS, and Tegner activity scale). The authors included patients who sustained a unilateral
ACL injury, were 18 years of older, and failed nonsurgical treatment. Following
inclusion, patients were randomized into either a single-bundle technique group
(SBG) or double-bundle technique group (DBG). All patients, regardless of
group, underwent a hamstring tendon graft and followed the same rehabilitation
guidelines. One physical therapist, who was blinded to the type of surgical
technique the patient received, assessed the patients at both the preoperative
and 2 year follow-up examination. Overall, 38 of 50 (76%) patients in the SBG
and 35 of 53 (66%) patients in the DBG had meniscal injuries either at the time
of surgery or during the follow-up period. At the 2 year follow-up, the 2
groups had similar patient-reported outcomes (KOOS, Tegner activity level,
Lysholm score),  anterior knee laxity as
measured by the KT-1000 arthrometer or Lachman test, and rotational laxity as
assessed with the pivot-shift test (negative pivot-shift test: 67% and 79% of
patients in the SBG and DBG, respectively).

Overall, the authors
demonstrate that neither graft was more beneficial in terms of mitigating
rotational laxity than the other. This is relevant since ligament laxity
increases the risk of episodes of “giving away”. Therefore, clinicians must
identify the best surgical technique to eliminate episodes of “giving away” and
increase the patient’s ability to return to physical activity. While the
authors found that neither group performed significantly better than the other,
there were limitations. Firstly, patients had varying degrees of meniscal
injury, which may lead to less stability in the joint. Secondly, the outcome
measures (e.g., pivot-shift test and Lachman test) were fairly subjective.
Future research on this topic should look to magnetic resonance imaging to
better assess joint laxity. Finally, the indication for surgery in this study
was failing nonsurgical treatment but there was no indication regarding how
long after the injury the surgery was delayed. If the patient eventually failed
nonsurgical treatment, then at least some patients subjected their joint to
increase strain on the surrounding structures in episode of “giving away.”
Ultimately this study presents data to support the idea that regardless of
graft technique all patients, age 18 or older with unilateral ACL tears should
respond well with regards to laxity following ACL reconstruction surgery.

Questions for Discussion: In your current setting do you
often counsel your patients on choosing surgical options such as graft type, bundle
type, etc.? Do you believe this data will have an impact on our ultimate goal
of identifying a true gold-standard ACL reconstruction surgical method?

Written by: Kyle Harris
Reviewed by:  Jeffrey Driban

Related Posts:

Ahldén M, Sernert N, Karlsson J, & Kartus J (2013). A Prospective Randomized Study Comparing Double- and Single-Bundle Techniques for Anterior Cruciate Ligament Reconstruction. The American Journal of Sports Medicine PMID: 23921339