Femoral Aperture Fixation Improves Anterior Cruciate Ligament Graft Function When Added to Cortical Suspensory Fixation

Abstract

Background:Recommendations for bone tunnel placement during anterior cruciate ligament (ACL) reconstruction have become more precise. However, these recommendations differ neither with the choice of graft nor with the method of fixation used. The influence of the method of femoral fixation used on the biomechanical function of a soft tissue ACL graft remains unknown.Hypothesis:Our null hypothesis was that adding femoral aperture fixation to femoral cortical fixation, using the same bone tunnels, will not alter the control of anterior translation (AT) and internal rotation (IR) during ACL reconstruction using a hamstring graft.Study Design:Controlled laboratory study.Methods:A total of 22 patients with an acute isolated ACL rupture underwent reconstruction using a single-bundle autologous hamstring graft. Computer navigation was used intraoperatively to plot the AT and IR during the pivot-shift test before reconstruction, after ACL reconstruction using cortical suspensory fixation, and after the addition of femoral aperture fixation. Statistical analysis (analysis of variance) was used to compare the AT and IR during the pivot shift at each stage in the procedure.Results:Before ACL reconstruction, the mean (±SD) AT was 14.2 ± 7.3 mm and mean IR was 17.2° ± 5.5°. After reconstruction using femoral cortical suspension, these figures were significantly reduced to 6.2 ± 3.5 mm and 12.5° ± 3.20°, respectively (P < .001). The addition of the aperture fixation was associated with a further significant reduction to 4.6 ± 3.2 mm and 10.4° ± 2.7°, respectively (P < .001).Conclusion:The addition of femoral aperture fixation to suspensory fixation results in a significant reduction in both the AT and IR that occurs during the pivot-shift assessment immediately after ACL reconstruction using autologous hamstring graft.Clinical Relevance:The most precise positioning of bone tunnels during soft tissue ACL reconstruction needs to take into consideration the type of fixation being used.

Passive anterior tibia translation in anterior cruciate ligament-injured, anterior cruciate ligament-reconstructed and healthy knees: a systematic review

“…Two studies reported significant differences between graft fixation methods [27, 28]. However, others did not report any differences in graft fixation methods [21, 29–34].…”

The Augmentation of Revision Anterior Cruciate Ligament Reconstruction With Modified Iliotibial Band Tenodesis to Correct the Pivot Shift: A Computer Navigation Study

“…52 Other research has shown that by using a single-bundle reconstruction technique with optimal tunnel placement and aperture fixation, it is possible to control both the anterior translation (AT) and internal rotation (IR) that occur during the pivot shift after an isolated ACL rupture. 36,37 It has been suggested that the persistent rotational instability seen after ACL reconstruction in some patients is caused by peripheral injuries, 1,30,34,39 that is, injuries to anterolateral extra-articular tissue. In these cases, even optimal ACL reconstruction procedures may fail to control rotational laxity.…”

“…52 Other research has shown that by using a single-bundle reconstruction technique with optimal tunnel placement and aperture fixation, it is possible to control both the anterior translation (AT) and internal rotation (IR) that occur during the pivot shift after an isolated ACL rupture. 36,37…”

Editorial Commentary: Rehabilitation and Return-to-Sports Readiness, the “Black Box” of Anterior Cruciate Ligament Reconstruction Patient Recovery

“…Time 0 studies suggest that soft tissue grafts with extracortical suspensory fixation may be prone to stretching effects, expressed as tunnel slippage or graft elongation, rather than outright failure. [1][2][3] The rehabilitation team needs to weigh the benefits of therapeutic exercise movements and loading tasks versus the risks of soft tissue graft stretching, particularly during early recovery. With this understanding, they are challenged to ensure that the patient regains sufficient neuromuscular knee control before undertaking therapeutic exercise or activity loading events that might adversely stretch the graft.…”

“…Time 0 studies have suggested that anatomic soft tissue graft placement with tunnel aperture fixation may more effectively restore this important characteristic than other fixation methods. [1][2][3] Although contemporary ACL reconstruction simulates precision carpentry of the highest order, ACL graft neurosensory function is not restored even in a remotely similar way to the native healthy ACL. 15,16 Therefore, additional recovery time in conjunction with a more gradual criteria-or guideline-based rehabilitation and return-to-sports progression would be advantageous to more complete neuromuscular control and dynamic knee stability restoration.…”