Effect of single-bundle and double-bundle anterior cruciate ligament reconstructions on pivot-shift kinematics in anterior cruciate ligament- and meniscus-deficient knees.
Academic Article
Overview
abstract
BACKGROUND: Recent laboratory and clinical studies report no difference between single-bundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstruction. HYPOTHESIS: Anatomical DB ACL reconstruction would restore knee kinematics in a complex injury model of ACL-meniscus injury closer to the intact state when compared with 2 common SB ACL reconstructions. STUDY DESIGN: Controlled laboratory study. METHODS: Five fresh-frozen cadaveric hip-to-toe lower extremity specimens were used for this study (10 knees). A surgical navigation system recorded the 3-dimensional motion path of a tracked point at the center of the medial and lateral compartments during a 68-N Lachman test and a mechanized pivot-shift test. Testing was performed on the intact knee, after ACL, medial meniscus, and lateral meniscus resection and after 3 ACL reconstructions: anatomical anteromedial SB, nonanatomical SB (posterolateral tibia to anteromedial femur), and anatomical DB. Same-sized hamstring grafts were used for all reconstructions. Repeated-measures analysis of variance with a post hoc Tukey multiple-comparison test was used to compare the anterior tibial translations of the 3 grafts during laxity testing. RESULTS: Regarding the Lachman test, there was no difference between the anatomical anteromedial SB and DB reconstructions. For the mechanized pivot shift, anatomical DB reconstruction restored anterior tibial translation to the intact state; however, significantly greater anterior tibial translation was detected after anatomical anteromedial SB and nonanatomical SB reconstruction, compared with the intact knee. In addition, there was no difference in medial compartment translations during the pivot shift between the intact and reconstructed states. CONCLUSION: Anatomical DB ACL reconstruction was able to restore intact knee kinematics during the pivot shift even in the severe injury model. CLINICAL RELEVANCE: Double-bundle ACL reconstruction procedures may be preferred in cases of high-grade instability or meniscus deficiency.
