Revision ACL reconstruction: influence of a lateral tenodesis.

PURPOSE: The aims of this article were to report the objective results of revision ACL reconstruction and to assess the influence of an associated lateral extra-articular tenodesis on knee stability and IKDC score. METHODS: This study focused on revision ACL reconstruction and was conducted over a 10-year period, from 1994 to 2003 with ten French orthopedic centers participating. The minimum follow-up required was 2 years. To be included, patients had to be evaluated at follow-up with the objective International Knee Documenting Committee (IKDC) scoring system. In 2006, 163 patients met the inclusion criteria. RESULTS: The objective IKDC knee score improved significantly after revision ACL reconstruction, with 72% IKDC A + B (26% A). When a lateral tenodesis was performed, 80% had a negative pivot shift, versus 63% without (P = 0.03), but there was no significant difference in the IKDC score. CONCLUSION: This study shows a significant improvement in the IKDC score after revision ACL reconstruction. The association of a lateral extra-articular tenodesis with the intra-articular graft increases knee stability after revision ACL reconstruction; however, this additional procedure does not significantly alter the IKDC score at follow-up. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Causes for failure of ACL reconstruction and influence of meniscectomies after revision.

The purpose of this multicenter retrospective study was to analyze the causes for failure of ACL reconstruction and the influence of meniscectomies after revision. This study was conducted over a 12-year period, from 1994 to 2005 with ten French orthopaedic centers participating. Assessment included the objective International Knee Documenting Committee (IKDC) 2000 scoring system evaluation. Two hundred and ninety-three patients were available for statistics. Untreated laxity, femoral and tibial tunnel malposition, impingement, failure of fixation were assessed, new traumatism and infection were recorded. Meniscus surgery was evaluated before, during or after primary ACL reconstruction, and then during or after revision ACL surgery. The main cause for failure of ACL reconstruction was femoral tunnel malposition in 36% of the cases. Forty-four percent of the patients with an anterior femoral tunnel as a cause for failure of the primary surgery were IKDC A after revision versus 24% if the cause of failure was not the femoral tunnel (P = 0.05). A 70% meniscectomy rate was found in revision ACL reconstruction. Comparison between patients with a total meniscectomy (n = 56) and patients with preserved menisci (n = 65) revealed a better functional result and knee stability in the non-meniscectomized group (P = 0.04). This study shows that the anterior femoral tunnel malposition is the main cause for failure in ACL reconstruction. This reason for failure should be considered as a predictive factor of good result of revision ACL reconstruction. Total meniscectomy jeopardizes functional result and knee stability at follow-up.

Using navigation to measure rotation kinematics during ACL reconstruction.

Rotational kinematics of the knee is not fully restored after single-bundle anterior cruciate ligament (ACL) reconstruction. Cadaveric experiments using knee testing machines have suggested anatomical reconstruction replacing the anteromedial and posterolateral bundles could restore knee kinematics more effectively than single-bundle reconstruction. However, practical tools to objectively assess knee rotational laxities clinically have not been available. We used an optically based computer-assisted navigation system to measure the tibiofemoral motion kinematics in four fresh whole cadavers. Standard clinical knee laxity tests (anterior drawer, Lachman, and pivot shift) were performed and the kinematics described in terms of tibial axial rotation and anteroposterior translation. Data were obtained for intact knees after excision of the ACL and sequential reconstruction of the anteromedial and posterolateral bundles. In the ACL-deficient knee, the mean maximum tibial rotation during the pivot shift test was 27 degrees and mean maximum translation 11 mm. Reconstruction of the anteromedial bundle reduced the rotational component to 18 degrees and translation to 7 mm. Reconstruction of the posterolateral bundle reduced rotation to 14 degrees . This pilot study suggests computer assisted navigation could provide a practical method to objectively measure the pivot shift and may be used clinically to demonstrate differences in the control of tibiofemoral rotation kinematics afforded by single and two-bundle ACL reconstructions.

Morphology of anterior cruciate ligament attachments for anatomic reconstruction: a cadaveric dissection and radiographic study.

PURPOSE: To define the positions of the attachments of the anteromedial (AM) and posterolateral (PL) bundles of the anterior cruciate ligament (ACL). METHODS: The shape and positions of the femoral and tibial attachments of the 2 bundles relative to bony landmarks were measured in 7 fresh-frozen, unpaired cadaveric knees by 6 independent observers. Metallic marker beads were then inserted into the defined anatomic points, and plain radiographs of the specimens were taken. We used the line described by Amis and Jakob on the tibia and the grid prepared by Bernard et al. for the femur to define AM and PL bundle attachment positions. RESULTS: In the cadaveric specimens, referencing the position of the AM bundle tibial attachment from the retro-eminence ridge (RER) resulted in the least interobserver error. On tibial radiographs, the distance between the posterior tibial cortex and the perpendicular projection of the center of the AM bundle attachment onto Amis and Jakob's line was 35.6 +/- 5.1 mm. The ratio of this distance to the length of Amis and Jakob's line (from the anterior cortex) was 36% +/- 3.8% (and 52% +/- 3.4% for the center of the PL bundle). On the femur, the center of the AM bundle was situated at 26.4% +/- 2.6%, and the center of the PL bundle at 32.3% +/- 3.9%, along the length of Blumensaat's line. CONCLUSIONS: The RER provides an easily identifiable and accurate reference point that can be used clinically. On a lateral radiograph, the positions of the tibial attachments can be referenced to Amis and Jakob's line. This method, different from Blumensaat's line, is independent of knee flexion. CLINICAL RELEVANCE: This study details anatomically and radiologically the positions of the attachments of the AM and PL bundles of the ACL. This could assist with accurate tunnel placement in reconstruction surgery and provide reference data for postoperative radiographic evaluation.

Double-stranded hamstring graft for anterior cruciate ligament reconstruction.

Current techniques for anterior cruciate ligament (ACL) reconstruction do not completely reproduce the anatomy and function of the ACL. They address only the anteromedial bundle and do not fully restore ACL function throughout the range of motion. Current grafts control anterior tibial subluxation near extension, but are less efficacious in providing rotatory stability. Recently, several authors have suggested reconstructing not just the anteromedial bundle but also the posterolateral bundle. This technical note describes a double-bundle ACL reconstruction using hamstring tendons routed through 2 tibial and 2 femoral independent tunnels.