Prospective Randomized Comparison of Knee Stability and Joint Degeneration for Double- and Single-Bundle ACL Reconstruction
Sun R, Chen B, Wang F, Wang X, & Chen J. Knee Surg Sports Traumatol Arthrosc. 2014 Published Online First March 22, 2014: doi: 10.1007/s00167-014-2934-4
Take Home Message: Double-bundle ACL reconstruction with allograft or autograft may be superior to single-bundle techniques with allograft at enhancing knee stability but all three procedures have comparable patient-reported outcomes.
Despite anterior cruciate ligament (ACL) reconstructions being a common surgical procedure it remains unclear which surgical technique or graft selection is best for ACL reconstruction. Therefore, the purpose of this randomized trial was to investigate the stability, functional outcomes, clinical evaluation, and radiologic outcomes among participants who received one of three ACL reconstructions: 1) single-bundle technique with an allograft (142 participants), 2) double-bundle technique with an allograft (128 participants), and 3) double-bundle technique with a hamstring autograft (154 participants). The authors evaluated the participants at 3, 12, and 36 months after surgery. Both double-bundle groups had better anterior knee stability than the single-bundle group at 12 and 36 months after surgery as measured by KT-1000. Similarly, more individuals in both double-bundle groups had negative pivot-shift tests at all follow-up time points. Despite differences in laxity, all three groups had similar self-reported knee symptoms and function as measured by IKDC 2000 and Lysholm scores.
This study supports previous research that showed that the double-bundle technique achieves better stability (anterior and rotational) than the single bundle. This may be contributed to a more anatomic replication of the original ACL. However, a more stable knee does not appear to cause clinically detectable differences in symptoms or function among participants. This also raises the question about whether the improved stability would ward off osteoarthritis. After all, many people function without an ACL and have comparable rates of osteoarthritis as those with an ACL reconstruction. The double-bundle technique may need to be investigated further to determine if it offers better long-term outcomes since there appears to be minimal differences in the relatively short-term follow up. Furthermore, among participants who received the double-bundle technique, there were no differences between the participants who received the autograft or allograft. There is limited research with double-bundle allograft techniques, and this study seems to support that it is as effective as the more traditional double bundle with autograft selection. This provides a nice alternative for another graft option in a patient population that may be susceptible to complications from the hamstring autograft harvesting as there were no differences in clinical outcomes (e.g., Lysholm and IKDC 2000). Interestingly, these results indicate that the double-bundle techniques may be superior to a single bundle technique with allograft at enhancing knee stability but all three procedures may lead to similar patient-reported outcomes.
Questions for Discussion: Do you think that double-bundle technique will be more frequently chosen for ACL Reconstruction? Have you worked with patients that have had a double-bundle ACL reconstruction done – and if so, are there any clinical difference that you notice in comparison to a single bundle technique?
Written by: Nicole Cattano
Reviewed by: Jeffrey Driban